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Conagher
June 09, 2017, 01:30
Here is my latest L1A1 build. I still have to get the flash hider pin pressed in, a wood carry handle, and a .254 LS for it;

http://i.imgur.com/pyWHIrKh.jpg?1

http://i.imgur.com/KAl3mHKh.jpg

It has a DSA L1A1 Brit Receiver, C1A1 lower receiver and rear sight, DSA charging handle, FSE HTS, FA gas piston, and a Yellowhand furniture set.

OLDMANPBK
June 09, 2017, 02:03
Nice. :beer:

pl521
June 09, 2017, 02:07
Wow You did good. L1A1 turned out very nice! Congratulations on a job well done.

01BIRDDOG
June 09, 2017, 07:05
Beautiful L1A1 you have there and good job on the build.

VALMET
June 09, 2017, 07:42
Nice-looking aussie!

jam762
June 09, 2017, 08:07
Very nice indeed!

Invictus77
June 09, 2017, 09:30
It is hard to beat the look of a wood furniture L1A1. Well done sir :cheers:

Conagher
June 09, 2017, 09:44
Thanks fella's!

IIRC I think the only Aussie part is the handguards. I wanted a Brit handguard, but this set Yellowhand had for sale, had the Aussie version.

With the C1A1 lower, Brit barrel, front sight/gas glock, carrier, bolt, and Buttstock, and Aussie handguards, I guess it's paying tribute to all three countries :fal:

lostmybearing
June 09, 2017, 10:08
It looks great! Excellent work!

Vulcanator
June 09, 2017, 18:18
Looks absolutely awesome, did the receiver give you any build issues?

Andy the Aussie
June 09, 2017, 18:22
Good looking rifle mate !!!! :bow:

yellowhand
June 09, 2017, 19:26
That is down right pretty!!!!!:bow:

Guess I need to break down and cut some more wood handles,been a while since I ran a batch.:wink:

hkshooter
June 09, 2017, 20:08
That is down right pretty!!!!!:bow:

Guess I need to break down and cut some more wood handles,been a while since I ran a batch.:wink:

Wood handles? As in carry handles? I need one for the wood set you did for me.

jam762
June 09, 2017, 20:30
Is there a source for the caps?

Conagher
June 09, 2017, 20:38
Looks absolutely awesome, did the receiver give you any build issues?

The DSA receiver only has a minor issue with the mag release being a little bit stiff, but I think after some usage it will free up and work like normal.

Conagher
June 09, 2017, 20:39
That is down right pretty!!!!!:bow:

Guess I need to break down and cut some more wood handles,been a while since I ran a batch.:wink:

Yes, please do and let me know as well.

Thanks!!!

yellowhand
June 09, 2017, 22:40
Wood handles? As in carry handles? I need one for the wood set you did for me.

""Is there a source for the caps?""




Yep, tha carry handles.
Got everything I need, was just waiting till my new shop got put up, but with delays, might as well and break out everything and get some done.

No on the end caps.

I will cut some direct replacements for folks that have buggered up ones, but have the original metal end caps and also a modified one that simply goes in place, held on with small c clips on the hanger rod.

I cut some test samples a year ago, and actually like the appearance of the non metal end ones better. Has all the little ribs etc, but even on the ends vs the taper with the metal caps.

Will dig them out and post up some photos.

And Mark/Gunplumber and I looked high and low for a way to make the end caps, and its just not worth it vs the cost.

muttman
June 10, 2017, 06:05
Yellowhand,
Please keep us informed on the wood handels, I need one for my ausy build.
Coangher,
Nice looking build.
Muttman

Hammer63
June 10, 2017, 21:07
Great looking rifle man. :whiskey:

Conagher
June 18, 2017, 22:49
I got my .254 LS from GunThings and it is done except for a L1A1 sling and a wood carry handle.

I would have fired some first rounds through it today while up at my family's ranch on the Mtn, but I was helping my Dad figure out his clutch and brake pedal bracket that has to be made for his custom 69 Peterbilt long narrow nose baby window pickup.

SteelGreyML
June 19, 2017, 00:09
Nice looking rifle!

BUFF
June 19, 2017, 21:18
" but I was helping my Dad figure out his clutch and brake pedal bracket that has to be made for his custom 69 Peterbilt long narrow nose baby window pickup."

Now, THAT we need pictures of!

enbloc8
June 19, 2017, 21:23
""Is there a source for the caps?""




Yep, tha carry handles.
Got everything I need, was just waiting till my new shop got put up, but with delays, might as well and break out everything and get some done.

