Its jam o matic... The problem is the brass is way to thin meaning it folds in half when pushed by a bolt. Just compare fired 22 brass and you will see a big diffrence in thickness and strength of the brass. Its a round that you can fold over with your pinky only...
I used to shoot winchester ammo only but the quality went way way down its garbage now. Even the bigger rounds have problems. Americain egale 308 win jams allot too in anything I put it in its heavy loads then light and it won't cycle the bolt. Ammo is hit and miss it seems.