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Enhander
April 30, 2017, 17:28
Guys,
I am in need of some insight/assistance. I recently finished my M16A2 build and I am having some minor issues with it. First off, here she is:

http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/m16a2-2_zpsrppmhjnb.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/m16a2-2_zpsrppmhjnb.jpg.html)

Easily one of my favorites of my collection. Im having some function issues with it though. The malfunction that happens frequently is the bolt fails to lock back on the final round. I would say 80% of the time it doesn't. The second issue is that sometimes I'll get a failure to feed into the chamber. Today I shot about 50 rounds and had 3 Failure to Feeds between the three magazines I brought.

I used 3 magazines today. Two Magpul (a Gen 2 30 rounder and a Gen 3 10 rounder) and a standard GI mag. All mags had the same issues and are known to function fine on my other two ARs.

My first thought was the buffer spring. The stock I bought was the UTG A2 stock that included the buffer, buffer spring and tube. They seemed to be of good quality, but I have got some UTG stuff in the past that questionable.

My second thought was the upper/barrel combo. The barrel I purchased is a Delton 20 inch 1x9 Government profile barrel with M4 Feed ramps. The A2 upper that I purchased is a DPMS A2 upper that is not cut for M4 Feed ramps.

If that is the issue, is there a way to remedy it?

My third and final thought pointed to there being something possibly wrong with my gas tube...but I figure if that were the issue then I would be experiencing a lot more issues that I am now.

Accuracy is not an issue...as seen below:
http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/IMG_6284_zpshdjanwry.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/IMG_6284_zpshdjanwry.jpg.html)


Any help is greatly appreciated.
Thanks in advanced! :bow:

meltblown
April 30, 2017, 17:58
Gas port lining up with the FSB?

Enhander
April 30, 2017, 18:04
I just looked at it and everything appears to line up correctly.

burtman
April 30, 2017, 18:16
From a Opticplanets review of said utg stock assembly 6 months ago


Problem encountered.

by Jon, from PA, United States Written on December 14, 2016

I purchased this stock because I wanted an A2 rifle stock to complete my rifle's look. After assembly, which was flawless, when the rifle was tested it had problems with FTF traced to failure to load, regardless of magazine used. Because everything checked out, I decided to compare the recoil spring from the A2 stock with another rifle's spring, and found my spring to be 2" shorter than the sample. Replacing the Leapers spring with the sample cleared up my malfunctions, so I suspect the company shipped this rifle stock with a carbine length spring. I had to find and purchase the correct length spring to get this rifle up and running. The stock itself is strong and dead black in color, which is fine, but the supplied spring caused me malfunctions.

Pros:
None
Cons:
Weak spring.
Best Used for:
A2 type build.
A2 build
Would recommend: No
Was it helpful to you? Yes / No
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Comments

Enhander
April 30, 2017, 18:44
Son of gun... Thats gotta be it then. Any suggestions on a good spring?

I will pick up this one unless you all know of a better one.
http://www.primaryarms.com/anderson-manufacturing-ar-15-rifle-length-buffer-spring-am-20-rif

Ive had good luck with Anderson parts, but if there is a better one, I'll certainly get it. :bow:

burtman
April 30, 2017, 19:08
I also have had good experiences with Anderson however something from Del-Ton or Fulton armory and M&A parts would likely suit your needs as well

Having a 20" Del-Ton barrel on one of my builds I can say I am very happy with it and yours seems to group very nicely

sharkey
May 01, 2017, 01:46
Here is a pic of the difference between the rifle and carbine buffer springs. Measure the length and count the loops.
http://s860.photobucket.com/user/jepp2/media/BufferSpring.jpg.html

Also, check your disconnector, make sure its not rubbing on the hammer hook as the action is cycling to the rear. A new, incorrectly timed, disco will sometimes bang off the hammer hook causing cycling issues. To check, shotgun open the receiver by pushing the rear take down pin through. Using your thumb to cock the hammer manually; watch the disco hook where it meets the hammer hook. Right as the two meet. Finger off the trigger. The disco should drop back as the two meet each other. If the hammer hook rides up on the disco hook before the reset, the disco will need to either be replaced or reprofiled.

TerryN
May 02, 2017, 07:53
Sounds like a gas iisue to me - as in, not enough gas to reliably cycle the rifle. Have you tried other ammo in the rifle? Have you tried this ammo in other rifles? If this rifle malfunctions consistently with other ammo, I would first check the bolt carrier key.

Check your bolt carrier key screws; tight, properly staked?

If this ammo runs well in other rifles, I would also be inclined to suspect the bolt carrier key.

jdmcomp
May 02, 2017, 08:35
I do remember from one of my early builds the instructions (yes, they actually did give you instructions with the kits then) that until you fired enough rounds to cause carbon buildup between the FSB and the Barrel you might get some blowback from the FSB (and I did) and function might be a problem. Normally cleared up after a number of rounds fired, but I do not remember that number. Check the barrel around the FSB to see if there are marks from gas leakage.

V guy
May 02, 2017, 10:05
Sounds like you built an Original type gun.!!

The early M16A1 manual is full of pics about how those early guns malfunctioned, and the types of jams incurred.

Damn, an original build is still possible!!!!:bow::bow:
It may be worth more.

So, I only have to put a carbine spring in my early SP1............ to duplicate an early gun, completely.

oleblu72
May 02, 2017, 10:28
Looks like I better start looking for a rifle length spring & buffer. I built a 6.8 with a 22'' barrel with a rifle length gas port. It has a Palmetto lower and I think it has a carbine length spring & buffer.

Mark

M90A1
May 02, 2017, 16:27
Looks like I better start looking for a rifle length spring & buffer. I built a 6.8 with a 22'' barrel with a rifle length gas port. It has a Palmetto lower and I think it has a carbine length spring & buffer.

