I did some headspacing on my FAL's this weekend to get them ready to test fire.
I borrowed some shoulder locking gauges from Illya (thanks for the help my man!) I got 2 out of my 3 FAL headspaced. The third one I'm having an issue with.
With the shoulder locking guage of .253 in the receiver I put in my go guage and the bolt doesn't close.
Then put in my nogo gauge and the bolt doesn't close.
This is how it is with all the shoulder guages. Without the go or nogo guages in the bolt closes flush.
What am I missing? What are my options? I don't think locking shoulders go below .253 do they?
If your go guage does not close than there is no way your no-go will close. Have you tried a live round yet (using safe handling). If a actual round will fit you should be good to go.
I did a FAL build years ago before it was easy to get all of the different locking shoulders. Mine was too tight also, so I cut a diamond hone down to the width of the locking shoulder/bolt contact area and used it to cut down the surface the 5-6 thousands I needed to get the bolt to completely close on the go. It was a pain in the ass as the locking shoulders are quite tough. I have read where others used a surface grinder to do the same thing.
Gun Parts Guy can custom grind locking shoulders, once you know the dimension. Guess how I know this.
Having a set of Fraction,Number and Letter drills helped, using the shanks to rough out the size estimate. Had to procure some undersize gauging pins,from Grizzly, to get in the ballpark.
redchevyman is correct about if it won't close on a go gauge then there is no way it will close on a no go gauge, however, I would not just go by it closing on a round.
Which brand of receiver on you using? The last few DSA's that I have built on needed smaller locking shoulders. One required a .253 and one was actually a .251. If you have any drill bits that the shank diameter is smaller than a .253 thry those with the gages and see what the results are.
I am assuming you do have the extractor removed from the bolt while you are doing the headspacing with the gages.
redchevyman is correct about if it won't close on a go gauge then there is no way it will close on a no go gauge, however, I would not just go by it closing on a round.
Which brand of receiver on you using? The last few DSA's that I have built on needed smaller locking shoulders. One required a .253 and one was actually a .251. If you have any drill bits that the shank diameter is smaller than a .253 thry those with the gages and see what the results are.
I am assuming you do have the extractor removed from the bolt while you are doing the headspacing with the gages.
The receiver is a Dan Coonan. I'll try a live round this weekend and see how that goes. The drill bit idea is a good one I hadn't thought of that. I'll see how that does and post the results.
Hello Gunco
Your chamber is too short. It sounds like you might be missing the barrel shim that goes between the threaded part of barrel to receiver end, or cutted the barrel to index the barrel for 12 oclock torqued. If you can get a barrel shim and get the barrel rotated out one complete turns out, creating a longer chamber, that will help the the too short of chamber. Keep in mind that most FALs don't use barrel shims but sometimes mismatching barrels or receivers and parts or brands to assemble a complete rifle, you just need shimming or trimming. Keep us posted the repair results. IRONMULE
I was worried I would need to shim the barrel but when I built it the barrel was hand tight to the receiver at the 10-11 oclock then tighten to 12 oclock with a barrel wrench. So I assumed this barrel did not need any shimming.
One of my other fals needed shimming and it headspaced perfect at .266
I think I will try the live round trick first. then the small shoulder gauges using drill bits, then last resort would be barrel shim.
I was helping Gunco with this build and that barrel fit like it belonged to that receiver. All the other FALs we built that day all needed something done to make the barrels fit, but that one was the easyst to build.
When he called me and told me the issue I was like WTF. Guess that goes to show you the easyst build might be that hardest.
Nice looking rifle by the way. I built one real similar to it earlier this year on a DCI receiver also, except I went for the 50.63 look with a folding charging handle, 18 inch barrel, and holland style rear sight.
check your chamber for any fowling sand dirt etc...and clean it really good then check the locking surface of the bolt (rear of your bolt) I had one that had a large burr (damaged) it was giving a false too tight HS reading.. never even thought about looking at the locking surface carefully before that happened.. B2B
I just headspaced mine this weekend on a DSA reciever with an Imbel barrel and it closed on a GO gage @ .252 with a Forster gage. This is with the chamber cleaned, gage cleaned, and bolt cleaned. I did have to sand the barrel shoulder to get the barrel to hand time to 1030. I will be ordering a .251 LS from GPG to have it work.
Before you go spending money, Does it close on the no-go gauge? Its supposed to close on a go gauge, but not a no-go or field. Or are you talking about a locking shoulder guage?
I tried some gauges all the way down to .247 and non closed on the go guage. So I did what a couple people suggested, I used a live round which closed easily on the .250
Just need to get a locking shoulder install it and take her to the range. Range time and report will be a few weeks.
You may want to hold up from putting a locking shoulder in right now and read this thread from the FALfiles on some of the latest DCI receivers and issues that where had with them before anything goes wrong with firing the rifle. I just now put two and two together and remembered this thread from earlier this year over there.
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