No on the end caps.

I will cut some direct replacements for folks that have buggered up ones, but have the original metal end caps and also a modified one that simply goes in place, held on with small c clips on the hanger rod.

I cut some test samples a year ago, and actually like the appearance of the non metal end ones better. Has all the little ribs etc, but even on the ends vs the taper with the metal caps.

Will dig them out and post up some photos.

And Mark/Gunplumber and I looked high and low for a way to make the end caps, and its just not worth it vs the cost.

If it's any help, I have a couple of Aussie carry handles wherein the original "star washer" end cap (I think that's what it's called?) is held in place by either a split pin (through a hole drilled in the "wire") or a small nut.

Conagher
June 20, 2017, 20:08
If it's any help, I have a couple of Aussie carry handles wherein the original "star washer" end cap (I think that's what it's called?) is held in place by either a split pin (through a hole drilled in the "wire") or a small nut.

Any pics of them?

Thanks!

Conagher
June 25, 2017, 20:31
I've taken the SLR out and fired some rounds through it, but it has a FTE the spent case, FTF the next round.

On the L1A1 which direction does the gas plug need to be in for normal shooting vs grenade launcher mode? I can't remember which way it's supposed to be.

It has a brand new gas piston and I have the gas set at 5 on the regulator. The gas tube is not screwed all the way in, and it is pinned and cannot back off out of the Front gas block.

Thanks :fal:

Vulcanator
June 25, 2017, 20:38
I've taken the SLR out and fired some rounds through it, but it has a FTE the spent case, FTF the next round.

On the L1A1 which direction does the gas plug need to be in for normal shooting vs grenade launcher mode? I can't remember which way it's supposed to be.

It has a brand new gas piston and I have the gas set at 5 on the regulator. The gas tube is not screwed all the way in, and it is pinned and cannot back off out of the Front gas block.

Thanks :fal:Make sure the gas plug is installed with the slot facing upwards.

OLDMANPBK
June 25, 2017, 20:39
The slot on the outside of the gas plug should face up for normal shooting.

Conagher
June 25, 2017, 20:52
The gas plug has the slot facing upwards.

The gas piston spring is the correct one.

Any other ideas?

Thanks!

OLDMANPBK
June 25, 2017, 20:58
Did you follow the correct procedure for setting the gas regulator?

Conagher
June 25, 2017, 21:01
Not really, I just set it on 5 to see how it would do.

OLDMANPBK
June 25, 2017, 21:42
Bear of Sinai will show you. :biggrin:

https://www.youtube.com/watch?v=vDIASnwvC3c

Conagher
July 19, 2017, 21:55
It doesn't matter which setting the gas regulator is in, it still won't cycle another round in, and the gas piston moves freely.

Can someone explain the gas tube installation process? I have it pinned with the gas tube pin so it can't move.

Thanks!

OLDMANPBK
July 20, 2017, 01:51
Sorry to hear that your still having problems. These are two great threads. One is a build thread that will help you with the gas tube and one is for troubleshooting. Good luck.
http://www.falfiles.com/forums/showthread.php?t=387858
http://www.falfiles.com/forums/showthread.php?t=108077

Conagher
July 24, 2017, 23:38
I took it apart and cleaned the gas tube and put it all back together and even with the gas regulator on 3, it still fails to move the bolt & carrier back to chamber another round. The gas block hole from the barrel is open and not obstructed, and I have the gas tube backed off a turn and a half from being bottomed out, with the two bleed holes at 8 and 4 o'clock. The gas plug is in correctly with the groove facing up. I have a brand new Falcon Arms gas piston in it as well.

I've noticed that just cycling the bolt and carrier back to chamber a round, it seems as though it has more pressure on the springs in the butt stock tube, when compared to my STG58.

Can that be the source of my cycling issue?

Thanks,

Doug

yellowhand
July 25, 2017, 00:12
I took it apart and cleaned the gas tube and put it all back together and even with the gas regulator on 3, it still fails to move the bolt & carrier back to chamber another round. The gas block hole from the barrel is open and not obstructed, and I have the gas tube backed off a turn and a half from being bottomed out, with the two bleed holes at 8 and 4 o'clock. The gas plug is in correctly with the groove facing up. I have a brand new Falcon Arms gas piston in it as well.

I've noticed that just cycling the bolt and carrier back to chamber a round, it seems as though it has more pressure on the springs in the butt stock tube, when compared to my STG58.

Can that be the source of my cycling issue?

