I have the aspherical 3.8-12X44 AO Intensity scope, bought from Natchez Shooters Supply about 5 months ago. Sportsman guide had this model Intensity scope, but now sold out. A fellow shooter at range, who pretty much only uses Leopold/Nikon brand scopes, asked to look thru the lens of this scope. He'd noticed a Natchez ad and needed a low priced scope for a centerfire rifle he didn't want to put a Leopold/Nikon on. He was impressed with the optics on my scope and thought there was nothing cheap looking about the scope. I've had my Intensity on either a 6.5 Swede mauser sporter or a .257 Roberts rifle since buying it. Probably over a couple of hundred rounds fired in these rifles with scope. NO problems whatsoever. Very pleased with it. Happen to own a 43 Spanish 1879 Argentine rolling block and for my 370 gr cast bullet loads I've referred to trapdoor 45-70 load data a few times for my reloads in the past. Based on recoil of my rolling block, don't think you should have a recoil problem with the Intensity. However, not sure about a modern rifle in 45-70, with their stouter loads.