Mark

Which buffer tube/stock are you running? If you have a carbine buffer/spring in a rifle buffer tube, sooner or later you're going to have a very large problem.

hueyville
May 02, 2017, 18:31
Tubbs Flatwire and a few others are interchangeable between carbine and rifle. Like the Tubbs as are super reliable, interchangeable and seen them fix a few problem rifles that had gremlins causing cycling issues. Best part is eliminates a significant amount of the Spprrooinggg issue common with AR's. So many bargain kits come with springs of completely unknown (chinese lowest bid) origin it's a wonder spring issues are not more common.

Enhander
May 02, 2017, 19:35
Sounds like a gas iisue to me - as in, not enough gas to reliably cycle the rifle. Have you tried other ammo in the rifle? Have you tried this ammo in other rifles? If this rifle malfunctions consistently with other ammo, I would first check the bolt carrier key.

Check your bolt carrier key screws; tight, properly staked?

If this ammo runs well in other rifles, I would also be inclined to suspect the bolt carrier key.

Haven't got a chance to shoot any other ammo in the rifle. The ammo in my other rifles shoots without issue.

Enhander
May 02, 2017, 19:37
I do remember from one of my early builds the instructions (yes, they actually did give you instructions with the kits then) that until you fired enough rounds to cause carbon buildup between the FSB and the Barrel you might get some blowback from the FSB (and I did) and function might be a problem. Normally cleared up after a number of rounds fired, but I do not remember that number. Check the barrel around the FSB to see if there are marks from gas leakage.


So far Ive got about 70 rounds through it. The first time I shot it, the problems went away after the first mag, so I thought everything was ok. :facepalm:

Enhander
May 02, 2017, 20:28
Ok, so I measured the buffer springs. Turns out its in the correct length for a rifle spring. Im still going to try one of the new springs just to see if the included spring of UTG is just crappy quality.

I checked the FSB to see if there was any gas discharge and it was clean.

The staking on the bolt carrier key looks fine and it is solid. See below.

The trigger seems to operate correctly, I may install a known good trigger in it to see if that would make a difference. If it turns out being the trigger/disconnector/hammer timing..I'll just buy an ALG trigger and be done with it. I run those in all my rifles and they have never let me down.

http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/451B3CBE-9C4C-4386-97DF-7376D4CA66A4_zpsbxklacdh.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/451B3CBE-9C4C-4386-97DF-7376D4CA66A4_zpsbxklacdh.jpg.html)

http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/045BFAD4-AA98-419F-8ED6-3B4555945D3C_zpsgpwbngv8.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/045BFAD4-AA98-419F-8ED6-3B4555945D3C_zpsgpwbngv8.jpg.html)

lysanderxiii
May 02, 2017, 21:51
Embrace the "sproing"

hueyville
May 03, 2017, 04:59
Embrace the "sproing"

Tame the "Sproing". Flatwire spring, heavy buffer, proper gas and the tell-tale sound signature of an AR running goes away. Better suppressor twist on, the more you notice how much noise is generated by the "sproing" and want to calm it down as part of making the rifle quiet as possible.

For OP,
Have you tried more than the three magazines? Suggest go buy a couple new name brand metal mags with chrome silicon springs and anti-tilt followers, preferably with one of the self lubricating internal finishes. I suspect a magazine issue. Have thrown more than one in the rebuild pile on the same day. Go buy some magazine rebuild kits and stop using Pmags to test a rifle. They are for proven rifles IMHO.

Enhander
May 03, 2017, 06:46
Tame the "Sproing". Flatwire spring, heavy buffer, proper gas and the tell-tale sound signature of an AR running goes away. Better suppressor twist on, the more you notice how much noise is generated by the "sproing" and want to calm it down as part of making the rifle quiet as possible.

For OP,
Have you tried more than the three magazines? Suggest go buy a couple new name brand metal mags with chrome silicon springs and anti-tilt followers, preferably with one of the self lubricating internal finishes. I suspect a magazine issue. Have thrown more than one in the rebuild pile on the same day. Go buy some magazine rebuild kits and stop using Pmags to test a rifle. They are for proven rifles IMHO.

I havent shopped much for metal mags. Any good suggestions? I know Brownells sells a bunch of different metal mags that they brand. Would those work or is there something better?

hueyville
May 03, 2017, 07:32
Palmetto has D&H aluminum mags with anti-tilt followers on sale for $7.99 right now with free shipping on 10 or more. Put a dozen in my cart right after my last post here. Buy at least enough for the free shipping.

hueyville
May 03, 2017, 07:46
J&G Sales has MSC stainless in 5.56 and 6.8 for 10.95 each if buy ten. Just dropped a dozen of each of those in cart and bought. My favorite magazine. Stainless steel, microslick finish on interior, orange anti-tilt follower, chrome silicone springs. My go to magazine in every AR other than Lancer L5's. Wow, 36 mags today and still shopping.

Enhander
May 03, 2017, 08:02
Good deal. I'll have to pick some up asap.

Zeusizme
May 03, 2017, 08:14
UTG products are mostly trash. If you're going to spend money always spend it wisely by shelling out a few extra for hardware of known good quality.

P.S. you'll spend less money in the end by buying better quality products first.

hueyville
May 03, 2017, 08:33
UTG products are mostly trash. If you're going to spend money always spend it wisely by shelling out a few extra for hardware of known good quality.

P.S. you'll spend less money in the end by buying better quality products first.

I was under impression that UTG only makes airsoft products but some people sell for gun market with misleading advertising. Correct me if wrong but will agree, UTG is on my list of don't buy and if comes in junk box deal then trade off or give away.

Enhander
May 03, 2017, 08:51
Live and learn I guess...I won't be buying anymore of their products.

Enhander
May 03, 2017, 09:13
Would it be safe to assume that the buffer that came in the UTG kit is garbage also?

Enhander
May 03, 2017, 09:20
J&G Sales has MSC stainless in 5.56 and 6.8 for 10.95 each if buy ten. Just dropped a dozen of each of those in cart and bought. My favorite magazine. Stainless steel, microslick finish on interior, orange anti-tilt follower, chrome silicone springs. My go to magazine in every AR other than Lancer L5's. Wow, 36 mags today and still shopping.