Thanks,

Doug


Take your metric lower and slap it on the L1A1 upper and see if that works.

gunplumber
July 25, 2017, 09:35
I have the gas tube backed off a turn and a half from being bottomed out, with the two bleed holes at 8 and 4 o'clock.

Why would you do that? Screw it all the way in. back it off until the holes are level (no more than 1/4 turn). Since it's a FAL gas tube on an L1A1, the hole orientation doesn't matter up or down (L1A1 are 3 and 9 o'clock).

L1A1s lose gas with wear more than FALs. close regulator all the way to get to a start point. While it should cycle on 4, it may need the gas port reamed to make that happen.

You have not mentioned having to mortar the the rifle to extract an expanded and rechambered round (gas failure prior to ejection) but a failure to chamber next round. Which suggests complete ejection?

images no longer available.

Conagher
July 25, 2017, 20:26
[QUOTE=gunplumber;4455232]Why would you do that? Screw it all the way in. back it off until the holes are level (no more than 1/4 turn). Since it's a FAL gas tube on an L1A1, the hole orientation doesn't matter up or down (L1A1 are 3 and 9 o'clock). - I have a L1A1 gas tube on it and after looking at the holes, they are at 9 and 3 o'clock position.

L1A1s lose gas with wear more than FALs. close regulator all the way to get to a start point. While it should cycle on 4, it may need the gas port reamed to make that happen.

You have not mentioned having to mortar the the rifle to extract an expanded and rechambered round (gas failure prior to ejection) but a failure to chamber next round. Which suggests complete ejection? - No, I have to manually move the charging handle back to eject the spent case and load the next bullet.

images no longer available.- due to photobucket becoming photofuckers with their communist charging for 3rd party hosting now. I haven't looked for a new photo hosting site yet.

Mark, thank you for your invaluable experience and knowledge with these rifles!!!! I proudly wear my Arizona Response System FAL t-shirt when I go out in public :biggrin:

yellowhand
July 25, 2017, 20:41
""due to photobucket becoming photofuckers with their communist charging for 3rd party hosting now. I haven't looked for a new photo hosting site yet."""

This one far better than photobucket, cost nothing, and its pretty darn easy to work.

http://imgur.com/

Before you get this one working, send your photos to me direct and I'll post for ya here.

Conagher
July 25, 2017, 23:02
""due to photobucket becoming photofuckers with their communist charging for 3rd party hosting now. I haven't looked for a new photo hosting site yet."""

This one far better than photobucket, cost nothing, and its pretty darn easy to work.

http://imgur.com/

Before you get this one working, send your photos to me direct and I'll post for ya here.

Thanks buddy :D

I've heard about imgur.com but never looked into them. I'll set up an account right now so I can post pictures again.

I think I might have found the problem though.

Here is the L1A1 mag fully seated in the receiver;

http://i.imgur.com/weJnsZ9h.jpg?1

This is what happens after some single shots, it's like the carrier/bolt move back just a little bit;

http://i.imgur.com/B28EPmPh.jpg?1

I've had the gas regulator from fully closed to fully open and settings in between, and still the same single shot results;

http://i.imgur.com/uw9lqYxh.jpg

I'm assuming this is a L1A1 gas tube as it has the machined step towards the rear a few inches in front of the gas nut;

http://i.imgur.com/q5W2r7Oh.jpg?1

This is the gas plug that came with the kit, so I hope it's the correct one;

http://i.imgur.com/f1mHDRlh.jpg

The new Falcon Arms gas piston pops out of the gas tube on its own when I remove the gas plug;

http://i.imgur.com/f2UAdKTh.jpg?1

Here is everything as it's on the rifle. The gas tube nut has E62 on it, so it looks to be a L1A1 part;

http://i.imgur.com/kRY6kiQh.jpg?1

This is what it looks like with the gas tube fully set in the gas block with just the gas nut unscrewed. You can see it looks like maybe my front gas block is bent a little because it makes the rear end of the gas tube point down towards the barrel, and I have to manually lift it up some to get the gas tube nut screwed into the receiver.

http://i.imgur.com/Wq9gAiUh.jpg?1

As stated before, I cleaned the hell out of the gas tube with it off the rifle, and the new gas piston .431 diameter - will just slide right through it without any binding or issues. But with the gas piston spring removed from the gas piston, and the gas tube all the way threaded into the gas block, and the bleed holes at 9 and 3 o'clock, the gas piston will not slide all the way down on it's own without binding up on the gas tube.

