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JeepsAndGuns
February 05, 2009, 20:04
So I a little mad.

I got a brand new chrome lined barrel from sarco, and I test fit it on my DSA reciever. The hand time is off. About 10. I try the sanding disc, and after about a half a hour of sanding and testing. It did not move one bit. Not even a hair. So I get fed up and take it to a local gunsmith to have a touch taken off the sholder. This guy works mainly bolt guns, but he came reccomended by a couple diffrent shops. Pretty much the only guy who's name is said when I ask about good gunmiths in the area.
I go to his shop, show and tell him what I have and where it needs to hand time too. I leave the barrel and reciever there with him.

I go and pick it up and well, long story short, he shaved too much off of it. He timed it to just a few hairs short of 12. I told him he took too much off, but he swears it will be fine, it about a thou crush fit....blah blah, "you would be suprized how much it will take to tighten it up" blah blah. He had that I am the expert not you, type of explaining it to me. I tried showing him agan where it needed to be, and he kept going back to where he has it is correct. I know I will not be able to convince him otherwise, and I also know I will not get my barrel and reciever back unless I pay him. So I decide to cut my loss, pay him his $75 and leave.


So once I get home I screw it back on and work it tight and loose a couple times to test the hand time, and I can take and hold it with a firm grip and bring it all the way to 12 with a stiff twist, mabey even a hair past 12, with my hands.

I remember reading on here that there are washers made for barrels that are over timed. Can someone school me on them? Where can I get them, are there diffrent thicknesses, or is there a one size fits all that you have to shave to fit your specific needs. And how thick of one do I need?

Thanks.

hanko
February 05, 2009, 20:26
Gunparts guy had ( may still have ) shim washers...they're used to shima grinding wheel on its arbor. Start with 0.005" per 30deg. (1 point on the clock).

-hanko

USMC 0341
February 05, 2009, 20:29
Yup, all inch FAL's are designed to be built using shim washers so this fix is not just some do-it-yourself, garage fix.

FAL guy
February 05, 2009, 21:37
Originally posted by JeepsAndGuns
I I try the sanding disc, and after about a half a hour of sanding and testing. It did not move one bit. Not even a hair.

If the timing did not move after 30 minutes of sanding and testing something was amiss. It is quite possible the breachface was contacting the inside of the receiver rendering your continued sanding futile. Then if the GS relieved the breech face a bit, the barrel would time to the point you had sanded it to.

Just a thought.

English Mike
February 05, 2009, 21:48
Originally posted by FAL guy


If the timing did not move after 30 minutes of sanding and testing something was amiss. It is quite possible the breachface was contacting the inside of the receiver rendering your continued sanding futile. Then if the GS relieved the breech face a bit, the barrel would time to the point you had sanded it to.

Just a thought.

Highly unlikely with the thickness of a sanding disk between the receiver face & the barrel shoulder.

Court in Fl
February 06, 2009, 02:27
In the past I have made my own washers from a Coke can and they worked fine.
Cut out a piece of can and find a socket that is about .950 in dia. and use it to trace a circle on the aluminum, cut out the circle with a Xacto knife.

Thread the aluminum onto the barrel and install & time the barrel with red locktite.
Make sure you get it right.
Then run the Xacto knife around the barrel shoulder till the oversive aluminum just falls away.

The handguard ring should cover up the .005 shim.

Good Luck, Court in FL.

L Haney
February 06, 2009, 08:54
I was recently working with my bud on some galil builds and several of the barrels were over timed. We have access to SS shim stock from about .002 and up. We also did one with the coke can shim method. One lesson I learned from this. The soft aluminum will "flow" as more torque is applied. If your center hole is smooth, with no radial flaws (gashes) the shim will stay under the barrel shoulder and crush to fit. If it is flawed in the center cutout, it will split and creep out from under the shoulder from at least one place. A fairly easy way to cut the center hole is with a piece of tubing or pipe (thin wall) of the proper size sharpened to make a punch. I bevel the inside with a half round file and smooth the outside with emery cloth. Place the shim material on the end grain of a scrap of hardwood, and give it a firm tap with a medium sized hammer. If you did a good job of beveling/sharpening the tube, you'll have a smooth lovely center hole in your shim. Hope this helps.

