Thank you for that!Bartlett’s has IMR 7383. Supposed to be comparable to 4831. It’s surplus but it is new powder. You can read the description on line here.
From online description:
“ IMR7383 This is a slow burning stick powder originally used for the Cal. .50
M48A2 Spotter/Tracer round. This is not the same case as that known as
the .50 Browning Machine Gun cartridge. This powder is NOT recommended
for the .50 BMG round. It is a very bulky, single-based powder, composed
of 85% nitrocellulose and 15% stabilizers, flash inhibitors and graphite;
that was developed to replace the IMR4831 powder that had being used.
It has about the same propellant energy as IMR4831 when compared in equal
volume. IMR4831 data can be used. Begin with starting loads, reduced 15%
This is new powder, not pulldown.