I dropped the 40 for a decade or so to simplify things but realized that since I'm already loading and casting for 10mm a 40 makes sense too. A few years back there were some awesome deals on 40s and 40 ammo. I picked up Winchester police ranger t 180g, basically black talon, for $15.99/50. My only regret is only buying two cases. That led to me buying a S&w m&p compact 40 that I love and then a glock 22 mint gen 3 for only $229 that stays in my truck. I also got a deal on an FNx I believe that shoots great.
Casting again has brought me back to liking a flat nose on a solid bullet which most 40 stuff comes with automatically. Also loading with Longshot let's me take 180g 40 loads to 1150fps. Given the flat nose bigger diameter and extra weight I feel better with a 40 in the woods than a 9mm. I still like my 9mm 365 for daily carry but for mixed woods use like my truck pistol you'll usually find me with a 40 or a 10mm if not a 44 revolver.
I really want to stock up on once fired 40 brass while it's still available cheap. I think it's fading and my normal once fired brass source hadn't had any in a few years. I'd also like a kkm 40 barrel for my xdm 10mm like the one I have for a glock 20. It allowed me to seat heavier bullets to 10 mm length in 40 brass and run them at 10mm speeds. Bought a bunch of 40 brass for 2 cents each and only loaded them once and didn't worry about picking up brass.
