I know exactly what you mean! The first time I shot my husband's rifle it looked like somebody was abusing me! You have to get used to how to hold the gun, but the recoil can always make that spot tender. My husband recently sighted his rifle in for deer season, and even he came home complaining of a hurting shoulder. My advice is to avoid what feels instinctive and not try to hold the rifle or shotgun off your shoulder. Jam that butt right into your shoulder and hold it there tight! Not only will your body help stabilize the gun, but it will help absorb some of the recoil. That's what I have done and I haven't been nearly as sore, nor have I ended up covered in bruises. Just don't jam your eye up against the scope, because you WILL end up with a shiner!
Hope this helps!
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