Did you mean ASC?

http://www.jgsales.com/asc-ar-15-223-5.56mm-20rd-magazine,-black-stainless,-new.-p-6814.html

hueyville
May 03, 2017, 10:35
Yes ASC. Typing too fast and spell check doesn't help with initials. But one of three of my favorite magazines. Reasonably priced, every feature you need and never had one fail. Used to have a choice in color of followers, may still but only saw orange on J&G this morning. Bought a bunch before then realized like the orange followers for civilian/range/plinking. If in combat might prefer the grey followers might be less noticed if still partially sticking out of drop bag but doubt would be an issue then. If in a firefight at close enough range for opposing force to see the followers of empty mags in drop bag world has gone to crap and have bigger issues.

One the failure to lock bolt on last round, have rifles that lock back 100% on any magazine except Pmags. Most of my rifles have Pmags they don't like to lock on last round. Of course using strong buffer springs and heavy buffers with well adjusted gas to slow bolt speed. If rifle is over gassed bolt will run so fast will be closing before next round comes to top of feed lips or follower pops up to stop it. Why use curly gas tubes on carbine length rifles, adjustible gas and heavy buffers. Mid or rifle length when can and find that fine line where 40 grain varmint bullets or 77 grain long range bullets and any in between cycle with slowest rate of fire can get. Calms entire rifle down but have to open gas just a bit when find its edge to guarantee reliability so the extra gas is there if shoot some 90 grain or 35 grain ammo. That's a wide range and requires a little headroom unless want to monkey with buffers or gas settings on the fly.

Been test running some MGI adjustible gas tubes as easy peasy to stick Allen wrench in top if no full length pic rail. Are great with stock milspec handguards though read if twist on a lot can break them. Will know before long though mostly using on rifles that once gas is set, leave alone. Have one on a range rifle and purposely adjusting often to see for myself if it will break. They are expensive and out of stock all the time but have three carbine and one mid playing with. Of course home brewing a front sight tower to adjustible gas costs 15 cents for a grub screw and some time to drill and tap. Why so many of my builds have F Mount front sight towers as get for free to $5 as take offs and can drill tap, add screw then don't have to buy an expensive BUIS flip up front sight even though more tacticool.

burtman
May 03, 2017, 12:23
I am assuming that this is your stock assembly - and the spring is coated in a semi gloss black layer of ?? I've been running some lower end utg carbine stocks lately and the springs are the only thing I replaced. I couldn't find anything wrong with them just didn't care for them

85103

Enhander
May 03, 2017, 12:49
I am assuming that this is your stock assembly - and the spring is coated in a semi gloss black layer of ?? I've been running some lower end utg carbine stocks lately and the springs are the only thing I replaced. I couldn't find anything wrong with them just didn't care for them

85103



Yep, thats the one. Same black, rubbery coating type spring. I have a new spring coming in the mail...Hopefully I can test it this weekend. Im going to bring my main AR with me...I know it functions flawlessly. I'll have it there to test parts...etc... I'll also be bringing a variety of mags and ammo.

jhend170
May 03, 2017, 12:51
Being too lazy to look if it was asked...

How is ejection of spent brass? Is it launched with authority or does it dribble out? Dribbling tends toward gas issues, if it's launched but short strokes it can be something affecting the BCG.

Have you checked the gas rings? Bad rings or improperly machined carrier can cause a leak there. Buddy had one that ate rings, tuned out there was a bur that couldn't be seen deep in the bolt hole.

If the system is cycling too fast it may not be allowing the mag spring to lift the next round into place before the bolt closes. A heavier buffer can help with slowing cyclic times, although I consider this unlikely with a rifle-length gas system. If you have a larger than necessary gas port this is still possible though as it's over-gassed.

As discussed, a heavier-than-necessary spring can cause this short/fast cyclic issue as well. Get a name-brand that matters.

Didn't see it anywhere, but with your rifle spring you have a rifle buffer, correct?

Any evidence of leakage from your gas tube at either end?

Have you checked the gas tube for any blockages (pulled it and blown through it)?

When asked about the gas block you answered "it looks properly aligned." Did you remove it to verify position within the GB and on the barrel? How it looks mounted doesn't mean the holes are properly aligned and only looking will tell you. There will be an obvious ring in the GB where the port has been sitting.

Have you looked inside the buffer tube to ensure there is no dragging or anything at the back that would cause it to short cycle?

Enhander
May 03, 2017, 13:27
Being too lazy to look if it was asked...

How is ejection of spent brass? Is it launched with authority or does it dribble out? Dribbling tends toward gas issues, if it's launched but short strokes it can be something affecting the BCG.

Have you checked the gas rings? Bad rings or improperly machined carrier can cause a leak there. Buddy had one that ate rings, tuned out there was a bur that couldn't be seen deep in the bolt hole.

If the system is cycling too fast it may not be allowing the mag spring to lift the next round into place before the bolt closes. A heavier buffer can help with slowing cyclic times, although I consider this unlikely with a rifle-length gas system. If you have a larger than necessary gas port this is still possible though as it's over-gassed.

As discussed, a heavier-than-necessary spring can cause this short/fast cyclic issue as well. Get a name-brand that matters.

Didn't see it anywhere, but with your rifle spring you have a rifle buffer, correct?

Any evidence of leakage from your gas tube at either end?

Have you checked the gas tube for any blockages (pulled it and blown through it)?

When asked about the gas block you answered "it looks properly aligned." Did you remove it to verify position within the GB and on the barrel? How it looks mounted doesn't mean the holes are properly aligned and only looking will tell you. There will be an obvious ring in the GB where the port has been sitting.

Have you looked inside the buffer tube to ensure there is no dragging or anything at the back that would cause it to short cycle?


Ok, to answer your questions:
1) Brass ejection is pretty good. It launches them pretty far.
2) Haven't checked the rings yet....will do so asap
3) Correct, Im running a rifle buffer
4) No visible signs of leakage. Haven't check the tube for blockages yet...I'll do that as well
5) I'll check to make sure the holes are properly aligned on the Gas block as well
6) I'll check the inside of the buffer tube for obstructions.

