Gunsmithing Barrel - Cut for a different action and rechamber?

[Dos_Meadowlandos]

My friend is getting out of a caliber and is selling off his barrel, brass, etc.

The barrel he has is a 6mm Creedmoor for an Impact 737 action. Is it possible to cut the action threads off and re-thread the barrel to an AI AT action and re-chamber it in 6mm Creedmoor?

If possible, any recommendations on an East Coast gunsmith that could do this for me?

 

[nksmfamjp]

Technically it is possible. Many folks say it turns out well….but every gunsmith I have talked to about this says it is a terrible idea. Not sure why??

 

[acudaowner]

all up to you it's your gun , what you liked , what you did not like problems or a step by step on how you had it done .might also show a range trip results .best of luck send in pics .

 

[matthias]

Lots of variables to consider . Just to start, contour of the barrel, number of rounds fired or condition of the bore, and cost of the labor.

All of these things add up to most people that pay to have barrels threaded and chambered just put new barrels on builds.

Many people don't like the idea of using a pre-owned barrel. Kinda like putting used tires on a vehicle. 90+-% things go just fine. Sometimes you are screwed through no fault of your own.

 

[Dos_Meadowlandos]

Thanks, @matthias. I understand the used tire analogy, was curious about the viability.

 

[matthias]

Personally I have done exactly what you are asking about. Taken a used but not abused barrel and rethreaded and chambered for a different setup. Worked well for me. I went from a 260 rem that was not performing well to a 6.5x55 that did very well. Seemed the extra speed is just what that barrel wanted.

 

[Baron23]

Thanks, @matthias. I understand the used tire analogy, was curious about the viability.

I think any competent rifle gunsmith should be able to set back the barrel (cut off the tenon and chamber portion) and rechamber/rethread.

As said, you may want to be careful of how much you are taking off, if the barrel contour has a shank and how all that will work out in the final configuration, and of course condition and remaining life in the barrel which is often difficult to determine.

 

[Rob01]

How many rounds does he have down the barrel? Setting it back, as long as contour allows, is not a problem. If shot out then usually you will not get a full barrel life out of a set back and maybe get 50-60% and probably why some smiths say not to but they might have their other reasons also. If you want to do it and being in CT get with Josh @bohem at Patriot Valley Arms in PA and see if he can do it.

 

[b6graham]

is the barrel new enough that it's worth the chamber cost? most guys who set back barrels do it themselves/friend or are BR nuts

probably better off just selling the used barrel and getting a brand new one honestly

 

[high right]

It's hard on Reamers

 

[Maurygold]

Lots of interesting opinions in here. I shot f class with guys that would set a barrel back 1-3 times and keep shooting it. So I’m very confused at those saying this isn’t a good idea

 

[matthias]

Lots of interesting opinions in here. I shot f class with guys that would set a barrel back 1-3 times and keep shooting it. So I’m very confused at those saying this isn’t a good idea

Its not that its a bad idea , I dont think so anyway. I think a decision needs to be weighed against all factors.

An f class competitor knows the history and origin of the barrel. Much easier to make that decision especially when the barrel shoots well

 

[b6graham]

Lots of interesting opinions in here. I shot f class with guys that would set a barrel back 1-3 times and keep shooting it. So I’m very confused at those saying this isn’t a good idea

extra long and straight barrel contours where the whole barrel is a shank basically. and the KD target crowd often get fixated on single barrels as if they're god. so they set them back versus 'risking' a new barrel

also round count per year

and again it depends if you're doing it yourself/friend where you dont have the $350 chamber cost

 

[hero's machine]

Don't forget you're at the mercy of the initial setup. If the first chamber is not nuts on....you're not going to chase it and have different results.

