03-22-2012, 05:39 PM
(This post was last modified: 04-27-2012, 12:46 PM by txgunner00.)
Rambozo Wrote:H322 is a great powder. It's my favorite, but it's fairly fast burning, and you will likely run into load density problems and port pressure problems. In my experience, the powder isn't very temp sensitive. It's a Hodgdon "extreme" powder.
Personally, I would look at slower burning powders, maybe even something that would be used in a heavy magnum cartridge. I'm sure you can find something that offers a good fill, low velocity, and slow enough burning for port pressure. at the same time though, I have heard of secondary pressure spikes due to using too slow of a powder relative to projectile weight. I don't know how much of an issue that would be with lapua 144s and the 6.5 bore volume of the grendel though.
anyway, just some thoughts.
I have tried few slower powders and they were definitely not the way to go in this application. They would not produce enough pressure to burn all the granules and I had unburnt powder stuck to the neck and shoulders of the case. Even a Federal large rifle magnum match primer couldn't light them off quick enough.
I can't remember which powders I tried exactly but I think they were US869 and H4831