Re: .44Spl. bullet size
Miss Lilly: LOL. I hardly meant to imply that Ruger's are not capable of 1.5" groups at 25 yds and Lloyd said it much better than I apparently did.
It is just that I have found over the years that often the 'crush fit' of the Ruger barrel to the frame creates a 'obstruction' or a 'constriction' in the barrel that literally sizes down the cast bullet to the size of the obstruction/constriction and the slug then does not obdurate in the bore sufficiently to maximize the acuracy potential of the barrel. The cure for that is barrel-lapping or fire-lapping as per Veral Smith of LBT Bullets or Marshall Stanton of Beartooth Bullets.
The barrel/fire lapping process allows you to shoot cast bullets with the accuracy and (and often) better velocity than with jacketed bullets because of the reduced friction coefficient of a properly lapped barrel, and with lapped barrels I have easily shot, 1.5" groups at 25 yds. as Lloyd has provided (although he is a better shot than I am........).
While it is true, as the boss has said, that Ruger has improved its quality as well as maintianing the strength of its firearms over the years, you just might have one that needs a bit of TLC, as in lapping.
There is no reason you cannot get your Ruger to shoot better groups with cast slugs (and I prefer the Keith sytle swc of 240-250 gns in the 44) and save yourself the $ of expensive defensive ammo that may not perform as well as a hard cast flat nosed slug. Hope this helps and good luck.