just bought me a 7mm rum.i burnt 2 boxes of rem 140gr. factory ammo.i saw signs of high pressure on the case heads and the primers were puckering.when i went to reload these cases the primers seated very easy!anyone else out there run into this?
What kinda primers are you using? Have been hearing that Winchester primers sometimes run a tad bit smaller, therefor easier seating. Rem brass is not that great or tough. With that said, my 300 RUM's are max loaded and I have gotten 6 firings out of my cases and primer pockets are still ok. I bought 1 box of factory 180g NP's for my 300 RUM when I first got it to get some brass. I had the same problems with ejector marks. My velocity for them were 3300fps from factory.
I have never fired a factory loaded catridge through my 7mm Ultra Mag but I usually run my loads to the max in this catridge and have reloaded five times without any problems with loose primer pockets. I am using Retumbo with 160 acccubonds at 3400fps and see no excess pressure signs at all. After five fireings I do anneal the case neck.
I have never fired a factory loaded catridge through my 7mm Ultra Mag but I usually run my loads to the max in this catridge and have reloaded five times without any problems with loose primer pockets. I am using Retumbo with 160 acccubonds at 3400fps and see no excess pressure signs at all. After five fireings I do anneal the case neck.
I loaded my 7mm rum with the load jbdre gave me 160 accubonds with 94 grns retumbo and federal match primers. I used the primer pocket tool and when i primed them with my rcbs hand primer they went in very easily, i thought anyways but i am new to reloading also. We had no problem at the range and they looked fine after shooting. we tried factory 140's and were getting 1.5-2.0 inch groups . With the 160 accubonds we got several 1.0 inch groups at 100 yrds. and a couple 3/4 inch, one group you could cover 3 shots with a nickel..Hope you get the same results..
