Im not the most technical shooter, but I can prove this article is BS rather easily. Drop a modern shell into your classic double (assuming it is safe to shoot) and pull the trigger. Doesnt feel very good, does it? Now, drop in a low pressure RST shell. Feels sweet, doesnt it? Its that simple. One feels like crap. The other does not. The rule I follow is this, I shoot an old gun with the closest thing to the ammo it was made to shoot. The end.
Pressure has very little to do with recoil. The major factors are shot charge and velocity. An RST shell may very well "feel" better (lower recoil) than a "modern" shell from Win/Rem/Fed. But if it does, it's because the RST shell has a lighter shot charge and/or lower velocity than the "modern" shell.
RST makes a great 2 3/4" 12ga pheasant load: 1 1/4 oz 5 or 6 shot, 1200 fps. Modest recoil for a 1 1/4 oz load, and it will stone any rooster that's not wearing Kevlar. Somebody decides that more velocity is better and selects the "modern" 1400 fps 1 1/4 oz load. He'll know the difference right away, because that extra 200 fps velocity--which doesn't make any significant difference to the pheasant--just increased recoil energy from 26 to 38 ft-lbs. Close to 50% more recoil. I don't even want to think about the 1500 fps loads!
