For we they've been relatively "mild" calibers. Both had recoil pads with the consistency of hockey pucks and weighed under 8lbs.

.300 Weatherby with 220 gr. (factory)
.338 Winchester with 250 gr. (reload)

Both shot off the bench and oddly within a couple of weeks from each other. One was a friend's, the other an acquaintance at the range.

I've shot 9lb 375's with 270 gr boolits that were far easier to shoot than those two.