Last week I took my 308 NM to the range to try different load, 66 gr of IMR 4350 over 180 Sierra RN projectile. 4th shot all creation broke loose. Stock in 3 pieces, magazine blown out, extractor collar blown off the bolt and wedged the bolt. The load is the min recommendation per Lyman's book. Sam and Tom think that either bolt failed or a burst case. It is at the gunsmith's now. He said that he has seen this before when he worked at Hill Country. I will know shortly if the receiver is OK. I have one load left and will take it apart to check the powder and projectile.