Reamer sticking in chamber

[msalm]

Without pre-boring I’d say you have a bore that’s wandering off center. The deeper you go, the more binding you have between the pilot and the ‘line’ the reamer wants to travel. I’ve noticed this on longer chambers occasionally where I left more material for the reamer to cut at the front. If you drill most of the chamber and indicate at the throat/pilot area, and then bore the drilled portion, there’s a greater likelihood of keeping things straight. I think your reamer is just trying to follow the bore and now it’s a few thou off the centerline of the reamer.

 

[Edd]

Without pre-boring I’d say you have a bore that’s wandering off center. The deeper you go, the more binding you have between the pilot and the ‘line’ the reamer wants to travel. I’ve noticed this on longer chambers occasionally where I left more material for the reamer to cut at the front. If you drill most of the chamber and indicate at the throat/pilot area, and then bore the drilled portion, there’s a greater likelihood of keeping things straight. I think your reamer is just trying to follow the bore and now it’s a few thou off the centerline of the reamer.

Having an issue I’ve not ran into before. Been chambering a 6.5 PRC for a customer and after I make each cut I stop the lathe and go to pull the tailstock back along with the floating reamer holder and reamer but it won’t come out unless I reverse the wheel right as the lathe chuck is about to stop. I don’t have a flush system nor do I pre bore. I’ve only done a handful of barrels but haven’t ran into this before. I was taught never to pull the reamer out with the barrel spinning. The gunsmith that trained me does it this same way and doesn’t have any idea unless it’s an issue with the reamer itself. I tried removing the pilot and going back in to see if the pilot was causing it but it still does the same thing. Any ideas?

 

[jackieschmidt]

Strictly from a Machinist point of view, I don’t think you have a problem. Your reamer is cutting exactly to size.

In all if my chambers, the reamer fits a tad snug for the last 1/8 inch or so if I insert it back in the reamed chamber.

I would be disappointed if it did not.

 

[WayneShaw]

A fellow had PTG send a new reamer to me to chamber a barrel for him, a "blue box 6BR" as they called it. It wouldn't cut at all, and I drilled and bored before even trying it. I called Kiff back then, he had another in the mail that day and I sent that one back. The new one cut fine.

 

[Sniperhandle]

A fellow had PTG send a new reamer to me to chamber a barrel for him, a "blue box 6BR" as they called it. It wouldn't cut at all, and I drilled and bored before even trying it. I called Kiff back then, he had another in the mail that day and I sent that one back. The new one cut fine.

I have zero confidence in them, Even if it cut right, What other measurements and angles could be wrong?

 

[Alex Wheeler]

Snug is good, tight is when they start getting dull. Cant put it in words it more of a feel thing. Even if its new, doesnt mean the angles are right.

 

[DShortt]

Without pre-boring I’d say you have a bore that’s wandering off center. The deeper you go, the more binding you have between the pilot and the ‘line’ the reamer wants to travel. I’ve noticed this on longer chambers occasionally where I left more material for the reamer to cut at the front. If you drill most of the chamber and indicate at the throat/pilot area, and then bore the drilled portion, there’s a greater likelihood of keeping things straight. I think your reamer is just trying to follow the bore and now it’s a few thou off the centerline of the reamer.

That's an interesting idea.

Hopefully some experienced machinists will chime in with some input.

Maybe from the 'no prebore' perspective, simply to entertain a worst-case scenario.

My initial thoughts are, if that were the case, the rear of the chamber will measure oversized compared to the reamer.

 

[geo.ulrich]

I've been pulling the reamer out of a turning barrel for fifty years, never have seen any problem. Having said that, it sounds to me like the margin on the cutting edge is wrong. It happens, more with some makers than others. WH

I'm going with this also, take some dykum and coat the reamer. clean out the chamber GOOD with compressed air and brake cleaner. place reamer in chamber and twist by hand. Pull it out and check the margins...It should only scrape off a very thin edge

 

[jackieschmidt]

Snug is good, tight is when they start getting dull. Cant put it in words it more of a feel thing. Even if its new, doesnt mean the angles are right.

^^^^^^^^^