Home Forums Hunting & Shooting Handguns Max Vel in the 357 Magnum with Cast Bullets

A 10bhn hollowpoint would be a good place to be

The only reason for a 5 bhn hollowpoint is 700-800 fps muzzle velocity. So it's a bullet designed for a snubby 38 sp. As a very crude ballpark rule of thumb for cast hp's, multiply the bhn by 100 to figure out what velocity they will need to expand.

Yep.

It also depends on caliber and how flat the face is to begin with.

since i have a couple of pounds of Unique i will try 6.0 gr with this bullet in my 686 4 inch and GP100 in 6 inch if it leads i will then use 38 SPL brass

I have to disagree; that "method" is so crude that's it's meaningless, and not a method at all since it doesn't work. Size and shape of the hollow point cavity is far more meaningful than hardness values for determining expansion. You can easily have a 5 bhn hollow point that won't expand at 1200 fps, or a 10 bhn hollow point that will expand at 600 fps. I've done both. Another example is the solid copper Barnes hollow points - the 45 cal version I tested (200gr IIRC?) expanded at 700 fps, and is far harder than even hard cast lead.