Enhander
May 03, 2017, 14:28
You know, now that I think of it...the first time I tested the rifle I was using a different BCG. The current BCG that is installed was still in the mail and I really wanted to test the rifle out.

The first test of the rifle I had very minor problems. By the end of the testing the rifle was operating fine. Bolt locked back as normal, no FTFs.

Perhaps I'll snap a few pics of the bolt itself and let you all take a look.

Enhander
May 03, 2017, 15:31
You know, now that I think of it...the first time I tested the rifle I was using a different BCG. The current BCG that is installed was still in the mail and I really wanted to test the rifle out.

The first test of the rifle I had very minor problems. By the end of the testing the rifle was operating fine. Bolt locked back as normal, no FTFs.

Perhaps I'll snap a few pics of the bolt itself and let you all take a look.

I just watched the video I uploaded to my YouTube channel and it appears that I had 1 FTF and 2 Failure to Lock open on last round fired. However, I can say that the bolt locked open more frequently on this first test. I didn't film the last 20 rounds I fired before I left the range. I fired 10 rounds, reloaded the mag and fired another 10. Both times the Bolt locked back.

hueyville
May 04, 2017, 08:30
Am almost caught up with onslaught of work and be back to normal work load by mid week following outpatient tomorrow. This means builds are about to happen with carbines in 5.56, 6.8, a pair of A2's in 5.56 Wylde and 22 Nosler. Will do everything from squaring the uppers, chasing upper receiver threads, torquing barrel nut, proper alignment of a F front sight tower, converting front sight tower to adjustible gas, low profile gas blocks, installing delta ring assembly for OEM handguards, free float forearms, muzzle device pinning and most of my upper tricks. Even building a pair of heavy barrel varmint rifles with slick side uppers.

On lower will cover chasing buffer tube threads, installing buffer tube, stocks (both carbine and A2), the easy and inexpensive trigger job and installation, proper tools for installing all roll pins, takedown pins, mag catch and safety plus more. Will even show threading and installing a grub screw to hold take down pin detent spring so don't have to fight it whenever install or swap a receiver end plate don't have to wrestle getting spring in without kinking, one of the most often seen issues when people assemble a lower. At shop sell detent springs like candy and when customer comes in second or third time to get a less than dollar spring can tell they are frustrated. Some reason internet and Utube has convinced people assembling an AR on kitchen table is easy peasy and can be done perfectly by anyone first time.

Many have no idea a $400 barrel is not going to shoot as well if receiver has not been squared. Also 6.8's will break bolts inside of a 1,000 rounds on unsquare receiver and expect the 22 Nosler to be hard on bolts as well. Can work in post on bolt carrier group assembly and maintenance then the real experts can step in and impart their wisdom. I think a well structured AR assembly thread, setting up gas and buffer systems correctly, troubleshooting gas issues and extractor upgrades and replacement along with how to do a $15 trigger job on OEM unit that is good as a $79 aftermarket trigger or better would help a lot of budget builders. By time all the regular builders and retro experts impart their tricks and knowledge would be sticky worthy and may avoid the rotation of same threads over and over every month or so.

Someone else will have to cover pistol builds and odd cartridges other than 5.56, 6.8 and 22 Nosler as standardized on those three for now. Only done a couple of pistols and tore them down a while back though doing one in next month because a guy came into LGS frustrated with his pistol and had it swapped to carbine and I walked out with $10 KAC pistol setup including a Slash Heavy Buffer. Going to put a brace on and use an 11.5" barrel so will be more of a short rifle than pistol but by ATF rules will be classified as pistol. Next one of you guys that build a 9mm or other true pistol caliber AR take good pics and document your techniques for a build thread post if think this is a good idea. Someone needs to document a 458 SOCOM build, etc. Everyone put in their specialty build then users can have their parts list, tool list and idea of procedures for most popular builds right here with photos and description hopefully avoiding common pitfalls before posting the "help, my AR doesn't run" thread but a looky, looky "it's nice and it worked perfectly first time" range report.

FYI, BATF came through town and audited all the gun shops of significance. Spent two days in one, four in another and at least a day or two some others. When selling an AR bare receiver they specifically said on Form 4473 said write the word Reciever on form. Not rifle or pistol. Know we have had a lot of discussion that once a rifle always a rifle, if starts as a pistol can go either way later. So if buy a built lower it will be logged as rifle or pistol according to,configuration. But buying a blank receiver I used to ask to log as pistol on occasion so receiver was logged as such if building a pistol. Purchased two lowers yesterday from one shop and one from another that both had audits in past week and was told specifically could not write pistol on 4473 for the unit I am going to install the KAC kit. Said got some minor grief over doing that so going to hope my logs have which serial numbers were originally logged as pistols so can scavenge a lower that has pistol on its original 4473 or will have to build the pistol on a "Reciever" and let it go. BATF said till built, it's neither and shop doesn't know clients intent is what say so log it as what it is. A receiver, nothing more, nothing less so unless someone has a fresh letter from Washington with different ruling I am going by rules that a blank lower can be built into any configuration that is legal without pistol attached to its 4473.

How often do we have a gas issue thread or trigger selection thread. If we helped Files users from avoiding some of these traps might prevent lots of frustration first trip to range with a new build. Not saying I am an expert but 90% of the time my guns run immediately and other 10% a buffer swap or gas adjustment and then are 100% reliable. Have built over 100 uppers, repaired as many or more for free as enjoy trouble shooting uppers like most watch men play with balls. LGS is discussing putting me behind gunsmith counter doing uppers and trigger work more regular which will be a blast as get to see all the fubar stuff people do at home and fix it. That should result in lots of troubleshooting tips. Only done a little over three dozen complete personal builds so not a professional but have made it through most beginner mistakes and know how to solve with common tools or proper tools especially uppers as not a gun so get to take them in frequently.

Enhander
May 04, 2017, 11:22
Im not really sure how to tell if there is a problem with the gas rings on the bolt.