This is as far as the gas piston will travel into the gas tube without the gas piston spring on it, and the gas tube and gas tube nut installed. I have to push it down with a little bit of resistance felt right directly after the gas block to get it to drop down more, and then it will free fall down without binding;

http://i.imgur.com/nbKAW9Yh.jpg

The gas tube doesn't look bent itself, and I know for a fact that the gas port hole in the barrel up through the hole in the gas block is open without any obstructions.

yellowhand
July 25, 2017, 23:18
OK, you're almost there with imgur.

Go back to your original post above and delete those large ass photos!:rofl:

Then open up imgur, pick the picture you want to post, THEN look down on the far right hand side of the pop up window with the picture, and click on large thumbnail, then go up to HTML hit copy button, then right click copy the link that shows up to the left of COPY.

The pictures will then come out normal size!

Took me a while to find the size thingy on bottom right and which one to pick.:rofl:

yellowhand
July 25, 2017, 23:19
Never mind, ya already done it!:biggrin:

Conagher
July 25, 2017, 23:50
What is the next step? Different gas block?

Conagher
July 25, 2017, 23:56
The gas piston will go down to about here which is right at the tail end of the gas block for depth, before you have to push it down with a little bit of pressure with a small screwdriver;

http://i.imgur.com/Jae3Edsh.jpg?1

yellowhand
July 26, 2017, 00:01
Mark should see these photos tomorrow.

Conagher
July 26, 2017, 00:02
Here's the gas tube to gas block orientation internally;

http://i.imgur.com/UsP1fKBh.jpg?1

Conagher
July 26, 2017, 00:13
I think it has to be either the front gas block is tweaked down at the rear of the block, how I don't know, or the gas tube I got from hkshooter here is tweaked just a little bit or something of that sort.

Here is where the gas tube nut naturally ends up and I have to lift it up .058" to get it to thread into the receiver;

http://i.imgur.com/fZIbUIWh.jpg?1

Conagher
July 26, 2017, 00:20
Here's looking down thru the top gas block hole for the regulator and looking down thru the gas hole in the bottom of the gas block and into the barrel;

http://i.imgur.com/VMD81Buh.jpg

Conagher
July 26, 2017, 00:39
I'm able to stick a small drill bit clear thru the gas block holes and see the bit in the barrel's bore;

http://i.imgur.com/DsLaz7Ih.jpg

pl521
July 26, 2017, 03:19
Ive had similar issue with having to apply small pressure to the piston to get it to go down the gas gas block. Recommend checking the gas tube front end for metal burrs that may be impeding the piston head. With the gas tube and piston out, drop the piston into the gas tube and check for any binding; the piston should drop into te gas tube freely. Sometimes, when a gas tube is over tightened into the gas block, metal on the end of the gas tube is compressed, resulting in small metal burrs on the inside edge that may contact the piston and not allow it to cycle properly. I've used a semi rounded miniature file to smooth out the inside edge of the gas tube to relieve and rid of the metal burrs. Can also use a wooden dowel wrapped with sandpaper. Good luck. Hope this helps.

gunplumber
July 26, 2017, 08:55
The gas piston will go down to about here which is right at the tail end of the gas block for depth, before you have to push it down with a little bit of pressure with a small screwdriver;

It's hard to tell from the pics (they are good pics, I just can't tell anything from them). It is possible that the sharp corner at the entrance to the gas tube is catching on the piston. I use a case deburring tool or a crown chamfer tool to cut a slight bevel at the mouth of a gas tube, particularly if I have to shave it back a thread or so to get good timing.

Try this. <ul>

Take gas tube out.

<li>install piston backwards into block.
Passes through ok, not the block.

<li>Drop piston through disassembled gas tube. Passes through, not the tube. If it is the tube, and it's in the first part (before vent holes), put piston head in first section and squeeze gently in vise. Rotate a bit and repeat. Repeated light to moderate squeezing of a round tube over a round mandrel will help to straighten out any dents. For the rest of the tube, diameter is slightly larger than piston head so you'd need a fitted mandrel.

<li>Pass piston through carry handle nut.

<li>Install gas tube w/o pin, repeat. Yes, your tube is slightly bent, but

<li>install pin and repeat

</ul>

This should isolate, by testing each part one at a time.


I have an old piston ground down slightly with a handle welded to it. I use this to push piston and make sure it travels freely before installing gas plug. I've found it useful to do every time, because it takes 10 seconds. Having failed to do it sometimes, I end up wasting a range trip for testfire, only to find the piston binding during live-fire.

Conagher
July 26, 2017, 09:47
Mark, thank you for your expertise!!!

