Bullet hanging up on front of chamber

I'm reloading 45 Raptor. I've noticed that sometimes the bullet will appear to load, but the gun is slightly out of battery. After extracting the round (which is usually stuck pretty hard), there is a ring around 1/3 of the bullet just ahead of the case mouth. It's not the rifling. This still occurs even if I drop the round in the chamber and them drop the bolt.

My best guess is undersized brass or an oversized chamber. Loaded brass is .476 at the mouth and .472 down the body. Fired brass is .474-.482 at the mouth, nonconcentric, and .477 mid body going up to .482 as you move back farther. That doesn't seem like enough wiggle room to do this.

Any ideas?

Edit: I believe the issue is solved now. Using a different powder I can seat the bullet deeper which provided a faster drop off in diameter closer to the case mouth. This provides more room to avoid hitting the lip in the chamber if the cartridge yaws. Also, I tuned the extractor and ejector (made them weaker) which could contribute to less force on the case. Probably not necessary to fix this issue, but beneficial in other ways too.