"what can be down to prevent it? "
Gonna have to quit carrying appendix or small of back, or learn to live with it.
I carry a full size 1911 IWB at the almost 3:00 o'clock position. No problems...
Beretta 92 in a hbe iwb 3:00 some times when i sit down in the vehicle or chair the muzzle pinches my butt cheek. May be between it and my wallet no sure on that
You might try a DeSandis 105 Kydex IWB holster. I've got one for my Glock 19 & 23 and my S&W 9mm. It is snug, but my Glock 21 will fit in the holster for the other Glocks.. but I may go ahead and get it its own holster in the right size. These holsters are extrmely comfortable.
The leather against the skin / underwear is so smooth that my jeans will slip down if my belt isn't hooked. I put a strip of velcro on the back so it would give me a little friction against my underwear. Approx. $49. Adjustable for cant and height. If your weapon happens not to fit as snug as you want... you can always put a pad of velcro [soft loop side] inside the holster.... works very well.
Beretta 92 in a hbe iwb 3:00 some times when i sit down in the vehicle or chair the muzzle pinches my butt cheek. May be between it and my wallet no sure on that
I carry full size 1911 in crossbreed super tuck at about 4:00 and works well. When I sit the muzzle will be pressing against the back of my pants leg/ pocket area and sometimes pushes into the seating surface, causing the whole holster to try to push up a little but my belt is tight enough that no drastic upward movement occurs. Baggy pants helps make more room for the muzzle while siting and more give for the any movement of holster while sitting. But never had my cheeks pinched