 

[FisherT&C]

You need 1.5" of threaded tenon for the AI after the original threads are cut off and then ideally a 1.20"+ shoulder after that.
I've done similar jobs. I had a 6 GT barrel a customer brought in with a chamber so crooked a full land ran up into the neck. I parted off the threads and blew out the old chamber with a drill, trued it up and rechambered. The barrel shot awesome after that, it was a Proof Comp so plenty of material to do it. The barrel was not originally chambered by Proof Research, just to be clear.

 

[matthias]

Don't forget you're at the mercy of the initial setup. If the first chamber is not nuts on....you're not going to chase it and have different results.

This is true to a point. Careful boring/drilling can reduce issues. I say can reduce issues because sometimes there is nothing to do but cut off the chamber/throat and start over if there is enough barrel.

 

[LRI]

FWIW:

We do setbacks, but I try to temper it with the cartridge, how the gun was used, and the mileage. Take a 22-250 running featherweight pills on prairie dogs, for instance. Likely the barrel will be smoked after 1000-1100 rounds. It's very possible to lop off the tennon and get up into fresh material as a gun like this will most likely have a fatty tube hanging off of it with plenty of cylinder. One might expect it to deliver another 1,000 or so rounds, but I've yet to see it. The theme seems to be about 1/3rd of where it died before.

Remember, Chamber temps can flash to over 6,000*F, and the pressures are ##,### digits. It's not unreasonable to think that the steel forward of the immediate throat is adversely affected by this. A situation where the person travels for competitive events/hunts is where a setback can start to resemble a roulette table.

As for the comment about accelerated tooling wear on a ream, I've not seen that. On its best day, a SS barrel made of 416 will hit maybe 42 Rockwell C scale. A cut-rifled barrel could be this hard, but most live in the low 30s. Button barrels are always on the soft side because you'll break the tool if you try to pull through the hard stuff.

I think you'd be hard-pressed to run a bolt gun hard enough to heat cycle it sufficiently and get any change to the chemistry that would alter the hardness. -Maybe if a guy went total "Blackwater" and tossed his shit in a lake afterward.

C.

 

[hero's machine]

Maybe if a guy went total "Blackwater" and toss his shit in a lake afterward.

C.

Probably the funniest thing I've envisioned today....you win the internet.

 

[Wannashootit]

As for the comment about accelerated tooling wear on a ream, I've not seen that. On its best day, a SS barrel made of 416 will hit maybe 42 Rockwell C scale. A cut-rifled barrel could be this hard, but most live in the low 30s. Button barrels are always on the soft side because you'll break the tool if you try to pull through the hard stuff.

Interesting. I'd always assumed that the button-rifling process would work-harden the steel in the grooves.

 

[FuhQ]

Lots of interesting opinions in here. I shot f class with guys that would set a barrel back 1-3 times and keep shooting it. So I’m very confused at those saying this isn’t a good idea

I've set barrels back, and never had any issues. I know lots of folks who have, too. Hell, I had one done exactly like what he's describing...It was a Rem 700 cut barrel, had the tenon cut off, and rethreaded for a Browning A-Bolt II. That rifle shoots 0.3xx" groups. So I have absolutely zero idea why any smith would tell someone that it would be a bad idea, or cause any negative affects, unless they were just trying to sell him a new blank, and start from scratch? Which is very possible...

 

[matthias]

Read through the responses. Quite a few situation dependent reasons

 

[Easy_E]

If your having one done make sure the old chamber is completely gone . I had a customer with a six creedmoor that was blowing the shoulder out because some of the 243 chamber was left behind . Had to move everything ahead two more threads and it still shoots great and no funky shoulder .

 

[LRI]

Interesting. I'd always assumed that the button-rifling process would work-harden the steel in the grooves.

It may very well, but the steel chemistry ultimately dictates how hard it'll get, and 416ss isn't going to go north of 42-44 C. Any well-made ream will make pretty quick work of that. It could actually help. Many action manufacturers that use the same material will heat treat the blank before chewing on it, as it helps to avoid distortion issues, and the finishes are typically better.