I have two CZ 527 Varmint model 17 Hornets, the Varmint model comes with a 24in tube. My first one I had cut down to around 21.5 inches when it was in getting threaded and the second one is still close to 24. Shooting the exact same ammo, there is very little velocity difference between the two. I had my SS HB Bmag shortened up to 20 inches and it still shoots right at 3000fps with the 20's. Had one of my 17 HMR's shortened up to 20 from 22 and it seems to have actually picked up velocity, although it's kind of hard to tell if it's just the ammo because that stuff has such a variance in it.
The little 17 Hornet, like the 17 WSM, shoots so little powder as well as the powder you use in these things is fairly fast burning, it just doesn't take a whole lot of barrel length for them to still get nearly the same velocity as a longer tube.
Lets say you lost 100 fps, which you won't, shooting PD's at 150 and closer, you'll see zero difference, but, what you will notice is how much more convenient it is to shoot having a shorter barrel, especially if you're screwing a can on the end of it.
Also, I don't think those Savage Model 25's have a very large contour barrel on them so cutting it back a few inches will not only make it more rigid but it'll give you more shoulder for your suppressor to square up against.
Excellent choice on selecting a suppressor. The DA Mask is one of the best rimfire cans, that is also 17 Hornet rated, you can get. You'll love shooting your 17HH with a can on it. They're not very loud to begin with but you put a can on them and you'll giggle like a little girl every time you pull the trigger.