Lowell

vmtz
February 06, 2009, 09:19
As CE would say "just peen it! Stupido-fuckero!"

Fr. Vince

ggiilliiee
February 06, 2009, 10:01
sometimes i just use a washer made out of human flesh dried in the sun ....FYI a tattoo will add .ooo5 to the washer (just for reference) ..heheheh

never peen ...never use coke cans .....always pepsi .....

JeepsAndGuns
February 06, 2009, 11:03
Originally posted by FAL guy


If the timing did not move after 30 minutes of sanding and testing something was amiss. It is quite possible the breachface was contacting the inside of the receiver rendering your continued sanding futile. Then if the GS relieved the breech face a bit, the barrel would time to the point you had sanded it to.

Just a thought.

Nope, even screwed all the way in right now, I can still see a slight gap. No metal was taken off the breech face, only the barrel sholder.

I will fool around with some coke cans and see how it works.

johnny.308
February 06, 2009, 11:45
The breech face not the receiver face. It is located at the end of the hole that the barrel screws into. Perhaps the barrel is bottoming out there before the shoulder gets to the front of the receiver.

bykerhd
February 06, 2009, 12:25
It's too bad your "gunsmith" was so clueless about FALs.
A slight gap between the barrel's breech face and the ramps inside the receiver is fine. There should NOT be any gap between the barrel SHOULDER and the front end of the receiver when the barrel is tightened.

Breeching washers are available for Inch guns which could be used to correct a major issue. It's hard to believe that your guy would remove THAT much metal.
If he did, you are beyond the average home remedy and need someone with a lathe to re-cut the barrel shoulder.
There are several experienced FAL smiths around here that could do that. Probably at reasonable cost.

Try the aluminum can thing and see where you end up.
It's your least expensive option right now.

Right Side Up
February 06, 2009, 13:16
My opinion is that if it needs a barrel shim the shim needs to be a lot thicker than .002".

I had to shim a barrel one time, and I used a .015" thick valve spring shim for a small block Chevy. The part number is C203HP. HP means it heat treated harder than a rock. I trimmed the barrel to get the timing right with that shim and torqued it down. Hasn't moved. The C203HP shim is perfectly flat because it is surface ground.

IMO, a coke can isn't near good enough metal to be using for a barrel shim. You need some real good stuff there.

You don't HAVE to go to a gunsmith to get your barrel trimmed for the shim. Any good machinist with a lathe can do it.

erhauser
February 06, 2009, 15:27
Gunthings.com, last time I checked, sells thin (that is a few thousands of an inch) breaching washers. Before I saw their supply I made my own. I purchased from McMaster Carr, 1" id shimming washers (they are availible in many thicknesses, and a number of matals) and cut the OD down to the proper size using an inch breeching washer as a guide.

It works fine, and since simple calculation using the known thread pitch, will yield how much thickness is required for a desired "o'clock" adjustment, the purchase of a couple of thickness and trial to verify the appropriate thickness is well within the skills of an average home gunsmith.

Cofaler
February 06, 2009, 19:18
Go here: http://estore.websitepros.com/832529/Detail.bok?no=801. I don't have a lathe so I built my own barrel turning jig out of a piece or 1/4" all-thread, a .308 case, a .243 case, a couple 1/4" nuts and a drill. The barrel is captured around the all-thread by the .308 dase, (in the chamber) a .243 case (at the muzzle). The primer pockets of both cases were drilled out to allow the all-thread to pass through. I've used it several times and it works great, I use a tri-angle file with a 'safe' corner ground into it so the file will only take material from the shoulder and not file a groove into the barrel which could weaken it. I know it sounds crude, but it works well. It's controllable, takes an even amount of material around the seating area of the barrel, and makes a nice, clean surface if you're careful and take your time. I'll try to get a picture of it if you want a visual.

JeepsAndGuns
February 06, 2009, 20:15
Ok, fooled around with a coke can and the thickness of the can brings the timing back to perfect. I measured the can and it was .005 thick. I just had a member PM me who has one. So I should be able to get this all fixed up now.

Thanks for all the help!

L Haney
February 07, 2009, 13:54
Originally posted by Right Side Up


IMO, a coke can isn't near good enough metal to be using for a barrel shim. You need some real good stuff there.



'Splain that to me please. Not trying to pick a fight, just wondering how you came to be of that opinion. Maybe I'll learn something. Happened before.