Heres my bolt from my S&W M&P15 that functions 100%.
http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/FE7F4814-7A03-421D-B227-C09DB7FE391E_zpswila5ge0.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/FE7F4814-7A03-421D-B227-C09DB7FE391E_zpswila5ge0.jpg.html)



...and here is the bolt from my A2:
http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/95E787FF-5CA1-4C00-8F51-EB45967F73CB_zpstalifcyg.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/95E787FF-5CA1-4C00-8F51-EB45967F73CB_zpstalifcyg.jpg.html)


I know those probably don't tell anyone much...:facepalm:

jhend170
May 04, 2017, 12:58
Im not really sure how to tell if there is a problem with the gas rings on the bolt.

Heres my bolt from my S&W M&P15 that functions 100%.
http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/FE7F4814-7A03-421D-B227-C09DB7FE391E_zpswila5ge0.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/FE7F4814-7A03-421D-B227-C09DB7FE391E_zpswila5ge0.jpg.html)



...and here is the bolt from my A2:
http://i748.photobucket.com/albums/xx123/FEARMember/Enhander/95E787FF-5CA1-4C00-8F51-EB45967F73CB_zpstalifcyg.jpg (http://s748.photobucket.com/user/FEARMember/media/Enhander/95E787FF-5CA1-4C00-8F51-EB45967F73CB_zpstalifcyg.jpg.html)


I know those probably don't tell anyone much...:facepalm:

They look fine. Hard to tell but so long as they are slightly larger than the diameter of the bolt where they ride in their channel they are fine. Your ejection wouldn't be that good either if the rings were bad. 1 more thing ruled out. So back to that spring...

hueyville
May 04, 2017, 20:59
Gas ring facing front of bolt looks compressed and smaller diameter than center and rear which look fine. Are my eyes playing tricks on me?

Enhander
May 04, 2017, 21:30
They look fine. Hard to tell but so long as they are slightly larger than the diameter of the bolt where they ride in their channel they are fine. Your ejection wouldn't be that good either if the rings were bad. 1 more thing ruled out. So back to that spring...

Got the new spring installed. I'll be going to the range this weekend to test it out.

burtman
May 04, 2017, 21:50
Run what ya brung Enhander :beer:

Enhander
May 06, 2017, 11:34
Ok, So I just got back from the range and had some favorable results. I brought another AR with me in case I had to swap parts to troubleshoot, but there was no need to shoot it. The only change that was made was swapping the crappy UTG buffer spring out for a quality one. Here are my notes:

First test round was with Wolf Ammo

-First 12 rounds. Three rounds in each mag
Troy Battlemag - Locked open
PMag G2 - Locked open
GI - Locked open
PMag G3 - Did not lock open

-Second 12 Rounds. Three in each mag
Troy Battlemag - Did not lock open
PMag G2 - Did not lock open
GI - Locked open
PMag G3 - Locked open

-Third 12 rounds. Three in each mag
All Magazines locked open


PMC XTac and Wolf Gold Mixed Brass Test.

-30 rounds.. 5 in each mag/reload/5 in two mags
All Magazines locked open

- No Failure to Feeds.

- After those initial failure to lock open, the rifle functioned 100%.

- Ejection Pattern was consistent and landed in a small pile roughly 6 feet away from the chamber of the rifle.


Im quite satisfied. Not sure if the failures to lock open were just mag related? But I was happy.

Now I do have another, somewhat unrelated question. I zeroed the rifle at 25 yards. Today I was shooting at a target at 100 yards. My mind obviously wasn't on accuracy, but I had the target down there just to have something to shoot at. If memory serves me correct I was aiming just below the bullseye of the target (or at least what I could see of it). When I went to retrieve the target there were no rounds that had hit, however I had a pretty decent group that landed about 4 1/2 inches above and about 2 inches to left of my target (it hit the cardboard my target was attached too). So at least I had a point of reference. Since I zeroed at 25 yards, I assume I should have been aiming at the 6 o'clock of the target? The 2 inches too the left was likely my improper trigger control. Should I re-zero the rifle at 50 to get more favorable results?

:bow:

burtman
May 06, 2017, 14:36
You've got a A2 upper so you could go this route http://www.armystudyguide.com/content/army_board_study_guide_topics/m16a2/zero-and-m16a2-rifle.shtml having said that 25 yards is only 22.8 meters and I imagine things can get off from 25 meters = 300 meters

Some are fond of 50 yards = 200 yards

GDavis
May 07, 2017, 10:45
Sounds like you built an Original type gun.!!

The early M16A1 manual is full of pics about how those early guns malfunctioned, and the types of jams incurred.



Pretty sure the gun worked fine until they met the humid dirty conditions of Vietnam. Type of ammo powder was changed and non-chromed lined barrels coupled with cleaning kits were not issued was a recipe for disaster. I don't think any of those early issues with the M16 have anything to do with this guys issues on his build.

GDavis
May 07, 2017, 10:47
They look fine. Hard to tell but so long as they are slightly larger than the diameter of the bolt where they ride in their channel they are fine. Your ejection wouldn't be that good either if the rings were bad. 1 more thing ruled out. So back to that spring...

But if the slots in all 3 rings were lined up that could cause issues. Be sure to position the slots in the three rings so they are not aligned.

Enhander
May 07, 2017, 12:16
But if the slots in all 3 rings were lined up that could cause issues. Be sure to position the slots in the three rings so they are not aligned.

I was wondering about that. I think two of the rings were aligned. I'll check that when I clean the gun here in a bit.

hueyville
May 08, 2017, 09:21
Worked on an AR Saturday afternoon at LGS. Had a ten round Pmag in it and bolt was locked back. When pushed mag release mag didn't drop and when pulled it out the bolt dropped and suprised me. Played with and if cycled the bolt by hand and let empty magazine lock bolt it would drop everytime mag was pulled. If pulled bolt back and manually engaged bolt catch magazine would drop free and bolt stayed where it was supposed to. Odd but did both ways a dozen times with same result.

