I bought these to cock long gun frames, receivers and especially barrels when cleaning rods and the rubber is so soft they do a great job. However, I only had to clamp the barrel of the Ruger MK II tight enough to knock the rear sight out of the dovetail notch for rear sight replacement, and because the rubber on it is so soft, the barrel "rolled" farther than I actually went to clamp it down and even forget about trying to tap metal! So I had to get a set of 50 year old vise jaws that I always had at the store and the rubber is more like the rubber on a treadmill or a tire and is hard, hard, HARD. Would buy them again, but I'm still looking for a set whose rubber is really, really hard.