I purchased a new Browning X-bolt Western Hunter long range in 300 win mag 2 months ago and have been having issues with it ruining brass. The first case was a hand load of 67gr of IMR 4350 Hornady brass and 168gr amax and resulted in case head separation. I thought maybe the brass was getting close to its end of life so I ordered 100 new pieces of Peterson brass and reduced the load down to 65gr of IMR 4350 and 168gr amax and the brass stretched in the web area with the first firing. I ordered some factory ammo to try so I could eliminate my reloading as the problem and the factory loaded ammo is showing the same ring in the brass after 1 shot. I took the rifle to a gunsmith today who checked the head spacing with go- no go gauges and said the spacing was good. We contacted browning and they had not heard of these issues and wanted the rifle sent back to them. I'm just curious if anyone else has had problems like this with any rifles and what might cause it. I wasn't running hot loads and just not sure what would be causing the problem. The gun smith was kinda puzzled too. The casing on the right is the Hornady casing that failed. The 2 in the middle are new Peterson brass loaded with 65gr of IMR 4350 and the one on the left is the factory loaded round. Sorry it's kinda long winded.