CZ USA 457 At-One Varmint 22 Long Rifle Black Bolt Action Rifle - 16.5in - Using the popular Boyds AT-ONE stock as its basis, this 457 Varmint variant makes an ideal trainer. With the push of a button, length of pull can be adjusted from 12.5in to 14.25in. Comb height is similarly adjustable, with 5/8" of rise available. The stiff laminate stock provides a nice, rigid platform to work and the threaded heavy barrel makes fitting a suppressor easy. In addition to the receiver-mounted, push-to-fire safety, we chopped almost an inch of length from the action and slab-sided it to reduce its footprint and weight. With the exact same swappable barrel system as the 455 and the same reliable polymer magazine system, the 457 is without a doubt the best rimfire platform we've ever fielded.