RANGE REPORT: Win .375, Lee 375-250, 7383

[Jim]

As recorded in my chrony log book:

28 JUN 13
WIN. BIG BORE, .375 WIN.
LEE 375-250-RNFP
GRAPHLOX
IMR 7383
COL- 2.460

100 % case density- 29 grs.

30 grs.- 1379 FPS, no pressure signs, unburnt powder
31 grs.- 1401 FPS, slight pressure signs, unburnt powder but less that 30 grs.
32 grs.- 1449 FPS, slight pressure signs, unburnt powder same as 31 grs.
33 grs.- 1444 FPS, moderate pressure signs, no unburnt powder, indicative of peak performance
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33 grains required a fair amount of pressure on the press handle to seat the boolit as this charge is 10% above case capacity. A moderate roll crimp was required to keep the boolit seated.

I think 1450 FPS or so is about all I'm going to get out of 7383 in this combination. That being said, I'll drop back to the 30 grain load for recreational loads and switch to 3031 in pursuit of higher velocities.

[WILCO]

Great report Jim. Was Mr. Bill involved in the loading of these rounds?

[Jim]

Great report Jim. Was Mr. Bill involved in the loading of these rounds?

Oh, absolutely!

He sorted the boolits for weight and checked final COL. He wouldn't let me slide with any more than .005 out!

He's a tough armory chief.

[pressonregardless]

Thanks for the update, hope you'll keep us posted when you work up loads with 3031.

[Jim]

Thanks for the update, hope you'll keep us posted when you work up loads with 3031.

Will do.