Does anybody have load data for this cartridge with cast bullets? I would like to try the RCBS 140 gr for silhoutte.

7mm-08 data is a good place to start, that's how I worked it with my 358X444, started with 358 winchester cast data and all went well. For Sillywets, you might want to try a bullet heavier than 140 for optimal results, though the 140 will work if you hit em right.

good luck,
graycg

This morning I compared the load data I got with the barrel for jacketed bullets and it appears they are on the starting to low side of 7-08 loads. This seems to me that you are correct to proceed with 7-08 data for cast bullets also. Just being cautious since the 7-08 "proper" is too much for a Contender frame. This case has ample volume to get into trouble with.

Basically you are shooting a 7x57 Mauser with a Rim. I realize your cartridge is a 7mm Bellm based off a 444 Marlin case. Case dimensions are virtually identical to a 7x57 Mauser.

Try the following data from Accurate Arms Powder:

Bullet - 145 (L) SPGC
Powder - XMP 5744
Charge - start at 18.0 grains to 27.0 grains max
Velocity - 1661 to 2238 fps
Pressure - 33,000 C.U.P.
Cartridge Length - 2.955

Also you can consult the LYMAN CAST BULLET Manual for the 7x57 Mauser to get other loads. Otherwise e-mail me and I will send you the data from lyman. I may have some data from RCBS's old cast bullet manual to.

7-30 Waters