A guy showed up at the shop yesterday with a model 70 classic in 300 WSM saying he was having inconsistent problem with chambering full length sized rounds. I went through it, checked the settings on his sizing die, bolt clearance in the action, extractor clearance, headspace check, etc, all checked out OK. Could not come up with an answer so decided to pull the barrel. When I did, I put in my reamer and turned it by hand. I could feel it cut a small amount, pulled out the reamer and guess what, two shiny spots in the chamber near the back on opposite sides. THE CHAMBER WAS OUT OF ROUND!
The rifle belonged to his brother in law and he only shot factory ammo and had shot it for years that way. The deal with not fitting, if he took a full length cartridge and tried it in the chamber, unless it was oriented the same as when it was fired, it would not fit. How did Winchester cut a chamber out of round???
Jim
I know that YOU know the answer to that as easily as I..
But part of the problem was alleged (note: alleged) over-tightening of the barrel to the receiver.. Yeah, it's been written about. So has global warming.. Both taken with truckloads of salt.. IMHO that would take one helluva lot of torque to get to that point..
My question is: why was this phenomenon supposedly only with WSM rounds and not other magnums etc?? Do they not tighten the barrel (roughly) the same on each rifle? Wouldn't THAT cause egg-shapes on others? Why only WSMs?
One way to find out if your barrel could be an over-tightening problem is noting exactly where those two spots are. Do they coincide with the center of the uninterrupted thread section of the receiver? Or not?
FWIW I've run into egg-shaped chambers on Rem 700s too - and it had nothing to do with WSMs or interrupted threads..
YMMV