Lowell

ggiilliiee
February 07, 2009, 14:19
cofaler ..i think i just had an annurism ...combined with just a touch of anal leakage ....hehe .

http://community-1.webtv.net/ggiilliiee/shaver/


can you shave and signal aircraft with the finish ????he
serously .pretty ingenious set up ..but ohhhhh the suffering ...:bow:

L Haney
February 07, 2009, 15:23
ggiilliiee, he's doing the same thing I've had to do for years. He figured out a way to get the job done. Yeah, it's a pain, but we ain't all got access to machine tools. Sometimes, good enough IS good enough. Dammit. Why don't we get some pork added to that bill in congress for a lathe for everybody that wants one? Wouldn't make a dent in the total. :)

Lowell

ce
February 07, 2009, 15:56
To peen, or not to peen, that is the question.

Whether 'tis nobler to hammer precisely or to suffer the slings and arrows of outrageous ineptitude.

Nay, I say, take this gunsmith to a nunnery, and teach him the pronouncement of his fubbery, with a bit of rubbery buggery, he deserves not death until he has paid his penance. The Sisters of the Silent Scream have a table awaiting.

If only Lord Ggiillliie would take the sacred ball peener, and move the mountain to the metal, he would lie in wonder every night, at his starry eyed success of bringing the threads together boldly.

Cofaler
February 07, 2009, 17:02
Actually I don't consider it a pain at all. To check progress all I have to do is unchuck it from the drill, I can leave my all-thread and brass rig in the barrel when I screw it into the receiver to check timing. It's fast and although I've never tried to signal aircraft with it (they make better tools for that), it's a very effective method of turning down the barrel shoulder and I've got about 10 minutes and not a penny in it. As far as finish, I am very pleased with the results and can see no functional difference between doing it my way and turning it on a lathe.

As far as ggiilliiee's gizmo, it looks like it would be slow but it would work. Using my system saved me $30.00+shipping, although I'm sure Ggiilliiee could use the money for English lessons. Maybe Gun Plumber would help him out....

Ggiilliiee, if you came up with that all by yourself maybe that brain of yours works better that your idiotic babbling would lead us to believe. On second thought, I've read too many of your moronic ramblings to hold out much hope.

L Haney and I will keep doing it our way until we get our bailout lathes. :fal:

Cozmacozmy
February 08, 2009, 01:41
Cofaler, I would like to see a pic of your setup.

Cofaler
February 08, 2009, 09:33
PM me your email address and I'll send some to you. The 'files won't allow me to post attachments for some reason.

4895SHOOTER
February 08, 2009, 11:46
I'd like to see this marvel of ingenuityas well, please! Try Photobucket. Just for the info, hard, steel stock will act as an unyielding shim, aluminum will act as a "crush washer"; which means that there will be a final torque at which, as mentioned before, it will start to flow and actually seal the area in question such as on the oil drain bolt on the BMW motorcycle. If the final crush torque is high enough, theoreticaly you could undertime a barrel and continue crushing until correct timing is reached - right?

ggiilliiee
February 08, 2009, 13:19
sometime thought are just ramblings too those who still play checkers .and are listening to someone who runs lathes with two chucks and 5 axis ......... ....how long it take is a matter of what kind of sandpaper .....only took 10 back n forth strokes with 400 grt to remove .oo1 from that one in the pic ..dead nuts on the depth ....go fugure ...
actually if ya added a few more items youd have the barrel testing equipment weve had at shops for nye on ta 30 year now ......hehehe ..some day ill show ya a picture of te REAL device ... ..would make a nice change over cutting and putting barrels on offline .....as you are now ....(why is my gun shooting 3 feeet off at 25 yds ...hehe n...
the moral of the ramble ...id rather ramble than not get it at all .ehhehe ...
ive always felt its "others" who are the true FALIC symbols on the site . ....hehehehe..some folks just take a learning experience as an "insult".......those are the guys who will buy sticks ....and then post ..why is my barrel not lined up . .... ....:wink:

PS

http://community-1.webtv.net/ggiilliiee/BARRELTIMINGTOOL/

bet if your gunSMURF ...woulda let go of the gig is rambling ...i dont understand simple concepts ...so he must be wrong

...ill use sticks to line up the barrel ...we wouldnt be posting rite now ,wouldeth we matey ......heheheheh ..having fun yet ??????
.also .......dirt levees dont hold bak water ..ill get into that later ...when your rested ...hehehe ..i can post you picture with my 100 year old web tv too if ya like ....

