I fully admit that I am much better from a rest than I am off hand.
That said the best shooting handgun if you want to call it that is my Contender with the .223 AI barrel on it. It is fairly boring to shoot at 100yds unless you have a decent supply of flies to aim at, here is a 10shot group at 100,
The sad part of it is, if you want to call it that, is those aren't even handloads, they are from the Winchester White box 45gr .223 Varmint Pack ammo. They shoot so well I haven't even bothered to try and work up load for it yet.
With my revolvers I usually test loads from a rest when I am working them up, but once I find what I like it is only off hand from there. Since I hunt hogs with them all, from the GP-100's up through my 454 I only figure they are as good as I am. So why bother sitting behind a nice solid bench with a nice padded rest when it isn't available when I am out stomping around in the brush.
I DO have accuracy loads for them all with jacketed loads, but for the past two years I have been playing around with casting my own. As such I have been working with different alloy blends, and different bullet styles, trying to narrow down just what I want. I haven't nailed it down for all of them, but I do have some good candidates. With the 454 which is the first I cast for it is pretty much done, I haven't found anything, (really not even trying at this point) that will keep them together like this load below does.
Lee 452 300gr RF, Alloy straight clip on wheel weight, 1550fps at 25yds offhand from my 8.375" Raging Bull,
Score it how you like, but when I get 5 of those big slugs through a 1" or so square I call it good.
I can honestly say it holds them in tight like that out to further than I need to be shooting them. One of the last hogs I shot with it was trotting across the pasture from me at a lasered 87yards when I sent one through it's boiler works.