I thought 10mm was nothing when I was shooting some factory ammo. It was about five years ago when I got my g29.4. Guy also had a box of 175gr Silvertips that he had bought when he bought the g29.4 in the late 90s. I loaded those up, waiting for my turn to shoot. I thought the gun had Kaboomed! Two people to the left and right of me on the firing line looked at me thinking the same thing. They loaded them warm back in the day!