Most of the airguns shown so far are great for honing your accuracy skills, but not so much muscle memory. But there are airguns with very authentic feel and action. I started out with a CO2 revolver that closely mimics the classic Smith & Wesson, even though it is labeled "Dan Wesson". It uses metal and plastic cartridges that hold a BB in the nose so you can practice loading, firing and reloading just like a real gun. It even comes with a speedloader.
Then I found "blowback" CO2 auto pistols. I bought a 1911 copy but there are others - Berettta, Walther, Sig, etc. These operate like a regular semi-automatic pistol with the slide being propelled back with each shot. The magazine that holds the CO2 and BBs fits in the butt just like the real gun and it even locks back on the last shot. It even field strips like a real 1911. Even though it says "Tanfoglio Witness" it is the closest copy I've seen to a GI 1911.
For historical arms there is a BB Luger with the toggle action. Again, it locks open on the last shot.
For full auto fun there is a copy of the Schnellfuerer, based on the Mauser Broomhandle. The bolt reciprocates just like the real thing but unfortunately it does
not lock open on the last shot, so it's easy to keep wasting CO2 if you're not paying attention. Then there is a Schofield and Colt Peacemaker (not pictured) and more. Lots of fun to be had.
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