Barrel rechamber/setback hard on reamer?

[Phys86]

I read a comment in a thread that rechambering used barrels is bad for the reamer, even if the barrel is well cleaned.

I have a barrel I was considering having set back (600 30-284 rds) and another barrel that is a factory Tikka barrel (100ish .308 rounds) I was thinking of having rechambered.

I own the reamer and want to keep it in as good of shape possible. It's Manson's standard reamer steel, so I think HSS but not sure.

Would that be a bad idea if I'm worried about damage to the reamer?

 

[gunsandgunsmithing]

I read a comment in a thread that rechambering used barrels is bad for the reamer, even if the barrel is well cleaned.

I have a barrel I was considering having set back (600 30-284 rds) and another barrel that is a factory Tikka barrel (100ish .308 rounds) I was thinking of having rechambered.

I own the reamer and want to keep it in as good of shape possible. It's Manson's standard reamer steel, so I think HSS but not sure.

Would that be a bad idea if I'm worried about damage to the reamer?

This reamer had cut 40 or so chambers and multiple setbacks before cutting this one. It still does a great job.

 

[Phys86]

I will be lucky to wear out this reamer in my lifetime

 

[DShortt]

I would discuss this with whichever gunsmith you are considering to do your work and see what their thoughts are.

 

[jackieschmidt]

I set back my barrels on a regular basis. I have been using the same 30BR and 6PPC reamer for a number of years. Both have chambered and set back multitudes of barrels.

One item of note. I do not ream with power. I rough bore the chamber and use the reamer to simply establish the final dimensions and finish, turning it by hand.

 

[Webster]

I read a comment in a thread that rechambering used barrels is bad for the reamer, even if the barrel is well cleaned.

I have a barrel I was considering having set back (600 30-284 rds) and another barrel that is a factory Tikka barrel (100ish .308 rounds) I was thinking of having rechambered.

I own the reamer and want to keep it in as good of shape possible. It's Manson's standard reamer steel, so I think HSS but not sure.

Would that be a bad idea if I'm worried about damage to the reamer?

Why would you set back after so few shots. Don't believe everything someone post on internet. Never saw an article, especialy by a good source that had proof the the eroded area increased in hardness that might not be good for the reamer. i have read research aticles on internet conducted for the Military where they proved the metallurgy of the barrel was slightly changed by a very shallow depth. I think it had to do with nitrogen entering the dteel? Will try to find the article and post it.

If a gunshith with experience cutting chambers on an eroded chamber would comment on reamer wear/damage I would trust his opinion.

Thermo-chemical erosion in gun barrels

When a gun fires the metal temperatures at the bore may reach 1100°C in a few milliseconds and decline to half this value by the time the projectile r…

www.sciencedirect.com

I think there are several other articles.

 

[Phys86]

Why would you set back after so few shots. Don't believe everything someone post on internet. Never saw an article, especialy by a good source that had proof the the eroded area increased in hardness that might not be good for the reamer. i have read research aticles on internet conducted for the Military where they proved the metallurgy of the barrel was slightly changed by a very shallow depth. I think it had to do with nitrogen entering the dteel? Will try to find the article and post it.

If a gunshith with experience cutting chambers on an eroded chamber would comment on reamer wear/damage I would trust his opinion.

Thermo-chemical erosion in gun barrels

When a gun fires the metal temperatures at the bore may reach 1100°C in a few milliseconds and decline to half this value by the time the projectile r…

www.sciencedirect.com

I think there are several other articles.

Thanks for the article. Interesting!

Reason for setting back is to fix the current chamber job (likely cut too large) and the rechamber is for turning a 308 barrel into my cartridge.

 

[Judd]

Some guys do it some guys don’t. If the original chamber isn’t one he’s cut he could be inheriting problems…meaning if the original chamber is over sized or not straight.

I have never thought a rechamber was a good idea, unless you have the lathe and do your own work. The smithing charges should be the same or more (see inherited work comment above) and all you save is the cost of the barrel.

Good luck, with the way Tikka is consistent on HS measurements…I’d sell it to someone who wants a 308 and cover half the cost of your new barrel. My opinion, you come out better in the long run.

 

[Bill K]

Maybe I don't get it, but how would a reamer know if it is cutting a new chamber or just cleaning up one in a set back barrel ? I would think there would be no issues doing it.

