USPSA is the US version of the international IPSC. There are a few subtle differences between the two rulesets, but by and large they are the same. Easiest way to describe it is to watch a few USPSA videos on Youtube.
IDPA was a spin off of USPSA back in the mid-90’s when some people felt like USPSA strayed away from the roots of “practical shooting” and became a run-and-game and too much of an equipment race with some of their gun divisions (think Formula 1 vs Stock Car). IDPA stresses shooting more or less stock guns in simulated ”real life” scenarios with your gun and mags worn under a cover garment. The irony is IDPA got ‘gamed’ almost from the get go, with people shooting tricked out full size guns that very few people carry in real life and wearing silly photography vests as their cover garment, and the “real life“ scenarios are quite often a stretch (1 vs 6-9 bad guys). The few times of year I shoot IDPA I use it as practice for my EDC gun/gear and everyday street clothes.
Depending on where you live, there may be more USPSA or IDPA matches, some clubs offer both venues on different weekends. Check out Practiscore.com and do a search for matches near you.
Currently the Sig X5 Legion is the #1 gun used in USPSA Carry Optics division, with the Shadow 2 in #2 place. The Sig is a neat gun, and the extra weight of the tungsten infused grip helped get it to 40-ish oz which IMO is the sweet spot for a handgun. But I think the main reason for its popularity is it is ready-out-of-the box for either Production division (iron sights) or Carry Optics division with its plate mounting system for a red dot. But it still is a plastic gun, striker fired, and has had some teething issues in the first few years of its release. Grey Guns offers a pretty slick trigger job or parts for DIY. I’ve shot them, and they can be nice guns.
But if you are an all-metal and DA/SA fan, the Shadow 2 is hard to beat. At 46 oz it is weighty but all that weight, especially out front, makes for a pretty flat shooting gun. Until CZ started importing the Optics-Ready version the only recourse we had to mount a red dot was to send the slide off for milling to accept a red dot. As mentioned above, there’s good after-market support for the CZs for springs, parts, and accessories.
Currently the USPSA rulebook allows a max weight of 59 oz for a Production or Carry Optics pistol, so you can add even more weight to your gun if you like (tungsten guiderod, brass grips, lights, etc.). But one thing to remember, while weight helps to tame down recoil it also slows you down a little when transitioning to another target.
Here are my Shadow 2’s.
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