Cowboy action shooting intrigues me (never done it and I don't know any of the rules/restrictions yet) and I've just ordered a 45 ACP pistol, so would like to consider a 45 revolver with cylinders for both 45 ACP and 45 Long for cowboy action at some point in the future. Is there any difference in accuracy from such a revolver when shooting one ammo or the other? Is there any restriction of having to use one and not the other?