Need some advise on Israeli FAL

[Jeff R]

I need some advise in regards to an Israeli FAL that me and my friends are building. My barrel over rotates about 12 degrees from top dead center when screwed in to the receiver. My friends and I thought that a barrel washer would solve this problem. If this is the solution, can anyone tell me how thick the barrel washer should be? If there is a better way, I am all ears. Thanks in advance for your help.

[W.E.G.]

Assuming that nobody has previously messed with the barrel shoulder, and your barrel over-rotates that much, you may have an inch-pattern barrel.

If indeed you do have an inch barrel, you need to back off the barrel a FULL REVOLUTION, and use a breeching washer of a thickness of around 0.070"

Better to order one that is a bit too thick and make it thinner as needed.
See http://gunthings.com/inchupper.htm

For the purposes of calculation, remember that one full revolution of the barrel is 0.062"

[Jeff R]

Gary, Thank you for your help, I really appreciate it.

[W.E.G.]

Good luck with your build.

[Haze]

Hi Gary. I'm one of the guys helping Jeff with his build. The barrel is definitely an Israeli HB, so would the same advice apply? If we install a washer, what will that do to the headspace? Thanks for your help.

[W.E.G.]

If you are sure its an Izzy HB, it should time early (instead of late) and you shouldn't need a breeching washer unless somebody monkeyed with the barrel shoulder before you got it.

Starting to sound like somebody already monkeyed with that barrel.

Most likely, you are now in the situation where you need to use a very thin breeching washer (thickness of a beer can), or you could remove 0.063" from the shoulder in order to use a conventional-thickness breeching washer.

And you could peen the shoulder of the barrel. I don't know how good your peener is. Depends on how much experience you got whackin'. Most folks say it aint good for you. Consider other options.

[rynich]

Izzy barrels have a different thread pitch intirely. If you have the Gunplumbers book he goes into detail on it. The breeching washer will change you head space, if you want to know how to get a very close measurement for the breeching washer.
Back it off just as Gary stated, use you alignment tools then measure the gap between the reciver face and the barrel shoulder this should get you close. It is also acceptable to have a small space between the feed ramps and the barrel face, the larger this gap the larger the Locking shoulder.
This is how I have done all my Inch builds and I have never had a problem, Inch breeching washers come in numbered sizes. I don't have any reference material, to give exact measurements with me or I would post them for you.
If you need it know then you can make a breeching washer out of a 1" your local hardware store, just shape it and hand sand it to spec.

[shortround]

First, what you need is a shim, not a barrel washer. You start putting washers in a metric barrel (adding one full turn) and you end up with abnormally long headspace that can't be corrected.

You need to get the barrel to hand tighten at the 10:30 to 11:00 position. The way I read your post is that it hand tightens to just past TDC? If you are 12 degrees past TDC, then you need ~.002" to get you to TDC and another .008" to get to 10:30 (45 degrees BTDC) or so. Call or email gunthings.com to see if they have a .010" shim. I just bought one from them, which I didn't use. If they don't have one, email me and I'll sell you mine for what I paid. Or, you can get some .010" stock and make one.

An alternate method (though crude), like Gary says is to lightly peen the shoulder all the way around enough to displace metal so that it tightens. Just becareful playing with that peener.

[Haze]

Thanks guys. I think we'll try the shim.

[owlcreekok]

I am in process with the exact same thing. I bought an Izzy HB that had been put together in a very scary way. Nuff sed there. I have two 0.010 shims from Gunthings. I will be thinning them with emory paper to acheive the timing I need. Mine overtimes to 2:30, IIRC. When at 12 o clock I measure an average of 0.016" around the shoulder-receiver gap. (feeler gages) Putting both shims (0.020") on it and cranking it down by hand, as hard as I can get it, (weak peener?) it looks like about 10:30.

Been too busy to get serious on this. Let us know how ya come out, Haze. I'll do the same. Might even get lucky and swap some Locking Shoulders. (Fat chance of the numbers hitting, eh?)

[rynich]

Shortround,
What is the difference between a barrel washer and a shim. Not being a smarta$$ I just thought they were one in the same.

[Jeff R]

Gentleman, Thank you all for your advise. Sounds like we have some possible solutions to out problem. I am looking forward to my newest FAL!!

[tac-40]

Barrel washers are thick and look very similar to a standard washer you would use with nuts and bolts. The shims are very thin and flexible and are often measured in the thousandth or ten thousandths of an inch thickness.

As a comparison, take a look at a set of feeler gauges. The really thin ones are shims and the thick ones are washers. They look the same but have diferent names.

[rynich]

Thanks