I took it apart again last night. I will look for any burrs on the end of the gas tube this evening. When I had the gas tube out a couple days ago, the gas piston would just fall thru the gas tube without binding up. I will check it out again this evening and report back.

yellowhand
July 26, 2017, 13:14
I recognize that wood set, looks damn nice on your rifle, so get that thing running right!!!!!:D

Riddbits
July 26, 2017, 16:29
I had a similar problem with one of my rifles. Turned out that the gas plug had been sand blasted and the chrome was no longer on the end of it that goes into the block. That made it a smaller diameter by a few thousandths, but that was enough to change the tolerances. I was getting too much blow by and the action was short cycling. It would fire the round, start the extraction, but then short stroke and send the fired case back into the chamber. I got a new gas plug that was NOS and the issue went away for the most part (still not entirely sure, but it cycles now).

May not be the same issue you are having, but the picture of your gas plug sure looks like there is a lot of fouling around the shank and lugs. Have you measured the diameter of the shank and the opening of the gas block? Is it still chromed?

Conagher
July 26, 2017, 18:57
I just tried a different gas tube, and the gas piston does the very same thing and stops at the same spot as with the other gas tube, so I don't think the gas tube is the problem.

This tube points down like the original when it comes to the gas tube nut having to be lifted the same amount as with the other gas tube.

I just checked the gas piston with both gas tubes, and it will slide all the way through both of them and drop to the floor if I let it.

Trypcil
July 26, 2017, 19:35
Have you shot it without the dustcover?
Does the gas rod without a spring drop through easily into the receiver, from the vertical - are you sure of timing?
Does the Carrier move freely in the rails? Is the rat tail wobbly?
The recoil tube is not bent or inserted without the lower bevel positioned correctly?
The recoil springs are clean of gunk, and very lightly oiled?
Holding the rifle by the pistol grip, barrel away from you at arms length does she look off true?
It does this with all magazines Brit or metric?
What Hammer is in the rifle, what about the Hammer spring assembly - original Brit?
Just interested!

Conagher
July 26, 2017, 21:45
Have you shot it without the dustcover? - Yes, and no difference. It does exactly the same thing.

Does the gas rod without a spring drop through easily into the receiver, from the vertical? - It will drop down all the way vertical 9 out of 10 times. I had to clean the inside of the gas tube a lot.

Are you sure of timing? - Yes, I had timing rods to time the barrel to the receiver, and the gas tube is not canted left or right from the center of the gas tube nut hole in the receiver.

Does the Carrier move freely in the rails? - Yes, like butter.

Is the rat tail wobbly? - No, not at all.

The recoil tube is not bent or inserted without the lower bevel positioned correctly? - It was on the C1A1 receiver that I got from a fellow member here, so I'm assuming it shot fine on his L1A1.

The recoil springs are clean of gunk, and very lightly oiled? - Yes, no gunk, and lightly oiled.

Holding the rifle by the pistol grip, barrel away from you at arms length does she look off true? - It looks like a regular built FAL/L1A1.
It does this with all magazines Brit or metric? - Yes.

What Hammer is in the rifle, what about the Hammer spring assembly - original Brit? - Hammer is FSE, and the spring is original Brit.
Just interested!

I shot it with the regulator totally closed and still the same results. I swapped my STG58 lower onto the L1A1 upper, and still the same results.

The pissy thing for me is that I paid a fellow member here $550 for the incomplete L1A1 kit, and then $75 for the missing parts needed, and this fucker will not run like a FAL rifle should. $550 for the DSA Brit cut L1A1
receiver, $175 for the wood furniture, the C1A1 lower receiver, FSE hammer and trigger, Falcon Arms gas piston, DSA charging handle, and the C1A1 rear sight. I have like $1,904 invested into it and it's a single shot rifle at the moment.

This is not my first FAL/L1A1 build, but this is the first one that I've built that won't run correctly.

Vulcanator
July 26, 2017, 21:56
Is the piston the correct length? I don't know what the correct length is, perhaps a DSA piston (which runs in my L1A1) might work better?

Conagher
July 26, 2017, 22:08
It's hard to tell from the pics (they are good pics, I just can't tell anything from them). It is possible that the sharp corner at the entrance to the gas tube is catching on the piston. I use a case deburring tool or a crown chamfer tool to cut a slight bevel at the mouth of a gas tube, particularly if I have to shave it back a thread or so to get good timing.

Try this. <ul>

Take gas tube out. - Done

<li>install piston backwards into block.
Passes through ok, not the block. - passes through no problem reversed or normal direction. There is a little bit of play between the gas piston head and the gas block. Is there supposed to be any play?

