Why 357 Short Barrel ammo

[anchors]

Why does Speer make their SB 135gr ammo for 357,I thought velocity even from a 2" barrel in 357 would be sufficent to get expansion?

 

[scooter123]

It's about efficiency. If you use a round optimized for a 4 to 6 inch barrel, a lot of potential energy will go into producing muzzle flash and not velocity. Use a faster burning powder in combination with a somewhat lighter bullet and almost all of the charge will be spent getting the bullet up to speed with a lot less muzzle flash. I also suspect that as muzzle flash is reduced, the volume of sound produced will also go down, so it will be a bit quieter, which might be the difference between permanent hearing loss or temporary hearing loss.

 

[SWAT Lt.]

The SB rounds are designed to expand at lower velocities and to penetrate adequately. Therefore, the SB rounds can be loaded lighter for quicker recovery time between shots, and more contollability from small frame, short barrel guns. They are somewhere between a 38+P and a full house 357 Magnum.