Maybe and my bet would be not needed for a very long time. I used my STW with 120's at 3600 for years shooting ground hogs, coyotes, varmints, rocks, etc. (many 3-4 shot strings in pretty rapid succession) basically I abused it. It has just a little over or under 1000 rounds down it. I would say 800 were the 120's, and last year I gave it to my son (killed his first bull with it) and we loaded up some 175ABLR at 3200+ and it still shoots .5"/5 shot groups.
Anyone able to get any 7mm Cartridge to 3300/160 or 3200/175gr?
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Mike Matteson
Well-Known Member
In a 308NM which is shorter than 7RM or a 300WM case to the shoulder. I achieved 3400fps with IMR4350, (26" barrel) 165gr Nosler BT, but it proved to be to hot because of temp sensitive powder. Change to H4350, and I am doing 3300fps now. It's not very temp sensitive. A friend had a 300WM getting 3400fps with out problems in a 24" barrel. So what I am driving at, is the case is about the same except bore DI. I am not for sure, but I think with load development you should be able to reach 3300lps with 160grs. The loads I develop were not touching the lands, I don't know in relationship to the lands they are.
I have a 7mmRM rifle, but never used it, and didn't do any load development with it. I was and still shooting 165gr Nosler BT or AB at the 3300fps in my 308NM. The load is Fed-210 primers, 75.grs of H4350, w/165gr BT Nosler or AB. They group@ 1/2": @ 100yds or under. Presently I am using a 338WM w/200gr Nosler BT or AB ,W-760 powder , Fed-210 primers @ 3200fps Rem case, in 24" barrel Ruger Mark 11. It accurate, but can be heat sensitive too. It was develop in the summer time in CaL So as long as the weather is hot it good to go, but in the winter it falls of in velocity. Never determine just how much.
If you are going to try something like that. Work you load up in .5grs at a time. These loads are 5 grs over book. GO SLOWLY AND CHECK EACH FIRED CASE FOR HIGH PRESSURE SIGNS. All my loads in those high powder areas have faltten primers, No creatoring, no ejector marks either. That's in my rifles. I have a 338WM being built with a 28" barrel on it. Someday I get it from the Smith to develop loads for it. I hope I can get away from the W-760 powder and use H, 4350, H4831, or H1000 to achieve the same velocity if possible.
It all goes back to load development, and being that it's doesn't take that much to do the work correctly. So that why I see that 7mm RM has the room to add additional powder in the case, but I think you can get the velocity up in the 7mm.
HOT LOADS AND MAYBE TO HOT FOR SOME RIFLES. GO SLOWLY, AND IN ONLY .5GR INCREASES PER CASE. WATCH YOUR PRIMER FOR SIGNS OF OVER PRESSURE.
hOPEFULLY THIS MAY HELP!
I have a 7mmRM rifle, but never used it, and didn't do any load development with it. I was and still shooting 165gr Nosler BT or AB at the 3300fps in my 308NM. The load is Fed-210 primers, 75.grs of H4350, w/165gr BT Nosler or AB. They group@ 1/2": @ 100yds or under. Presently I am using a 338WM w/200gr Nosler BT or AB ,W-760 powder , Fed-210 primers @ 3200fps Rem case, in 24" barrel Ruger Mark 11. It accurate, but can be heat sensitive too. It was develop in the summer time in CaL So as long as the weather is hot it good to go, but in the winter it falls of in velocity. Never determine just how much.
If you are going to try something like that. Work you load up in .5grs at a time. These loads are 5 grs over book. GO SLOWLY AND CHECK EACH FIRED CASE FOR HIGH PRESSURE SIGNS. All my loads in those high powder areas have faltten primers, No creatoring, no ejector marks either. That's in my rifles. I have a 338WM being built with a 28" barrel on it. Someday I get it from the Smith to develop loads for it. I hope I can get away from the W-760 powder and use H, 4350, H4831, or H1000 to achieve the same velocity if possible.
It all goes back to load development, and being that it's doesn't take that much to do the work correctly. So that why I see that 7mm RM has the room to add additional powder in the case, but I think you can get the velocity up in the 7mm.
HOT LOADS AND MAYBE TO HOT FOR SOME RIFLES. GO SLOWLY, AND IN ONLY .5GR INCREASES PER CASE. WATCH YOUR PRIMER FOR SIGNS OF OVER PRESSURE.
hOPEFULLY THIS MAY HELP!
7Rum Slayer
Well-Known Member
I have ran 180's and 175 Berger's to 3350 in my 26" 7 Rum with excellent accuracy with Retumbo. My 26" 7 Rem Mag pushes the 168 Berger to around 3140 with H-1000. Both shoot very good at distance and are mild loads in my rifles. RL 26 may get you more velocity out of your 7Mag but I have never tried that powder to confirm. Hope this helps. Cheers, Jason
The R26 went wonky on me when the temp got over 85 here. I try to work up my loads when its cold (when I usually hunt) R33 was fine. I used Retumbo for my SIL's 300 RUM/200 NAB, right at 3100. I got 3500/180 NAB from a 338 RUM, so I haven't missed out having a fast 7mm, was just always enamored with the "idea" I guess of that 160/3300fps!
The problem I see nowadays is that most reloading manuals for the big 7s (STW & RUM) list moderate and conservative loads. If I am going to shoot my 7mm RUM, I am going to maximize my velocity while staying around that 62-63k psi range. Just a thought.
Agreed sir! I want as close to 64K as I can get with, but with accuracy, in just about any '06 case capacity or Magnum. But my old 7mm RUM was one fickle devil! It shot the 140s best, and while I never checked the twist, I suspect it was 10". Or a very slow 9 1/4". The 26" STW was a Mod 70 Sporter Classic that I had Hill Country Rifles accurize. It still wasn't consistently accurate with the 160 Partition. Levelled off around 3150. Never tried the 175s in either.
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comfisherman
Well-Known Member
My first 7 rum was a sendero with a radial brake. When it got rebarreled I duplicated the external profile of a little over 29 in but full Barrel with no break. Keep in mind this is 15 years ago were longer barrels were kind of the norm like shorter barrels are the norm now. For raw performance with that big of powder column that extra barrel length really makes it do amazing things with the feet per second.
The mashburn is pretty much a 7mm-300 win mag. Which is bigger than a 7rem mag by a few grains, it wouldn't have a problem reaching those speeds, especially with today's modern powders. The powders we have today make magnums hammer.
comfisherman
Well-Known Member
Have we considered that maybe they're measuring devices were abysmal and some of those feet per second could be chalked up to the gray area of "I think we hit this speed."
Probably done with bullet drop charts, and radar
