I worked up a decent load for the 129 Internbond which uses 50.0 H4831SC. Wanting a harder bullet for moose hunting, I wanted to use some 120 GMXs I had so I thought I'd load them with the same to try. Turned out they shot well with a few cases I had with standard primers in them. A few I loaded with Fed 215 opened up quite a bit. So I think the powder and charge are useful, but primers might be something to work with. The temps were hovering around "this public range is all yours" (or minus 30°) which is why I tried mags, but apparently they aren't necessary.

Last edited by Klikitarik; 01/11/20.

Sometimes, the air you 'let in'matters less than the air you 'let out'.