Do any of you know how much more case capacity
this has than the 6.5 Swede? Bohica, if you are there how about some good loads?

Dear Sambubba,
I used Win brass and got a max of 51.0/4350 and 3100 with the 129 Hornady SP bullets. Case life was kinda short so I made cases from Lake City NM 30-06 cases and was only able to get 48.5/4350 in them before hitting max. NOW! This was in my rifle [BSA with McGowan xx barrel] so approach this cautiously in your rifle. The velocity was 3070 in the NM cases. The accuracy was BETTER with the mil cases than the Win. Go figure????? Accuracy was so good I never tried other powders. Why screw with success? I just got off the phone with a guy from E. Or who has one I built on a Mauser Mex with a McGowan barrel. This load works for him too. Maybe it`s just McGowan barrels LOL Hope this helps.

Aloha, Mark

quote:

Do any of you know how much more case capacity
this has than the 6.5 Swede? Bohica

The 6.5x257IMP will only gain you a couple gains of capacity. I show a 4.2gr gain in the 257 to 257IMP. I show the 6.5-55 to be 2 grs more than the 6.5X57.

As to Bohicas loads I can't get Loadtech to give me anything close with 4350 under 70,000psi. But it has been wrong before and each rifle is somethng new.

Thanks for the replies guys.

My father-in-law did one on a Arisaka action in 1952. The guys who built it called the cartridge the 6.5 Grover and Osborne. He loads 51 gr of H4831 and 120 gr boolets. He's been doing it that way for over 50 years and he's not about to change. Only bad part is he did it with an 18" barrel. Velocity suffers at 2700 fps and lots of muzzle flash. Case life is short to about 3 to 4 loads. I wonder if 6.5x57 cases might last longer?