low velocity .375 Win. loads

[gerry@fundy.net]

I am looking for a load for my .375 Win. that doesn't require gas checks.  I have had excellent results at higher velocities with gas checked bullets that were given to me by a friend.  The only mold I have is for a 248 gr. non gas checked bullet.  The few low velocity loads I tried didn't work well.  There doesn't seem to be much data out there for low velocity loads.  Can anyone help?
Gerry

[John Traveler]

Gerry,

For low-velocity .375 Winchester loads, use .38-55 load data.  It's perfectly safe because the .375 Win is proofed to higher pressures than the .38-55 (The reverse is NOT true!!)

The cartridge cases are almost identical except for length, and that 248 grain plain base bullet is perfect.  Size it to .375" or .376" (depending on your groove diameter) and load away.  A Lyman Cast Bullet handbook will list recommended loads.

I like Alliant Unique for plinking, and blackpowder for full loads.  For your low velocity loads, start with IMR 4198 or IMR 3031 powders.  Either one will give decent velocities with starting loads.

For air-rifle velocities, try swaged .375" round balls on top of small charges of pistol powders (WW231, Bullseye, etc).

[Sky C.]

I was out doing load development a couple weeks back for a new .38-55 Marlin.  Shooting a 265gr. GC design - I found that 16.0 grs. 2400 was giving outstanding accuracy with velocity running about 1260fps average - very mild.  It would be plenty mild for a PB bullet and I shouldn't be much different in your .375 even with the slightly smaller case capacity.


Best regards-

Sky C.