Home Forums Reloading Big Game Rifles Modern data for the 7X57?

Don't know what H414 would give you in a long throated rifle, but we can roughly estimate the conditions required to get 2916 FPS using RL22 in my rifle.

2916 is 180 FPS faster than my load, which runs at 55.5 KPSI. A grain of powder yields about 65 FPS increase in MV, so 2.76 grains of additional powder would be needed to get that additional 180 FPS. A grain of powder is somewhere around 3 KPSI in this region. So 2.76 grains of powder will add 2.76 x 3 = 8.3 KPSI to the 55.5 KPSI I was getting. That's 63.8 KPSI, if I've done all my math correctly.

So it's a hefty load, and not one that I would choose to run.

IMHO and experience with 7x57's over the years, the throat length and the bullet shanks bearing length have been the determining factors in developing safe loads for my rifles. I also feel that when loading for this particular cartridge and again this is JMHO, given the different throat lengths of a lot of rifles out there, my best reloading tool and friend has been a chronograph and me keeping a close eye on it.

YMMV,
BD

Blackdog1 is right on the varying throat lengths. I had some 140 grain loads worked up in anM70 featherweight which I traded off in a moment of insanity. At the time I had it and a Mannlicher-Schoenauer with a 20 in. barrel and full stock. The 140's went 2900 in the 22 in. Win and 2825 in the 20 in. Mannlicher.

When I bought the Ruger, I shot some of these and they went 2675 fps in my 22 in. barrel! It was way longer throated, so the load obviously had to be adjusted. The load that goes 2950 in the Ruger would no doubt pop primers in the other two rifles, although I was smart enough not to try that. Use the chronograph and when you reach Denton's velocities above, stop.

As you notice even Atkinson's loads, while hot, are about the same pressure as a WSM, so aren't to the danger point. I'm not so sure that 3 grains will go 180 fps faster though either.

I've been shooting the 7x57 since my teens in the late 60's. Mauser'95,Ruger,Remington Mtn.,7x57AI.In all of them they will take more than most books list.I can load 51grs.of RL19 for 2892fps in my '95 and have been for years.The RL powders have less pressure per volume.In the other modern rifles it's nothing to get 2950 to close to 3000fps.In my 7x57AI I get 3070fps as a safe velocity again w/RL19.All of these w/the 139/140gr bullets.My Dad had an old paper can of H4831 back in the 70's that gave hyper velocities...but I forgot about it after ran out as I could find no more.I do however agree w/Bob in that those 3000+ loads in any rifle/throat for a standard 7x57 does give me the shivers. powdr

I've seen ray claim to get close to 2800 with 175's!
What a loon!

My mistake,2863!
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