Dunno about in an encore, but I have a win 94 trapper with a barrel only 1" longer than your gun, and I've killed several deer and hogs with it. I'd say accuracy would be your limiting factor with this cartridge, not power. This caliber kills by virtue of it's large diameter and retained momentum. High velocity will only flatten your trajectory, it will not increase killing power. Find a load your gun likes, and know your own limits.
Unless you want to run JHP's at over 1200 fps expansion can be iffy. I get my best results with cast bullets. A 250 grain SWC going 1000 fps or so will whistle right through a deer like he wasn't there. My normal hunting load is 18.5 grains of 2400 under either a 255 grain rnfp(1450fps) or a 320 grain wfngc.(1400fps) If you don't cast your own, look for a cast bullet with as wide and flat a nose as you can find. The flat noses really transfer energy well, and produce great wound channels. I've found that I seem to get game on the ground quicker with cast bullets if I try to place my shot through the vitals in such a line that it will break the offside shoulder on exiting. This tends to produce quicker kills for me. My farthest kill with this caliber to date is 80 yards. I feel completely comfortable out to 150 with it, given a set shot and time to get a good steady rest. I just seem to kill stuff a heck of a lot closer than that when I carry this rifle.