Here are the pertinent facts:
I'm new to the 300 whisper. I've got a 16" barrel with the gas port in the pistol position. I was playing around with really light loads seeing how quiet I could get it.
The load that I fired when the problem occured:
168gr BTHP speer "Hot core"
7 grains of 2400
CCI 400 primer
PMC brass
Most of my brass is lake city and winchester. PMC seemed to be within spec when I measured the necks before loading bullets.
I have an A2 stock with a carbine buffer spring and a rifle buffer with all the weights removed.
I had previously in the day fired the same loads with as little as 5 grains of 2400. It cycled fine and even locked back on empty. I had shot 30 plus rounds of the above load(with 7 grains of 2400) on a previous day with basically no problems. I'm having some magazine issues but I think that is unrelated.
2 questions:
Why did the bullet get stuck?
Why did the carrier key shear rather than just cycle?
I have my theories but I was hoping someone with more experience could help me understand this failure.
EDIT:
additional question: Whats the best way to get the bullet out? Pound it out? Shoot it out with a bulletless load? Should I pound it out from the back or the front? The bullet is stuck about 3" into the bore.