Yes I shoot the 250 grain Barnes Expanders in my .50 caliber Wolverine II. And they do fit tight, although they go down without too much effort.

The accuracy from them are hard to describe. I have a RED DOT on my Wolverine and this target was testing the RED DOT and the Barnes Expanders. I changed the 3MOA dot to the + lens and it threw one of the shots off, but I am more then pleased with the little rifle. You might also notice, I do not push them as hard as some do, but I think I could push them a little harder. In the Black Diamond XR I pushed the Barnes Expanders to 120 grains and they still held true.....