<li>Drop piston through disassembled gas tube. Passes through, not the tube. - passes through fine without any binding.

If it is the tube, and it's in the first part (before vent holes), put piston head in first section and squeeze gently in vise. Rotate a bit and repeat. Repeated light to moderate squeezing of a round tube over a round mandrel will help to straighten out any dents. For the rest of the tube, diameter is slightly larger than piston head so you'd need a fitted mandrel.

<li>Pass piston through carry handle nut.

<li>Install gas tube w/o pin, repeat. Yes, your tube is slightly bent, but

<li>install pin and repeat

</ul>

This should isolate, by testing each part one at a time.


I have an old piston ground down slightly with a handle welded to it. I use this to push piston and make sure it travels freely before installing gas plug. I've found it useful to do every time, because it takes 10 seconds. Having failed to do it sometimes, I end up wasting a range trip for testfire, only to find the piston binding during live-fire.

I put this upper on my STG58 lower and it still does the same exact thing, so it's not anything with the L1A1 lower.

Trypcil
July 26, 2017, 22:11
Its starting to sound like a candidate for a gas hole enlargement! Anyone ???

Conagher
July 26, 2017, 22:19
Is the piston the correct length? I don't know what the correct length is, perhaps a DSA piston (which runs in my L1A1) might work better?

It's the correct length as it sits flush with the hole in the receiver for the gas piston.

http://i.imgur.com/dHoaZhzh.jpg?1

Here it is with the L1A1 lower after shooting the one round in the chamber;

http://i.imgur.com/OqjxZ1Nh.jpg?1

Here it is with my STG58 lower after shooting the one round in the chamber;

http://i.imgur.com/VokfTtrh.jpg?1

Here is the gas piston and spring just sitting in it's spot;

http://i.imgur.com/RbOb2Lth.jpg?1

I can cycle the charging handle and have it move the bolt and carrier all the way back and that all feels normal and correct.

Conagher
July 26, 2017, 22:29
Here is the gas plug sitting in its spot. It does wiggle around a little bit, is that normal?

http://i.imgur.com/QYq9GmHh.jpg

pl521
July 26, 2017, 22:56
Doug - I sold you the L1A1 kit. I want to help get your SLR running. I have a spare L1A1 gas block and gas plug I can send if you want to change them out. PM me and let me know.

Vulcanator
July 26, 2017, 23:10
Is the chamber clean? Perhaps a polish might help with extraction.

Conagher
July 27, 2017, 00:01
Doug - I sold you the L1A1 kit. I want to help get your SLR running. I have a spare L1A1 gas block and gas plug I can send if you want to change them out. PM me and let me know.

I already purchased another gas block just in case, but let me get this barrel timed better first to see if that fixes the cycling issue.

Conagher
July 27, 2017, 00:07
Is the chamber clean? Perhaps a polish might help with extraction.

The chamber is clean besides just the few rounds I've been shooting to troubleshoot the cycling issue. The cases are not hanging up in the chamber at all.

Conagher
July 27, 2017, 00:20
I've decided to re-check the barrel timing to the receiver as the gas piston will not just freely fall down through the gas tube each and every time. Even though my timing rods look to be parallel, I think I might have my receiver over-timed just a smidge too much. That will cause the gas piston to bind in the gas tube.

http://i.imgur.com/bPl0Sabh.jpg

http://i.imgur.com/Jch2QXah.jpg

the gman
July 27, 2017, 18:01
Firstly, I'd dump all the non issue parts like the gas piston and hammer etc; to HELL with 922(r).:whistling:

Secondly and most importantly, everything is pointing to a lack of gas pressure at the piston face. You have spent all this time and effort without (unless I missed it) measuring the gas port diameter. You need to remember these rifles and parts were built over 50 years ago and have had unknown numbers of rounds through them. You're now cobbling together pieces and parts from one set of worn parts to another and praying it will all work together.

Measure the gas port and report back as to size but it is my bet that you'll need to enlarge it somewhat to make it run well. :biggrin:

Edited to add; if you need/want/desire new parts to fix what you're having issues with, LMK at thegman1763@gmail.com and for the price of postage, you can have them to include NOS gas plug and gas tube. I'm betting its the gas port diameter tho...

