For years as a trial judge I carried a variety of handguns both on my person and in my propped-open briefcase on the bench. For screw-in-their-ear backup I carried either a Remington double or Colt Thuer, both in .41 rimfire. I'd stashed away several boxes of the fresh Navy Arms ammunition when it came out in the '80s till circa 2010. Am aware of the cartridge's limitations, but the Navy Arms stuff seems marginally hotter than earlier loadings...and better than nada. As an aside, kind folks are offering single rounds of this loading for up to $20.00 these days.