I didn't see anything in the .32 caliber range on the H&R barrel replacement web page. The closest that I saw would be the .308 which would really give a LARGE range of possible loadings. They even have one in .30-06 and you could increase the range on the upper end a bit with that while still allowing you to shoot low velocity round balls at squirrels if you so desired. Personally, I would choose the .308 since the brass is easier to find instead of the .30-06. Besides, I already reload for .308, so I wouldn't have to buy any new dies or anything.