I recently had a proof barrel put on my .300WM Sendero. I'm working on developing a load, and have yielded good results from 70gr of IMR4831, with a Nosler AB 180gr. In fact that is the same recipe for the weapon prior to adding the new barrel.
Here is my "hmmmm" moment. I had no indication of over pressure from that build. No bulging, cracking, sticking, and primers looked good. HOWEVER...when I went up to 70.5 during my test, my case was stuck and I had to try quite a few times to get the bolt to latch on and extract. This was the same for all of the rounds loaded at 70.5. At 71 gr I had to use a rod to get it out. I tested it again with a factory load and had no issues with extraction. All my cases are full length sized and under max case length. Bullet is seated .005 off lans. The max load for that powder is 73.
Why this worries me is if I'm getting stuck with a .5 gr increase going 70 to 70.5, is 70gr too risky to use when hunting? I was lucky enough to draw a moose tag for my home state and can't have a stuck case screwing that up. I don't know if temp changes will impact the material enough to where even the expansion for my 70gr charge will cause the case to stick. Could it be something else??
BearDog, I do not have ideas about what to do with your rifle, I find that there are too may variables to start making suggestions. What I can suggest to remedy any possible ammunition failures on a hunt is what my son and I do. We both hunt with 35 Whelens and .358 Winchesters, so not your average, everyday, run of the mill cartridges that you will find in WalMart or your friendly neighborhood sporting goods store that sells ammunition, cold remedies, oat meal and clothes. Three of four years ago while on a bear hunt in Maine we ran into a situation where we had a bad batch of primers (hard anvils) and were experiencing FTF rounds. Not every round, but.....as in your situataion who needs to head out into the field with doubt on a once in a lifetime hunt??? So.....we head out to the nearest
"super" sporting goods store two hours drive away to see if we could pick up some ammunition for the only two guns we had. They didn't have the 35 Whelen ammo, but they did have three boxes of .358 Winchesters, so.....we bought then for the hunt at $80 a box!!! We felt like we got bent over, but what could we do??? We figured that we had ten rounds each to get our rifles sighted in and a box each to hunt with; we don't shoot 500 yards hunting black bear in Maine! We managed to harvest bear with the factory ammunition, however we would have preferred to be hunting with our 225 gr Barnes TSX and 200gr TTSXs instead of what we were shooting. After that experience we always take along
at least two rifles and
at least two boxes of factory ammunition just in case we do run into a situation with our reloads. I have been reloading for 55+ years, really make good ammunition; however, sometimes
components can let you down. I know that this does not resolve your rifle problem, hopefully it will help to rid some of the doubt you may have with a rifle/ammunition that you do not trust on a trip that you were lucky enough to draw a moose tag from a lottery. As for the rifle issue, I would start out with a new batch of brass, annealed and prepped properly, and go with SAAMI specs for my hunt and tweak/ladder test your loads until I found a load that worked in my rifle, AND take that load with me on the hunt, along with some factory ammunition that may not be as accurate however dependable. Good luck with your moose hunt.