Your going to have to start messing with load, choke combos. if you want to spring the big bucks, and in the long run save some big bucks because all the other stuff wont beat nitrocompany.com triplex load in hevi. you will be able to exstend the killing range on you and your dads guns for sure.im willing to bet it will tripple the pellet holes in a 10 inch cir at 40 yards. they will recomend a rhino or a jellyhead tube, jellyheads are cheap, you can buy one and try it out on both guns. shorter barrels dont shoot as tight as some of the still shoot 30" barrels , and you will loose some velocity, but they can be made into deadly killers,I have a few short barrel rems that can cleanly killat exstended ranges,so dont give up .it takes a little work i hope this helps------