Danielsand
July 27, 2017, 21:02
Firstly, I'd dump all the non issue parts like the gas piston and hammer etc; to HELL with 922(r).:whistling:

Secondly and most importantly, everything is pointing to a lack of gas pressure at the piston face. You have spent all this time and effort without (unless I missed it) measuring the gas port diameter. You need to remember these rifles and parts were built over 50 years ago and have had unknown numbers of rounds through them. You're now cobbling together pieces and parts from one set of worn parts to another and praying it will all work together.

Measure the gas port and report back as to size but it is my bet that you'll need to enlarge it somewhat to make it run well. :biggrin:

Edited to add; if you need/want/desire new parts to fix what you're having issues with, LMK at thegman1763@gmail.com and for the price of postage, you can have them to include NOS gas plug and gas tube. I'm betting its the gas port diameter tho...


This!

Gas operated weapons NEED the right amount of gas to function. If it short strokes,.....it needs MORE gas. Simple. Open up the gas port completely, and fire ONE shot. If it doesn't cycle,........enlarge the hole! Hole might be too small, too dirty, full of gunk......who knows. But,......the gas operated weapon WILL cycle given the right amount of gas (if you eliminated bolt/carrier drag, twisted receiver, screwed up recoil springs, weak ammo etc.).

Your piston is simply not getting slapped enough.

Trypcil
July 27, 2017, 21:34
So yes a consensus is forming - drill the gas hole(gas port). You will need some drills and a peice of 1/4" dowell(18ish") down the barrel so you know when to stop. A pillar drill is preferred but you can do it with a hand held electric!
http://www.falfiles.com/forums/showthread.php?t=355369
I had this same issue with a Brit, she had more gas than yours and I drilled out to #32 IIRC - moving up in drill size incrementally, keep it lubed, a bust drill can be a chore to remove. Good luck.

Conagher
July 28, 2017, 00:25
Firstly, I'd dump all the non issue parts like the gas piston and hammer etc; to HELL with 922(r).:whistling:

Secondly and most importantly, everything is pointing to a lack of gas pressure at the piston face. You have spent all this time and effort without (unless I missed it) measuring the gas port diameter. You need to remember these rifles and parts were built over 50 years ago and have had unknown numbers of rounds through them. You're now cobbling together pieces and parts from one set of worn parts to another and praying it will all work together.

Measure the gas port and report back as to size but it is my bet that you'll need to enlarge it somewhat to make it run well. :biggrin:

Edited to add; if you need/want/desire new parts to fix what you're having issues with, LMK at thegman1763@gmail.com and for the price of postage, you can have them to include NOS gas plug and gas tube. I'm betting its the gas port diameter tho...

gman,

Email just sent your way.

The gas port hole seems to be just right over 7/64" for the gas block bottom and top holes, but the barrel gas port hole is right around .110" in diameter.

I'm wondering if there's something wrong with my recoil springs? They look fine, but this L1A1 seems to need more hand pressure on the charging handle to pull the bolt/carrier back when compared to my STG58. I can just tell that the L1A1 recoil springs seem to be a little bit stiffer.

I looked at my black Maranyl buttstock and it had the recoil spring assembly in it, so I swapped them around to rule that out as being an issue.

the gman
July 28, 2017, 10:33
gman,

Email just sent your way.

The gas port hole seems to be just right over 7/64" for the gas block bottom and top holes, but the barrel gas port hole is right around .110" in diameter.

I'm wondering if there's something wrong with my recoil springs? They look fine, but this L1A1 seems to need more hand pressure on the charging handle to pull the bolt/carrier back when compared to my STG58. I can just tell that the L1A1 recoil springs seem to be a little bit stiffer.

I looked at my black Maranyl buttstock and it had the recoil spring assembly in it, so I swapped them around to rule that out as being an issue.

I'll respond to your email in a few but in the meantime, read this thread and especially the comments from GP as I think a light bulb might go off for you as to the problems you are having:
http://www.falfiles.com/forums/showthread.php?t=412126&highlight=gas+port+diameter

I really doubt your return springs are the problem; presuming they are standard issue and not some screwed up aftermarket crap (which actually tend to be weaker, not stronger than issue) they were designed and manufactured to function with the rifle as a system. You already swapped lowers to a metric which had the same issues on the inch rifle but works just great on your metric. You could also swap the lowers (actually, they are more correctly called the Trigger Mechanism Housing or TMH) from the inch to the metric and test fire. I'm willing to bet the inch TMH on the metric rifle will function just peachy because the issue is the lack of gas to the piston.

