Yes, groove diameter of the barrel.Stamping on the barrel .455 I assume that’s diameter, but is the .760” the case length?
This borders on 'Sacrilege'. 250 pieces of brass is a starter set in many quarters.Last I looked Starline has it. Get the 250 box and easily sell off the extras.
It has happened. But I doubt with 250 45R.Extra brass! Ha ha! Thats funny! As if...
I would expand on this to say no revolver/pistol should be stressed pressure-wise. Rifles too! I admit to having mellowed some as I have aged. I can't see where fighting for that last 50-150 fps. of velocity ever made a difference in any game I have hunted. I admit to liking big bore handguns but will any critter know the difference when being hit with a 45Colt 285gr. SWC at 900 fps or 1200? A 44Mag at 1100-1200 or 1500? For sure this shooter knows the difference in recoil, muzzleblast, and more than likely weapon system wear and tear.Top-breaks shouldn't be stressed pressure-wise,