I think you should go with the longer barrel. and I will tell you why.

IMO the 22 Hornet is one fantastic varmint cartridge for shots out to 200 yards(for ground hogs). The round is fantastic because it has enough OOMMMPPPHHHH to kill a hog at 200 yards. But the best part is that is is a very quiet round that has 200 yard efficacy.

I really like the fact that the Hornet is substantially more quiet. Now to the 24" barrel. You will notice a difference between the noise level of a 24" vs" a 20" barrel. I actually went to a 28" barrel for additional silencing. Trust me, it works. Just listen to the noise level of the rifles sitting side by side, you can tell the difference.

Personally I would not go to the K-Hornet. If I waned more powder capacity I would simply go to a 221 FireBall. Tom.