Cofaler
February 08, 2009, 15:52
.308 case in the chamber, .243 case in the muzzle prevents damage to the crown. Electrical tape on all-thread prevents steel contacting rifling. The nuts really don't have to be tight at all, just a bit past hand tight is fine.

<a href="http://s224.photobucket.com/albums/dd296/Cofaler/?action=view&current=DSC03509.jpg" target="_blank"><img src="http://i224.photobucket.com/albums/dd296/Cofaler/DSC03509.jpg" border="0" alt="Filing down barrel shoulder"></a>

Use slow speed on the drill.

<a href="http://s224.photobucket.com/albums/dd296/Cofaler/?action=view&current=DSC03513.jpg" target="_blank"><img src="http://i224.photobucket.com/albums/dd296/Cofaler/DSC03513.jpg" border="0" alt="Filing down barrel shoulder"></a>

The brass fitting in the vice helps stabilize the other end of the all-thread and still allows it to turn.

<a href="http://s224.photobucket.com/albums/dd296/Cofaler/?action=view&current=DSC03512.jpg" target="_blank"><img src="http://i224.photobucket.com/albums/dd296/Cofaler/DSC03512.jpg" border="0" alt="Filing down barrel shoulder"></a>

Make sure you grind a 'safe' corner on the file so it won't cut a groove into the barrel. I prefer using a triangular file because it allows you to get deeper into the shoulder than the external diameter of the barrel threads will allow a larger file or something that slips over the threads.

<a href="http://s224.photobucket.com/albums/dd296/Cofaler/?action=view&current=DSC03514.jpg" target="_blank"><img src="http://i224.photobucket.com/albums/dd296/Cofaler/DSC03514.jpg" border="0" alt="Filing down barrel shoulder"></a>

Be careful to keep the file square, go slow and check progress often. I did two rifles last weekend with this settup. I centered the rear sights in the lower on both rifles. One nailed the 100yd gong on the first shot and required 3 clicks to the left to get it right on. The other one was about 6 clicks off. I'm sure this is a timing issue, as we just "eyeballed" the barrel timing as we tightened. Both rifles gave about 3" at a hundred yards with SA surpus and iron sights. I'm happy with both of them.

Right Side Up
February 08, 2009, 17:10
Originally posted by L Haney


'Splain that to me please. Not trying to pick a fight, just wondering how you came to be of that opinion. Maybe I'll learn something. Happened before.

Lowell

Hey no problem. Aluminum is too soft for the application. It will crush when torqued and not load the barrel threads sufficiently.

The shim should be made from heat treated steel. The C203HP valve spring shim I mentioned is commonly available and works great. It's made out of high quality steel and is heat treated so it won't crush.

Proper torque on he barrel is very important.

USMC 0341
February 08, 2009, 22:09
Cofaler,

I had assumed you chucked the drill to the muzzle end. That way, when it's time to check your progress, not only do you not need to un-chuck but you can use the drill to spin the barrel into the receiver.

Another tip I meant to mention - either tape or just hold a flat object (something like a tongue depresser) to the working face of the file in the vertical direction. This gives you a better feel for the "squareness" of the file to the face of the object.

Cozmacozmy
February 09, 2009, 02:19
Looks nice Cofaler, wescog at it best.

FalFNatic
February 27, 2009, 13:36
Originally posted by Court in Fl
In the past I have made my own washers from a Coke can and they worked fine.


Doesn't the aluminum and steel cause electrolysis? I have always found that it always does when using steel screws in aluminum.

ggiilliiee
February 27, 2009, 14:24
hope ya got a good drill ..the bounce in the chuck will be transmitted to the datum by the rotation if your not rigid as a milling machine .......005 out on the chuck ..005 out on the shoulder ...(put a hardened pin in the chuck rigidize it and put a dial on the pin and spin the drill ... ..thats how far off line youll end up with ...and at the end of the trig legg even worse ....throw a depth mike on the shoulder after the work ....might surprise ...surprise ...surprise .....ya ...