M90A1
May 08, 2017, 10:13
Evidently, the mag follower is not actuating the bolt catch correctly. Duh! Weak mag spring, bad follower, or ?

hueyville
May 08, 2017, 10:25
Magpul magazine, aluminum G.I. and it worked flawlessly.

jhend170
May 08, 2017, 11:10
But if the slots in all 3 rings were lined up that could cause issues. Be sure to position the slots in the three rings so they are not aligned.

This sounds good in theory and has been perpetuated for years, but has proven to be false. The ring gaps are so small they can't bleed pressure fast enough to cause failure.

When I do a build I place gaps at differing positions because I've also build a small-block chevy a time or 12, but that won't cause your failure.

Enhander
May 08, 2017, 11:20
Yeah, at this point it seems to be that 10 round Pmag. Odd that its nearly new and having that issue, but it does explain a lot.

GDavis
May 08, 2017, 17:12
This sounds good in theory and has been perpetuated for years, but has proven to be false. The ring gaps are so small they can't bleed pressure fast enough to cause failure.

When I do a build I place gaps at differing positions because I've also build a small-block chevy a time or 12, but that won't cause your failure.

BUT- it HAS to be true- I read it on the internet!!

hueyville
May 08, 2017, 18:26
When install a bolt make sure the ring splits have random spacing but unless disassemble bolt carrier for some odd reason never check it again. Have habit of never disassembling bolt carrier groups even to clean. Learned a long time ago an ultrasonic cleaner cleans a BCG to same squeaky clean standards whether disassemble or not. If it doesn't make a difference then why monkey with it? Inspect carrier and bolt face for obvious cracks, lube the crap out of it and then shoot till stops slinging oil like an AMF built Harley from early 70's with original seals. Most of my zombie guns get a half mag to full mag run after cleaning to ensure assembled properly or didn't develop an issue while in pieces.

Enhander
May 22, 2017, 08:20
If anyone is interested, heres the 3 videos I made going over my A2 testing:

Part 1: https://www.youtube.com/watch?v=8UdQs7GWZGM
Part 2: https://www.youtube.com/watch?v=sUsnqZWyypk
Part 3: https://www.youtube.com/watch?v=c8gAVDS6bsc&t=7s

Bonac9
May 22, 2017, 09:35
One of the times I've had consistent failures to lock open was with a 10 rd PMAG mag. I question if the springs are strong enough.
One way to test your gas rings is to take out the bcg, pull the bolt to the forward position, and stand it on the bolt head on a hard flat surface. With good rings gravity should not cause the bolt carrier to settle, and it should stay extended. Needless to say, it should be clean, and I don't know if this works for the light weight carriers or not.

Yeah, at this point it seems to be that 10 round Pmag. Odd that its nearly new and having that issue, but it does explain a lot.

M90A1
May 22, 2017, 10:34
I hope I'm not being overly critical, but since when did the A2 have triangular hand-guards and the open prong flash-hider? I thought the three prong flash-hider ended with the advent of the A1, and the triangular hand-guards ended with the introduction of the A2.

Enhander
May 22, 2017, 10:41
I hope I'm not being overly critical, but since when did the A2 have triangular hand-guards and the open prong flash-hider? I thought the three prong flash-hider ended with the advent of the A1, and the triangular hand-guards ended with the introduction of the A2.


No, you're not being critical at all. I thought about that. Its more-so an A1/A2 hybrid. The upper is A2 so I just went off that. I couldn't find an A1 upper at the time so I just went with the A2.

Enhander
July 23, 2017, 08:20
Ok gents, need some more help. I had a chance to hit the range again and zero at 50. That went fine..its when I bumped out to 100 yards that the issues started. I'm fairly certain that I need to adjust my front sight a bit...I think. I explain whats going on in the video below. In order to land hits on the target, my point of aim was a good bit lower than the target itself...

As I state in the video, I can never remember what direction I need to adjust the front sight. I know its opposite of point of impact (i.e. If Im shooting low..move the sight up..) But for some reason I can't get that through to my brain...:facepalm:

Any tips are appreciated! I am at your mercies! :bow:


https://www.youtube.com/edit?o=U&video_id=IC_dtS24VNM

M90A1
July 23, 2017, 08:52
If you're impacting low compared to your point of aim, raise the rear sight or lower the front sight to correct the point of impact.

Enhander
July 23, 2017, 09:46
In this instance I was hitting higher. Point of aim was a few inches lower than the point of impact. Now that I think of it, I was aiming about 4 inches from the bottom of the target. Doing so put my rounds in the center of the target. So in total I was aiming about a foot low or so.

It was my understanding that I shouldn't really adjust my rear sight elevation... but if course I could have been given misinformation.

I know the front sight has an indicator on which direction is Up. If I adjust in that direction am I moving my point of aim down?

Also, the sight is spot on at 50, which confuses me why it's so off at 100.

M90A1
July 23, 2017, 10:41
http://www.armystudyguide.com/content/army_board_study_guide_topics/m16a2/zero-and-m16a2-rifle.shtml

Tuscan Raider
July 23, 2017, 10:58
Sight post up moves POI down, and vice versa.

Invictus77
July 23, 2017, 11:26
Also, the sight is spot on at 50, which confuses me why it's so off at 100.

Are you shooting from a consistent rest and not tweaking the barrel somehow? With a zero at 50 yds, I would expect the POI at 100 to be 1.5"-2" high with the iron sights, not a foot high as you describe. Something is very odd or there is perhaps some missing info ????

mikeuniform
July 23, 2017, 14:26
One method for "battlefield zero".

https://www.youtube.com/watch?v=a5QUszJA_Ow

Then to add to the zeroing, google "Revised improved battlefield zero".

FWIW, if you're shooting different brands of ammo, your POI may vary. Could be confusing while zeroing.

fly2.0
July 24, 2017, 05:56
I use a bore lazer ,at 100 ft. then fine tune at the range . @ 100 - 200 yards This will save you (me) a lot of ammo & time .

Enhander
July 24, 2017, 07:17
Ammo has been consistent. Wolf .223 55 grain FMJ. It's what I run out of all my 5.56/.223 rifles.

