.38 Special velocity from a carbine???

[Southern Shooter]

I have a Marlin 1894C. I am roughly aware of the .357 magnum velocities from this gun. However, I do not know what velocities I could get from this gun with:
1) 125 grain +P that run 950 fps from a 4" revolver
2) 158 grain +P that run 890 fps from a 4" revolver

Anyone have an idea?

 

[wcwhitey]

Roughly about an extra 100 fps. It is really hard to tell though, it more depends on the powder that is used in the load. If it is a fast burner not much gain will be seen. If it is a slow burning powder it can take advantage of the extra barrel length. The .357 picks up so much because it uses slow burning powders like 296, H110 or the commercial loading equivalents, the .38 not so much.

 

[Dave B]

You gain 2-300 fps with the longer bbl. 158 gr lead with 5gr Unique= 1150 in 94C ,950 fps in 6" Ruger. With 125 gr bullet, 5gr Unique,=1175 rifle, 875 pistol. A 105 gr lead SWC with 2.7 gr Bullseye makes 830fps in 6" pistol and 1000fps in 18" rifle. It's true you get a little more gain in longer bbl with slower powders.