I've never had this happen before in the many barrels I have chambered. I would appreciate any input you can give me. Brand new reamer, 2/3rds. the way through the chamber, oiled everything up, seated the reamer and just started to move it in (0.010"-0.015") and it like caught and broke the handle off of my Bald Eagle Reamer Holder. I removed the reamer and it didn't look like it was damaged. Bore scoped the chamber and couldn't see anything really out of place. Sanded the chamber, fixed the handle on the reamer holder and inserted it again and that's when the reamer caught again and broke. I ream at 90 rpm and feed it pretty slow, lots of oil.
Any input would be much appreciated. I have enough room to cut the tennon off and start again, but don't know if that's the fix.
Thanks for the help.
I was cutting a 375 H&H Improved a while ago and the exact thing happened to me.
Dave replaced the reamer no charge and when the flute broke off it didn't marr up the chamber it just took 3 months to get the new reamer.
I've managed to do the samething when step reaming holes more than I'd like to remember. Looked at all sources for the trouble, and it always came back to two or three things. Excessive tool pressure due to the coolants breaking down, and chip build up. My boss told me once to actually take an Arkansas stone and dull the reamer a little bit, and that helped. On production lines you often see this, and almost everytime it's surface speed related with an excessive chip build up in the flutes. Remember that your really cutting with the entire surface of the reamer instead of simply reaming a strait hole. You didn't say what material you were reaming, but one has to think stainless steel, and that stuff can often get kinda gummy like like (like reaming 1010 thru 1020CRS). An undersized hole your following will also cause you havoc.
TM, I think they pump those reamers out so fast, the get the rake and clearance angles screwed up. I had a new, customer supplied PT&G in .270 Win. 'stall' 2/3 of the way in to a SS Shilen Match. I removed the PT&G from the holder and put my Manson .270 reamer in and finished the chamber with NO problems.
"Shoots real good!": definition; it didn't blow-up in my face. 1993 graduate Montgomery Community College 2yr. gunsmithing program