Reading through the article, it mentions that for 0-200 meters you should use the large aperture. I've been using the small aperture..should I switch that?

For a rest I've been using a foamactionsports.com rest. It holds the rifle fairly well..but perhaps I need to get a better rest for testing.

I've been shooting for years now, I don't know why I'm having so much trouble getting things to co-operate. Embarrassing it is...:facepalm:

The first AR I bought (My S&W M&P15) was spot on right out of the box...it wasn't until I started building ARs that I ran into issues with iron sights. However, I guess the best way to learn how to fix a problem is by troubleshooting and working through it.

MAINER
July 24, 2017, 09:12
You will have a a POI shift if you change apertures. There is an offset of .014" or 2.5 MOA, .017" or 3.06MOA, and .024" or 4.36MOA depending on which rear sight you have. I would guess you would have one of the latter two.

This offset is based on a 20" barrel and using M855 ammo at 100 yards, so it would be a bit different for a 16" or for different ammo.

Normally, you would zero the large aperture for 200yds. and the small aperture for 300yds.

I don't do Service rifle competition, so my practice has always been to zero my sights to place my shots about 2.0" high at 100 yds. with the small aperture when using iron sights.


Personally, I zero my sights at 25 yds. using the small aperture, then bolt some form of 1-4x or 1-6x Scope to the top of the thing. Works for me.

No reason for embarrassment, With all the variations of sights, barrel lengths, twist, ammo and such, it do get complicated. Unless of course, you were to shoot one rifle, with one set of sights, using the same ammo and practice with the same setup diligently for eternity. "Beware the man with one rifle".
That wouldn't be me, no fun there. ;)

hueyville
July 24, 2017, 11:44
If have BUIS type sights on rear of upper receiver and front on a free float picatinny rail type forearm all kinds of loopy issues can occur. First is if forearm pic rail is not 100% parallel and level with upper receiver picatinny rail then sights will not be properly aligned and as range increases windage error will increase. Have put sights on and set with laser bore sighting device in shop then fine tuned at 25 yards at range. Then if off at 50 yards make no adjustment and shoot at 100. If error increases in same direction you have first sign of what issue may be. If your issue is with elevation it's harder to diagnose.

First trip to range I take a few tall targets with inverted "T" or "cross" drawn on them and actually use level to make sure are installed on target stand perfectly level. Once rifle is sighted in as want then twist elevation adjustment on scope and sights 10 clicks down at a time till bottoms out. Return to proper sight in setting and dial up elevation 10 clicks at a time always aiming at point where your squared and leveled lines intersect. If from bottom to top the lowest shot is "x" inches left or right of line and at top of target shot is equidistant opposite side of vertical line every 10 clicks then know your scope is not level. Be ready to reset scope so dialing elevation adjustments in field doesn't throw a important shot totally off your target.

Some free float forearms are not as rock solid as should be. If any flex in forearm or wiggle in way it mounts based on pressure placed it will cause front sight to move. Have seen rifles that forearm had so much flex sights could be zeroed sitting on rifle rest then if take off rest and use sling to steady your standing shots the leverage put on forearm will pull front sight totally off zero. Some of the free float designs that attach to barrel nut with screws are bad about this. The thread on type seam less prone to this issue and more metal for stiffness seems to reduce this also. Wasn't thinking on one build and installed BUIS sights reversed from each other. Way they were made doing so caused them to not be parallel to line of bore thus as range increased shots moved farther from point of aim. Soon as turned front sight around issue went away. Look at some of the tricks Service Rifle Shooters use to keep from flexing barrel and sights when lean on sling for stability or change grip pressure on forearm as transition to different shooting positions. Will help you understand how minute change in pressure on forearm or alignment of sights to bore can throw entire effort into the toilet.

Enhander
July 24, 2017, 18:12
So I noticed something when I looked at the front sight today. I don't know how I missed it when I was at the range..but apparently the front sight blade was a good 75% (if not more) down into the front sight itself. I think when I was adjusting it at the range, I was adjusting it in the wrong direction. As per the manual that was linked a few posts back, I moved the front sight blade to make it level with the front sight base.

I got my laser bore sighter (I used two different ones..one that you put in the end of the barrel as well and one that you put in the chamber). Both of them seem to look right when I look down the sight.

Im going to try to get back out to the range this weekend and see what happens.

hueyville
July 25, 2017, 05:35
Hate the ones that go in bore as flash hider usually keeps them from inserting far enough to ensure true with bore. Have big pile of the ones that fit in chamber and caliber adapters. If light passes from chamber down bore and comes out assume it is reasonably aligned. I would do my best to adjust front sight and leave rear in middle of its adjustment range. Then if need to adjust dope in field for extended or short range can count clicks or turns to rough in sights for different range.

Dirt1042
July 27, 2017, 01:25
BUT- it HAS to be true- I read it on the internet!!

Its what the Marine Corps taught in marksmanship training. Stagger the gas rings.

Dirt1042
July 27, 2017, 01:29
So I noticed something when I looked at the front sight today. I don't know how I missed it when I was at the range..but apparently the front sight blade was a good 75% (if not more) down into the front sight itself. I think when I was adjusting it at the range, I was adjusting it in the wrong direction. As per the manual that was linked a few posts back, I moved the front sight blade to make it level with the front sight base.

I got my laser bore sighter (I used two different ones..one that you put in the end of the barrel as well and one that you put in the chamber). Both of them seem to look right when I look down the sight.

Im going to try to get back out to the range this weekend and see what happens.

How is the windage on the delton? The A2 i built a few years back. They assembled the upper and i believe over torqued the barrel because my rear sight is drifted all the way to the side to hit center mass. Or they didnt time the front sight post and its canted.

hueyville
July 27, 2017, 06:33
How is the windage on the delton? The A2 i built a few years back. They assembled the upper and i believe over torqued the barrel because my rear sight is drifted all the way to the side to hit center mass. Or they didnt time the front sight post and its canted.

Whack front sight tower with a rubber hammer and see if it helps, not too hard but firmly.

