Back in the 1800's a lot of things were tried in order to increase bullet performance. The big heavy bullets used in the Sharps et al did a good job but wouldn't expand at the below 1600 fps most of them achieved. For a while it was popular to drill a hole in the big 45-and-over caliber bullets and stick either a 22 blank or a 22 short minus the bullet into the hole and try and get increased expansion thataway. Didn't work too well then, and don't see why it would work well now. Only time the 22 would go off is if bone was hit, and not always then, so the idea passed away into well deserved oblivion; at least as far as civilian sporting rounds went. Durned big ol' bullets didn't need to expand anyway, but people will do the craziest things........... the ol "what if" syndrome.