Once again I spent a whole day shooting my SRH. I'm not satisfied with it in terms of accuracy. For the ranges I feel comfortable with it, I can shoot it almost as well with open sights.
I have a 460 and 45-70 barrel for my encore. I need a set of grips, but I want to use it sometime this season. I'm worried about the 460's recoil. 15" barrel, how do the two compare? Will my Bushnell 2-6x hold up to the bump from these calibers?
I would go with the 460 no questions asked, but at 60$ a box it's hard to practice. How accurate is it when shooting the 454 casul or 45 LC? If I do my part, what groups should I be able to expect at 100 yards? Maybe my expectations are too high.
What's the workable distance with the 45-70? My max possible shooting distance is 130 yards. It's a clear shot and I will have a solid rest.
Next season I will be picking up a .308 or .243 barrel and go from there.
PS I also have a contender with a 223 barrel on it that's very accurate. It is legal to use .22 caliber for deer here in south Tx, but not sure how good an idea it is.
I'm not sure what you mean by "SRH" but I can answer some of your questions.

That's a 1.5 inch group from 200 yards with my scoped Encore handgun in 460 S&W Magnum so, there is potential for quite adequate accuracy. I'll have to say though, it was one of the harder cartridges to get good accuracy with that I've worked with.
If they're loaded to their full potential, both the 45-70 and the 460 will have pretty much the same recoil. You might be happier to get a braked barrel.
You may or may not get acceptable accuracy shooting 45 Colt or 454 Casull in your 460 S&W. If I were you, I would not shoot the shorter cartridges in your 460 chamber as they can cause erosion of the chamber in front of the cartridge case. I think it's better to use 460 cases and download them if you like though the accuracy probably won't be as good in the downloaded version.
The 460 S&W is quite hard on scopes. The reason S&W went with a gain twist barrel on their revolvers was to lessen stress on scopes. The Encore barrel is not a gain twist barrel as you probably know. If you expect your mount and scope to hold up and not move in the rings, I would recommend SSK Industries 4 ring T'SOB base/rings. One of the scopes I broke on mine was a Bushnell and they wouldn't honor their warranty so no more Bushnell scopes for me (that also applies to Tasco, Simmons and Millet scopes since they're also in the Bushnell family). I've also broken T/C "recoil proof" and Leupold 2.5-8X scopes with mine but those companies repaired or replaced the scopes with no hassle so I have no complaints with them.
I would say the practical shooting distance for the 45-70 is a little over 100 yards and that for the 460 S&W a bit over 200 yards.
I've taken several deer with .224 caliber centerfire cartridges including with a Contender in 222 Remington. If the bullet is placed properly, a 223 Remington will easily take a deer.