something I have done that has considerably improved my concentration when shooting the bigger revolvers, rifles, and pistols that I play with. With revolvers it has proven especially useful since the recoil is not the problem, I usually shoot large revolvers, I use a set of regular foam style earplugs in addition to the best quality non-electronic ear muffs that I can find. I discovered that my problem was related to noise and not recoil when I was working loads up for my .340 Weatherby rifle that has a muzzle brake installed. After 15-20 shots, my shooting went to heck. I observed over a couple of sessions that my shoulder was never sore, the scope never hit me, but the shooting deteriorated none the less. This may not help, but I think it is an often overlooked element in the equation. This has proven to enhance my performance with all types of rifles and handguns, especially if being fired on an indoor range. I use both plugs and muffs now when doing ANY bench testing, as well as for most shooting in general excepting shotguns.
As far as bench shooting is concerned, it's my belief that for the average handgun shooter/hunter, the practice of offhand shooting will make a world more difference than the bench testing. I practice offhand mostly because it is my belief that if you can shoot offhand well, you'll be pretty well off if there is any additional support available. I realize that you get peace of mind with a ragged hole at 25yds from a bench tested load, but the practice offhand will do you a world more good confidence-wise than a one hole group with a open sight revolver. I value a 5 of 6 shot group at 25yds standing where the shots are touching, or close, far more than all six shots in a ragged hole off the bench. I understand that you need a load that will do it in the first place, but most full power loads with a good cast bullet will do that from a quality revolver. In most revolvers of good quality you can get groups in the area of 1" at 25yds with the reccomended "Keith" load and the Lyman 429421(I'm going from memory here, always dangerous) bullet if it is cast by a good source. Just be sure to adjust that load for the current lots of 2400. I think there is an article that outlines the current load levels in Handloader this month, but there are many sources.