For carbines I use one bag under the frame and one under the heel of the stock. I pinch the trigger and trigger guard with my thumb and forefinger, never touching the gun. For pistols, I bought an old grip, sliced the bottom off level with the plane of the barrel and attached it to a piece of 1" plywood that's 1' square. On each corner, I epoxied 5/8" hex nuts under through holes in the wood and used these along with bolts as levelers. This way, the barrel of my handguns don't touch anything and when I've worked up a load and zeroed it, I just switch grips.