increasing headspace on newly installed factory original fixed shouldered barrel
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Accuracyman
Active Member
People have given some good advice on the proper way to setup a barrel swap. As others have stated you are dealing with several critical dimensions. Since you are screwing on a similar factory barrel I will skip the major diameter and threads. So lets discuss headspace and tenon length. The tenon length dictates the gap between the bolt and the barrel. Most factory barrels have a larger gap between the bolt and the end of the barrel than a custom barrel job. Most gunsmiths set this gap (on hunting type rifles) between .005" to .010". By screwing on a different barrel one must check this gap to make sure you haven't opened it up excessively. It is possible to close it up too much as well. I check every barrel in my shop with round thickness shims between the bolt and the barrel to make sure I have the correct space between the bolt and barrel. Once you know you are correct then on to headspace. The proper answer is the one RuninL8 gave by renting a reamer and slowing opening up the chamber headspace until the go gauge goes and the no-go doesn't.
I have been on the line with an experienced Benchrest shooter that swapped barrels between yardages and the case ruptured on his first shot. We found out the barrel he screwed on was from a different gun with a different tenon length causing excessive gap between the bolt and barrel leaving too much case exposed unsupported. He had brass blown in his face! I use this extreme example to point out the importance of making sure the barrel is indeed safe and all clearances checked.
Sorry for the novel but swapping a barrel can be dangerous if done incorrectly. Focusing on the headspace gets you part way there. Good luck and be safe....check everything....never assume.
You can make your own gap shims by cutting pieces off a set of feeler gauges and cutting them round.
This is written by an old guy that has seen just about everything that could go wrong.....go wrong.
I have been on the line with an experienced Benchrest shooter that swapped barrels between yardages and the case ruptured on his first shot. We found out the barrel he screwed on was from a different gun with a different tenon length causing excessive gap between the bolt and barrel leaving too much case exposed unsupported. He had brass blown in his face! I use this extreme example to point out the importance of making sure the barrel is indeed safe and all clearances checked.
Sorry for the novel but swapping a barrel can be dangerous if done incorrectly. Focusing on the headspace gets you part way there. Good luck and be safe....check everything....never assume.
You can make your own gap shims by cutting pieces off a set of feeler gauges and cutting them round.
This is written by an old guy that has seen just about everything that could go wrong.....go wrong.
About the thickness of a doublemint wrapper, peel the aluminum foil off and you have .002" foil shim and a .003" paper shim
Tolerance stacking, no way the face of the action, face of the shoulder and both faces of the shim are 100% parallel
If you really believe that, why are you asking?
Uh, no, they don't. Only rifles that have barrel nuts use barrel nuts.
xtratoy
Well-Known Member
in case you haven't seen them... https://northlandshooterssupply.com/prefit-barrels-2/criterion-barrels-remington-remage/
Theoritically, yes; do you think that shim will result in any more misalignment in the OP's rifle or 99.999% of the other factory produced rifles out there? I'm putting a lot more faith in the flatness of the shim.
Lenny Foffa
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For me, the barrel, the action and the bolt go to a proper gunsmith and get Blue printed, using proper gauges. No shims for me. Thank You!!
That is why I specified "actions that allow it"; I understand the OP can't do it but it is a common solution to this problem in rifles that can.
Darryle did give a valid reason against it, I don't think it applies in the OP's situation.
Let's say there is no saftey issue. Some other problems I see. If the gun is not stainless steel. The stainless shim will cause dissimilar metal corrosion. Had a guy bring me a blued R700 with stainless action screws. It was a nightmare getting those out and had to repair the screw holes on the action. The other is the shim will eventually become damaged with repetitive recoil. Have it corrected properly.
If this was a remington or rem clone. I have bought extra thick recoil lugs and milled them to correct this exact issue. No room for short cuts in rifle building.
If this was a remington or rem clone. I have bought extra thick recoil lugs and milled them to correct this exact issue. No room for short cuts in rifle building.
I agree with Darryle. If the thickness of the recoil used is a determining factor, it should be information that needs to be factored in. But that's just me.
I've seen them. Those don't even cone close to being "typical aftermarket barrels." A very small corner case, at best.
