Elkins45
01-24-2016, 07:31 AM
I bought six bottles of this stuff ($18 for 500 grams, which is 1.1 pounds) when Graf's was having the free hazmat deal before Christmas. It was described as a granular powder, and that's as good a description as any. It is a light gray and the grains look like little irregular gravels. Other than Trail Boss it is just about the fluffiest stuff I have ever used.
It is listed as a shotgun powder and Nobel doesn't provide pistol data for it, but their burn chart lists the burn rate as being equivalent to AA#5. The only problem is that it is so fluffy that it takes up almost 2x the space. As an example: last night I loaded up some 357 Sig using 10.0 grains of AA#7. I wanted to do some test rounds with GM3 so I swapped powders. The same powder measure setting that dropped 10.0 of #7 dropped just a touch under 5 grains of GM3. There's not enough room in the case to reach what would even be the starting load weight for #5.
The upside is that this looks to be a great powder for tall, skinny 38 specials because it will be bulky enough that a double charge of even a light load will be obvious, and a correct load will be easy to see before seating a bullet on a progressive press.
It is listed as a shotgun powder and Nobel doesn't provide pistol data for it, but their burn chart lists the burn rate as being equivalent to AA#5. The only problem is that it is so fluffy that it takes up almost 2x the space. As an example: last night I loaded up some 357 Sig using 10.0 grains of AA#7. I wanted to do some test rounds with GM3 so I swapped powders. The same powder measure setting that dropped 10.0 of #7 dropped just a touch under 5 grains of GM3. There's not enough room in the case to reach what would even be the starting load weight for #5.
The upside is that this looks to be a great powder for tall, skinny 38 specials because it will be bulky enough that a double charge of even a light load will be obvious, and a correct load will be easy to see before seating a bullet on a progressive press.