 

[Alex Wheeler]

I have ruined more than one reamer on used barrels. It all depends on how bad the barrel is and how nice you want your reamers to cut a lead. The damage occurs on the edge that cuts the lead angle. If you have a special reamer you baby it, you cant replace those. But on standard stuff I will inspect the barrel and decide. If theres little to no cracking I will do it. But if its bad, nope.

 

[Dimner]

I have ruined more than one reamer on used barrels. It all depends on how bad the barrel is and how nice you want your reamers to cut a lead. If you have a special reamer you baby it, you cant replace those. But on standard stuff I will inspect the barrel and decide. If theres little to no cracking I will do it. But if its bad, nope.

Hypothetically, In those cases that you will not set a barrel back... Is there a certain length of the barrel you could lop off, starting the chamber from there to avoid reamer issues?

 

[Alex Wheeler]

Hypothetically, In those cases that you will not set a barrel back... Is there a certain length of the barrel you could lop off, starting the chamber from there to avoid reamer issues?

Yes, you bore scope the barrel and if theres enough shank to get to good barrel you cut it off.

 

[durand mortenson]

This reamer had cut 40 or so chambers and multiple setbacks before cutting this one. It still does a great job.

View attachment 1530527

Nice finish!

Mort

 

[Will Henry]

I have not experienced any reamer damage from rechambering, and I have been doing it for almost fifty years. I have to mention, in many cases, the old throat is bored or drilled out prior to reaming. WH

 

[Phys86]

Thanks for the notes. I'll make sure to ask ask the gunsmith about his process and see if he thinks it would be doable without damaging the reamer. I may not have enough shank left to setback the one barrel.

The purpose of rechambering the Tikka 308 is because they're good factory barrels and certainly meet my accuracy needs for practice and hunting. A stainless takeoff 308 is typically pretty cheap, so it's a good way to get a cheap and functional blank.

 

[Sniperhandle]

Thanks for the notes. I'll make sure to ask ask the gunsmith about his process and see if he thinks it would be doable without damaging the reamer. I may not have enough shank left to setback the one barrel.

The purpose of rechambering the Tikka 308 is because they're good factory barrels and certainly meet my accuracy needs for practice and hunting. A stainless takeoff 308 is typically pretty cheap, so it's a good way to get a cheap and functional blank.

Tikka Barrels have been pretty tough material to ream, I have re-chambered a few new take off varmint contour barrels. The material they use is very sticky feeling and I have not damaged a reamer yet, But It just feels wrong when you are chambering, At least that has been my experience. They shoot very well though.

I did a 1-8 new take off 6.5 crudmoor and re-chambered and rethreaded in 6.5 PRC. Have done a couple 308 win. also.

 

[Larry Koch]

If you don't do your own barrel work it's point less. However on my own barrels which are HV or LV. I will set back one time. The Reamer does so little of the finished cut not sure how it could damage it.. I will recrown them also. I've had good success where the barrel come back to life for another 500 plus rounds, for me it's worth it. But if a barrel is shooting good, Just keep shooting it until it gives up the ghost. I don't know that I've ever had a bad barrel yet. I'm convinced the top barrel makers are worth it.

 

[jackieschmidt]

Several members make good points.

Unless you do your own barrels, it is probably not cost affective to have someone else set a barrel back. Most Gunsmiths shy away.

The way I chamber my barrels makes it particularly easy for me to set them back up in exactly the same manner as the original, and do a set back I have one historically great 1-18 30 caliber Krieger that I have set back three times. It is down to 20 inches and I would still take it to any match in the Country.

 

[boltfluter]

Several members make good points.

Unless you do your own barrels, it is probably not cost affective to have someone else set a barrel back. Most Gunsmiths shy away.

The way I chamber my barrels makes it particularly easy for me to set them back up in exactly the same manner as the original, and do a set back I have one historically great 1-18 30 caliber Krieger that I have set back three times. It is down to 20 inches and I would still take it to any match in the Country.

Jackie,
How do you set up your barrels for chambering? Just curious is all. Krieger has always been my personal favorite.
Paul

 

[Phys86]

Tikka Barrels have been pretty tough material to ream, I have re-chambered a few new take off varmint contour barrels. The material they use is very sticky feeling and I have not damaged a reamer yet, But It just feels wrong when you are chambering, At least that has been my experience. They shoot very well though.

I did a 1-8 new take off 6.5 crudmoor and re-chambered and rethreaded in 6.5 PRC. Have done a couple 308 win. also.

I wonder if the fact that they're hammer forged makes them work hardened and thus harder to ream