I've recently been playing with some 200 grain Beartooth gas checked bullets in the .357 Maximum. For mild, low noise loads I've been using 7, 8 and 9 grains of Unique with velocities around 1000-1300 fps. I always use a tuft of cotton or dacron filler with these small charges even though I know fillers are now out of fashion. Just for the heck of it I decided to try some Accurate Arms AA-5 powder because it measures much more consistently than does the flake powder like Unique. I decided to try the same charge weights with the AA-5. I charged five cases each with 7, 7.5 and 8 grains. Then I got a bit ahead of myself and realized I had seated bullets in the 7.0 grain cases without the filler. Oh well thinks I, I'll just evevated the muzzle before firing those and added the filler to the other loads.
Comes the shooting test, I elevate the muzzle, settle down on the target and CLICK. I remove the round, the primer is deeply indented but the bullet has not moved at all. Dud primer I guess, so I try another round, same click and no movement of the bullet. Now I'm confused. I've loaded rounds with no powder before and the primer always expelled the bullet from the case, but here they didn't even move. I clicked the remaining rounds with the muzzle pointed straight up and none even moved the bullet. I fired the other rounds, those with the filler and got fair accuracy and velocities similar to Unique with low extreme spreads.
On returning home I pulled the bullets from the misfires. The gas check was darkened with soot and when I upended the case out fell a little black disk. It seemes the AA-5 never ignited but melted or fused into a disk shape. One side of the disk was flat and smooth, as if it had formed against the gas check, while the other side was porus and lumpy. All five looked similar, just a disk of melted plastic looking stuff.
Filler may be out of fashion but it sure seems necessary with AA-5 powder in small charges.
