I have shot a few hundred Calhoon 50 grain DblHP's, through a .223.
Terminal performance is quite spectacular, without pushing them too hard. Inside out gophers, pieces on the fence 20 feet away, kind of thing, if the shot alignment is right.
They are still sold around the gun show circuit. I gotta stock up!
The ones I have are made with jackets, not rimfire cases.
Cheers
Trev