I'm a newbie to reloading so this might be a stupid question but I have data for reloading that doesn't specifically mention H322 powder and Cast bullets. I am using data that covers H322 Powder with a starting load of 27 grains and 255 Jacketed bullets at 1540 fps

Can I substitute a 260 grain cast bullets with the same powder load?

Just learning cast is much cheaper then jacketed bullets. Thats how green I am!

Going to have to make an assumptions here...the caliber of that rifle...with a 255gr. Jacketed bullet being used, am I safe in guessing 38-55?

Yes, 38-55. Cool gun got me into reloading because of the lack of ammunition. Glad it did. I'm really enjoying reloading. Just put a Williams FP sight on the gun with a Fire front sight.

The Winchester loads shot pretty good. I want something with a bit more omph now.

Yes, 38-55. Cool gun got me into reloading because of the lack of ammunition. Glad it did. I'm really enjoying reloading. Just put a Williams FP sight on the gun with a Fire front sight.

The Winchester loads shot pretty good. I want something with a bit more omph now.

Depending on the hardness (and diameter) of the cast bulelts, pretty safe starting with the same starting load as tje jacketed 255gr. Just work up in steps,and feel free to stop early if accuarcy shows a peak.

I'm going with .378 cast performance bullets on midwayusa. Thanks for the information.

I'm going with .378 cast performance bullets on midwayusa. Thanks for the information.

Ok..those would be plain based (actually, if you look close, the base is a little beveled...the automatic casting machines hate sharp edges) and proably lubed with some kind of rock-hard lube (colored blue more times than not), then dusted with a white powder to cut down on the "sticky" for boxing and shipping. IF they are the ones I'm thinking about, have one lube groove, one criump goove. May shoot fine, but I'd be betting on the lower velocity being more accurate than the higer velocity loadings.
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My mistake...looked them up...are the BETTER cast bullets, with gas check and multi-lube grooves (but still with that blue hard lube). Those may hold velocity to the same limits (or near to them) as the 255gr. jacketed bullets do.

Still going to be a matter of bore diameter vs. bullet diameter, but for your use, can start with the suggested minimum load and work up carefully. IF the lead is going to case a problem over jacketed bullet data, it will do so once the pressure has passed the yield point of the alloy...that won't be at the starting load, but may be well before the max. listed for a jacketed bullet.

Thanks Ribbonstone for all the information. Yes, Here is the bullet:

http://www.midwayusa.com/rewriteaproduct/266254


I bought a hundred of them to start. I opted for the .378 caliber so that limited my choices.

Thanks Ribbonstone for all the information. Yes, Here is the bullet:

http://www.midwayusa.com/rewriteaproduct/266254


I bought a hundred of them to start. I opted for the .378 caliber so that limited my choices.

Think that data for the RCBS #37-250-FN or the Lyman #375449 would be close to matching that bullet...both are of about the right weight, shape, and are both gas checked.

None of the manuals at hand list H322, but that's not to say it can't be a good powder for the 38-55, just that I'd have to hunt up more data. H322 seems to be in the range of speeds that would be useful.

Comaring lead to jacketed data, the powder charges is nearly always less...part if that is simply becasue lead bullets of this weight are longer/seated deeper and that reduces case volume. May consider starting lower than 27gr...say something in the 23-25gr. range.