barrel setback and rechamber question

[AZShooter]

I have a very worn 28" 6mm-284 barrel (1200 rounds) that I am considering shortening and rechambering for 6 BR. I have all the equipment to do it myself so cost won't be an issue.

Just wondering if it will work. Bore scope show horrific firecracked surface well up the barrel. It progressively improves but the first 6"-8" are not in good shape. The barrel still shoots quite well but fouls after 20 rounds and groups open up. Cleaning is a real chore.

I thought it might be fun to cut it off at 20"-22" . It would remove most of the damaged area and would still be useful as a 6 BR. Twist is 1 in 7.5 so any bullet could be used.

I have read of BR guys cutting off an inch or so and rechambering. Anyone ever chop off inches and reuse a very worn barrel?

 

[MTBULLET]

If you cut off "6-8" , does the contour allow correct tenon dia. ?

 

[IdahoCTD]

I just set back a .260AI 5" on the chamber end and cut 1" off the muzzle. The customer said it shot better than before. Your problem would be cleaning up enough of the fire cracking to make it worth wild. Cut off as much as you can to keep at least 1.2" of tenon diameter and give it a go. It's only your time. I would take 1" off the muzzle as well for a clean crown.

 

[J E Custom]

If I am going with the same cartridge or one that will clean the chamber up I set the barrel back one full thread and it places the barrel ID back in the right place.

When going with a shorter cartridge I like to remove the entire thread shank so I have the right amount if threads.

Normally unless the barrel is a straight taper with a long shank or a cylinder there will not be enough
shank to cover the cartridge. (I like the shoulder to be in the larger or at least in the transition of the shank to barrel start. (Where the barrel shank and the contour/taper starts).

The next thought would be to replace the barrel and end up doing about the same amount of work.
(With 1200 rounds down the barrel, it would be hard to guess how much barrel life is left).

I consider setting a barrel back as a means of freshening up a good barrel and only hope to extend the life of an accurate barrel.

This is just my philosophy and the way I do set backs.

PS: It is always fun to try something new as long as you don't expect to much from the outcome.

J E CUSTOM

 

[Michael Eichele]

I had a 6.5-284 barrel in the recent past that went south at 700 rounds. I had it set back 1", re-chambered, took 1/2" off the muzzle. Shot great for the next 100 rounds then crapped out again.

old barrels are good for cutting up into small pieces to make muzzle brakes out of.

 

[AZShooter]

Thanks everyone. The barrel is a huge bartlein that Bullets.com sells for F class. Its profile is perhaps a #13? Plenty of tenon diameter to work with that is for sure.

Michael thanks for your experience. I think that is exactly what this one will do, crap out in 100 rounds.

I don't think I'll bother as I would have to open up a different rifle's barrel channel to use it.

The original rifle has a new Bartlein SS 1 in 8 waiting to be installed. It is a shehane tracker and will be a 6 BR instead of the 6mm-284. Want to play around with the free recoil technique and have a much longer life to the barrel.