7 ultra mag

[7run]

i am trying to work up a load for hunting with my 7rum. i was using 90g rl-25 with 175g smk. what concerns me is brass life i am only able to get 3 reloads before the primer pockets began to open up. the pressure is not bad slight flating of primers but not excesive. I have herd that it is just the nature of the beast. Also i seem to be getting awsome speed with this load my chrono is saying 3520. so far i have used two differnt chronos and gotten the same readings. i am usign a hart barrel at 28in finised but i cant seem to see where i am getting all my speed. hornaday load has it only at 3100 with a 26in barrel i know the two extra inches will help but i didn't think that much. what im trying to ask is what speed do i really need to take game out to 700 plus. any info would be helpfull.

 

[billmo]

7run, you could throttle that thing on back to the 3100 fps and and still be fine as far as killing and you could probably find as good or better accuracy down there too. Your barrel will live longer by slowing your bullets down.,Speed kills barrels) I have a shooting friend that owns a 7RUM and I used to own a 300 RUM also. Have done quite a bit of shooting both of them. They are definitely killers but on both ends. Bill

 

[babyrou]

I been shooting 300 ultra + dealing with short case life for years,2-3 firings per case). I did this all @ the same time so I don't know what fixed it. Had Greg Tannel true action, reduce firing pin hole diameter + instal a Broughton 5C barrel to reduce pressure. Went back to Remington brass,tougher than Federal or Nosler). Went back to CCI-250 primers,harder cups, less expansion of primer cup in the brass). Set my Redding S-type bushing die up to that it just barely kisses shoudler. My full length re-sized brass measures .0005 @ 3 points on shoulder less than a fired case,minimum headspace). Spent hours getting that set up just perfect. I now get 8-9 firings per case @ 3450 with 180G Swift Scirroco + 94.5 grains of Retumbo,way off the reloading charts). I have a gunsmith friend that also had the same problem + he did this also + now also gets 8-9 firings per case. Very helpfull when you buy brass buy the 1000 lot + then do all of the prep + only use the best 200 cases out of the 1000 + then re-sell the rest to some-one who doesn't care.

 

[Preacher]

Any time primer pockets open up after 3 firings, it is usually associated with high pressure, or soft brass.
Your pushing those 180's awful hard, I would back off a couple hundred FPS at the least......

 

[AndyW]

I had a 7RUM and I gave the gun an honest effort. I could maybe get to 3050 fps w/ a 175 Sierra. Anything hotter and I would pooch the case. The gun was obnoctous to shoot. The best move I made was to re-barrel the gun and chamber it to a 7RM. I get 3000 fps with the 175 grain Sierra, better accuarcy, zero pressure signs, waaay less recoil and burn 25 grains less powder per cartridge.