I took my lovely new weapon out for the first time & put about 200 rounds through it. Damned if my hand didn't get tired, I was planning on going through 400 rounds. I developed a lovely blister on the top part of my thumb where it meets the bottom of the slide. Is this normal since I'm a new handgun owner & what can I do to avoid this in the future? My thoughts would be to keep on shooting & toughen up the skin. I would greatly appreciate & welcome any & all comments.