Seriously, 2 minutes with a hand held drill and the right size bit will cure all your ills and that includes the time to clamp the barrel in the vice and insert the dowel rod into the barrel. :biggrin:

OLDMANPBK
July 28, 2017, 11:24
Great read, and quite entertaining. :) :beer:

Conagher
July 28, 2017, 18:23
I had to go up to my family's ranch and use my Dad's drill index that has inch measurements. My gas port hole in the barrel is currently .104. What size should I start out with to enlarge it enough that it will run with the regulator on "4"?

Thanks,

Doug

Conagher
July 28, 2017, 22:42
I drilled the gas port hole out from .108 to .116 #32 and I had the gas regulator closed set on "0".

It did try to eject one spent cartridge (out of the 8 rds I shot) and was almost successful in that.

Did I get a crappy barrel with the kit I bought?



So what are people's suggestions on what to do next?

Trypcil
July 29, 2017, 22:42
Drill again -#31, then 1/8th - if its trying, that would suggest you going in the right direction, surely?

Conagher
July 30, 2017, 22:28
Drill again -#31, then 1/8th - if its trying, that would suggest you going in the right direction, surely?

Gunplumber said that if a 21" barrel won't run properly on setting 4 that there is definitely something seriously wrong. I drilled it out to .116" and it still won't run, and I have reservations about drilling it out bigger.

gunplumber
July 31, 2017, 07:59
Gunplumber said that if a 21" barrel won't run properly on setting 4 after drilling it out to .116 that there is definitely something seriously wrong. I drilled it out to .116" and it still won't run, and I have reservations about drilling it out bigger.

FIFY.

We're missing something significant.

msnyder
July 31, 2017, 10:21
Gunplumber said that if a 21" barrel won't run properly on setting 4 that there is definitely something seriously wrong. I drilled it out to .116" and it still won't run, and I have reservations about drilling it out bigger.

Sounds like you might be losing gas pressure. I would try a different gas piston and tube to rule those out. Make sure the threads of the new gas tube aren't cracked.

Conagher
July 31, 2017, 11:20
I have a different gas block, NOS gas tube and plug coming. I will be swapping those on to the rifle before doing anything else.

Conagher
August 04, 2017, 00:49
The gas tube that gman sent me is only 9" length, and my current gas tube is 9 1/8". This other tube is not long enough to let the gas nut thread all the way into the receiver before it comes out of the end of the gas tube. Now I need a proper length gas tube again.

gunplumber
August 04, 2017, 06:16
The gas tube that gman sent me is only 9" length, and my current gas tube is 9 1/8". This other tube is not long enough to let the gas nut thread all the way into the receiver before it comes out of the end of the gas tube. Now I need a proper length gas tube again.

Short tube that looks like L1A1 is usually Indian.

Ronin6.8
August 04, 2017, 06:26
Is that a DSArms gas tube that the gman sent you?
I order a DSArms gas nut and it longer, at least 1/8"

Ronin6.8
August 04, 2017, 06:37
I think that I'd call them and ask if that's the norm on there gas nut before I spent $25 bucks on one, they seem to make there chit up as they go

Conagher
August 04, 2017, 14:15
Short tube that looks like L1A1 is usually Indian.

That must be the case as it's too short to use on this Brit.

Gman said it was NOS but it's a used gas tube, that is only 9" long.

Conagher
August 19, 2017, 23:33
A new gas regulator, a different front sight gas block, a L1A1 gas tube, and now it will cycle more than 1 round at a time. I started out with the gas setting on 4 and it shot 3 rounds before it failed to totally eject the spent round while trying to feed the next round at the same time.

It did this a few times when I was testing it after getting it back together. Does it need more gas to make it run like a Swiss watch and not have any more cycling issues?

MAINER
August 20, 2017, 09:47
A new gas regulator, a different front sight gas block, a L1A1 gas tube, and now it will cycle more than 1 round at a time. I started out with the gas setting on 4 and it shot 3 rounds before it failed to totally eject the spent round while trying to feed the next round at the same time.

It did this a few times when I was testing it after getting it back together. Does it need more gas to make it run like a Swiss watch and not have any more cycling issues?

It would seem so, but it shouldn't, with a Barrel Gas Port of .116". Sounds like it is starting to run and may benefit from a few dozen rounds being fired to help 'breaking in", but I would drop down to a Regulator setting of 2 or 0 to get it to run as well as possible.


I'm wondering about the under side of the Feed Rails on the Receiver, are they rough, getting longitudinal scratches on the cases?
My DSA Receivers have all benefitted greatly from smoothing sharp edges in this area.
Still, that wouldn't explain a failure to extract a fired case.

Just a couple thoughts from an idle mind. :tongue: