I checked my x150 again and after firing 40 rounds with the 385 and 350 grain bullets theres nothing different. No cracks, scratchs or anything.
Mo archer, im thinking that theres a space between the stock and barrel lug and when its torqued down, the plastic flares and cracks it and when its shot, those cracks open more than more. Do not shoot it anymore, call cva and get a new stock, and in the mean time, im gonna run out to the shop and cut you 4 or 5 shims to put under the barrel legs on that kodiak's new stock, when it comes in. If its flaring like i think, it will leave a deep impression in the brass shims and then we can tackle this problem for sure. If the next stock does it, have them replace it with an optima. Or better yet, to solve your problem once and forall, a winchester x-150 lol. 4 years with this rifle and zero problems.