I didn't post on this because I've never had a recoil issue with .223/5/56mm.

The other night I was shooting and experience severe pain. I realized that I'd assumed a position where the rifle butt was squarely on my collar bone. There's no padding there and boy, that smarts.

OP, if you're still with us, you need to alter your shooting position/gun mount. The rifle butt needs to be on muscle tissue, not sensitive body parts.