Ever since ammo prices went through the roof, .22 caliber weapons have become the ballistic flavor of the day. Gunmakers have unleashed an entire arsenal of new .22 cal AR-style rifles. And now Smith & Wesson is launching a .22 M&P. Smith’s Walther division is building the M&P22, which has a 4.1″ barrel and an adjustable rear sight. The pistol’s single action-only Massachusetts 10-pound trigger will still suck (big time). Needless to say, Bay Staters and Californians will get a 10-round magazine. Everyone else holsters . . . 12. The Smith & Wesson M&P22 should be cheaper to run than your kid’s Christmas toys. In other words, it’s an excellent practice gun for owners who already holster a larger caliber M&P, and a good enough gun for self-defense practitioners who can’t cope with recoil who, sensibly enough, want a full-size (ish) gun.