rimfire,
The 10" factory TC barrel should provide very good accuracy just as it comes out of the box. You could smooth it up a bit using some JB Bore Paste, per the instructions, if you desire. One thing I will say about the .44 Mag, from experience with a early octagonal barrel, the recoil will be severe compared to your 7-30 Waters. I can't speak for the 10" bull, as it is heavier than the barrel I had, but the recoil in the 10" octagonal was BRUTAL compared to a 8 3/8" M29 Classic hunter with the same ammunition. From a 10" T/C barrel, the 44 mag is a legitimate 125yd deer cartridge if you're triggerman enough to do it. If you are a hanloader, you will have better ammunition available, but this is the case with almost any centerfire round used for handgun hunting. If using factory ammunition, you should stick with at least 240gr ammunition that uses a bullet that is of heavy construction. The 10" TC provides a very signifigant increase in velocity over the common 6" revolver barrel, requiring bullets of good construction when close range shots are encountered.