Bought one from Roy at Mountain Air. He used a 24" .25 barrel, some nicely done valve and transfer port work, a slightly lightened hammer, and a some other nice touches. Will shoot light (20-21gr.) pellets to 660-670fps and the big heavy Kodiak's (30.7gr) to 585fps...so it's a 22-23foot pound rifle. Roy does very nice work.
The muzzle device below is my own bit of ugliness....makes the barrel a good bit longer, but it's easily detached. Cutting the tube, inletting, and adding the Qb79 gas block is also my own bit of cobbling. Didn't change the performance, still shoots as fast and as well as it did before.
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Haven't done the official 50yard testing...have tested pellets at 20yards (haven't been able to get decent weather, a day off, and the .25 together in one place yet). Unofficially, from plinking small items at 45-55yards, it's probably going to be in the 3/4 - 1" class at 50yards.
One 20yard tests:
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.25 Qb certainly isn't going to be a great all-around rifle. Pellets cost too much and the trajectory isn't as flat as faster shooting rifles. Hunting is the one thing .25's do better, this one was set up to be my new tree squirrel hunter.