Vel. cast Vs. jacketed

[RU shooter]

Since I have no cast load data for my 30/30 I'm just sort of guessing at the vel. since I'm using reduced jacket data, For those of you that have chronographs is there a direct correlation between cast and jacketed velocities using the same charge weight. In a for instance I found a load thats shooting good for me in the 30/30 ,30.0 gr H380 and a lyman 311466 at 154 gr with lube and chex.My Speer manual says this is moving 1675fps with a 150 JFP. Soooo is my boolit faster ?the same ? slower? I assume a little faster due to less friction But how much 50 fps. more ?Yeah I know I need to buy one of those chrono things! thanks.

Tim

[beagle]

Not having experience with that powder, I can't comment on actual data but as a general rule, cast bullets give more velocity with the same powder charge than does a jacketed bullet of identical weight out of the same caliber cartridge.

Less friction....../beagle

[Bret4207]

Like Jon said- less friction. But the end result depends a lot more on fit, actual boolit weight, etc. The burn rate is altered by the variations in your boolit. I don't think there's a hard and fast rule for correlation beyond cast usually running at less pressure.