Originally Posted by Hoppy74
7. What causes the bolt to rotate in the bolt carrier?
a) The bottom of the carrier key cams the rear end of the bolt and rotates it.
b) The expanding gas on the bolt face that comes directly from the gas chamber.
c) The cam-pin hitting the bolt carrier
d) The counter rotation of the barrel extension lug
The carrier key does not rotate in any way. Nor does it contact the bolt in any way. Those two facts make answer "A" impossible.
Gas chamber? Is that a part of the gun that I have not heard of yet? "B" is not the correct answer.
The barrel extension and the lugs therein are stationary, thus they DO NOT rotate. "D" is not the correct answer.
The cam pin must be in contact with the carrier for it to cam. But "HITTING" would be an exaggeration of the event (in my opinion).
"C" is the MOST correct answer if you ignore the odd ball wording.