Enhander
July 29, 2017, 07:48
Ok, a bit of an update here:

A2 Testing Continues... (https://youtu.be/nKugXsbAEmI)

Hit the range yesterday despite the nasty weather we were having. At least I had the range all to myself. Anyway, It appears as though things are corrected now. At least from what I can tell, however I'd like everyones input.

The A2 is now hitting POA/POI at 100 yards. My question is, should I adjust the sights so its hitting an inch or so high at 100 or leave it where its at? I didn't intentionally zero it for 100. All I really did to correct the problem from last time was leveling out the front sight post. Should I tune it a bit better so Im hitting spot on at 50 and an inch high at 100?

Thanks for all the help everyone, your feedback and tips are greatly appreciated. :bow:

Invictus77
July 29, 2017, 07:56
A couple inches high at 100 makes it pretty flat out to 300. Play around with this calculator and see what makes sense for your intended use.

http://ballisticscalculator.winchester.com/

nvcdl
July 29, 2017, 09:33
Ammo has been consistent. Wolf .223 55 grain FMJ. It's what I run out of all my 5.56/.223 rifles.



Are you running Wold Gold or the cheaper steel case stuff? I've heard of people having similar issues with the steel cased ammo.

Enhander
July 29, 2017, 10:29
Are you running Wold Gold or the cheaper steel case stuff? I've heard of people having similar issues with the steel cased ammo.

Ive considered switching to Wolf Gold. Although I've been using the steel cased stuff for a long time without issue until now.

idsubgun
July 29, 2017, 11:05
First, I sight ALL my rifles to a couple inches high at 100 yards. As was mentioned, it makes about every rifle cartridge good-to-go out to 300-400 yards.


Second, I don't run steel cased ammo in anything except those firearms originally designed for it (AK's, Makoravs, etc.). I've had two rifles brought into my shop that had live steel cased ammo stuck in AR-15's. The only thing you can do is use a long steel rod and beat it out of the chamber. Smacking on a live round is a high pucker factor, to say the least. For this reason, I stay away from steel cased ammo in AR's no matter what people say about having good luck with it. Brass cased .223/5.56 ammo is dirt cheap these days, why chance a stuck case?

nvcdl
July 29, 2017, 16:48
Ive considered switching to Wolf Gold. Although I've been using the steel cased stuff for a long time without issue until now.

Supposedly the steel cased Russian ammo is not as hot and can cause short strokes...may be part of the issue...

M90A1
July 29, 2017, 17:24
Supposedly the steel cased Russian ammo is not as hot and can cause short strokes...may be part of the issue...

Have you watched any of his videos? The rifle, firing the steel cased ammo, appears to be functioning most excellently.

hueyville
July 29, 2017, 17:47
Only run steel ammo in combloc rifles. As to 100 yard point of aim I base it on ammo use, intended target size and then calculate maximum point blank range based on the two. For a 16" 1:9 twist rifle used to lob 55 to 62 grain milsurp at a man size target the hold over or height sights set to at 100 yards will be much different than a rifle with 24" 1:12 twist barrel shooting 40 to 50 grain bullets at crows or a 20" 1:7 twist barrel used to launch 69 to 77 grain bullets at coyote and ground hogs. Then have the option of using a ballistics app to calculate dope on every shot using a quality range finder and annenometer linked to ballistics computer via Bluetooth. How much hold over? We know you have a 20" 1:7 barrel but is your intended target man size, deer, coyote or Prarie dog? Launching 40, 50, 55, 62, 69, 77 or 90 grain bullets?

Simplified explanation.

https://azrifleman.com/basic-rifle-marksmanship-brm-series-twists-and-zeros/

One of many Point Blank Calculators. This is basic, I use a proprietary piece of software that calculates all possible factors including voodoo and phases of the moon.

http://www.shooterscalculator.com/point-blank-range.php

My fighting rifles are set up using 62 grain bullets with 10 inch kill zone. If drop to 55 or jump to 69 the rifle is not too far off but math has to be done to adjust shot. With a 20" barrel, 62 grain M855, if set sights 4.35" high at 100 yards you will have a 280 yard maximum point blank range on a person. This means no matter where a person is if between 0 and 280 yards hold center of mass and your bullet will enter into vital organs. A crow is going to shorten your point blank range significantly. Most of my varmint AR's are 1.5" to 2.5" high at 100 and my ballistics calculator knows what the adjustment is for each rifle and for each load. Whichever rifle choose for day tap on rifle choice and ammo choice in drop down menus and wait till I see a varmint that needs to die. I zap target with range finder and intantly a firing solution like this pops up on face of tablet or smart phone figuring in distance, humidity, spin drift, wind, Coriolis Effect, altitude, etc. The app even has the reticle of the scope saved and thus it's so simple only real way to miss is to screw up on the shooters end as math is spot on.

http://i66.tinypic.com/2cctk6v.jpg

With iron sights would decide what my primary varmints kill zone size is, choose my load and calculate maximum point black and set sights for it. Then print a paper chart that gives finer resolution of hold over at different ranges for smaller targets and more precise shots. Tape chart to stock and it's always there for referance.

Enhander
August 01, 2017, 06:54
Typically, with most of my rifles, I try to keep them accurate enough to hit a man sized target at 100. Not that I expect to ever have to use it for that purpose, but I want to peace of mind to know that if crap hits the fan and I have to use one of my rifles to defend my family or myself, I can do so both up close and at distance.

I thought about buying a few hundred rounds of the Wolf Gold (55 grain FMJ) to test. I've shot it before and its good stuff. However, I've not ran into issues with the Wolf steel cased so I never switched over. I'll check out that calculator soon.

I think what I'd like to do now is get a better trigger for the A2 and retest. The trigger that is in it now is pretty atrocious. I've shot a lot of ARs that have had stock triggers...this trigger just seems worse than average. I believe its an Anderson trigger kit. I typically love Anderson stuff, I've had really good luck with it. This trigger just seems to be junk though. I have ALG Defense triggers in my main AR and my SIG 716 and they perform great. That's what I'll likely get for the A2.