38 Short Colt recipes

[jski]

I’m looking for something to drive a 105 grain bullet passed the supersonic threshold.

FortuneCookie45 used 4 grains of Universal to compare case efficiency: 38 Short Colt vs 38 Special. He got on average 350 FPS greater velocity from the 38 Short Colt brass. And amazingly he was using 158 grain bullets and averaged about 1075 FPS with them.

I’m thinking of starting with 4.5 grains of Titegroup.

[Outpost75]

You don't say what revolver you are using these in. Faster powders such as TiteGroup or Bullseye will work better than slower ones such as Universal or Unique, but the 4.5 grain charge of TiteGroup you propose will likely approach pressures expected for .38 Special +P.

Without knowing the intended purpose I cannot comment on the feasibility of attempting to load a light bullet to high velocity. The higher pressur4e and increased free bullet travel (jump) in a .38 Special chamber is likely to cause leading, base deformation and poor accuracy. I do not see the point.

I would be inclined to limit such experiments to light loads approximating factory ammunition in the .38 Short Colt, about 2.0-2.5 grains of Bullseye. If you gave more info on the revolver to be used and your objectives I may be able to comment further, but I think you are barking up the wrong tree.

[jski]

I’ll be using my classic K-frame 357 circa 1979 with a 4” barrel.

[Outpost75]

I’ll be using my classic K-frame 357 circa 1979 with a 4” barrel.

Your proposed 4.5 grains of TiteGroup should work fine in a .357

[jski]

Interesting! This is Starline brass:

9mm: 0.748 - 0.754 O.A.L.
38 Short Colt: 0.754 - 0.761 O.A.L.
​
The result being the 38 Short Colt actually has slightly greater case capacity than the 9mm.

That makes me think about using 9mm data.