I got this put together last week, or the week before. Finally got to shoot it some while we were working on getting our muzzleloaders set up for goats this month. Only ammo I've run thru it so far is Armscor, and Cci Minimags, and only 100-150rnds. Still tho quite happy with the accuracy, function and handling. I've still got the factory 24" .22lr and .17hmr barrels, but this will mostly be used in this configuration I think. Original config...both look the same. The .17hmr has little trouble keeping it's shots under moa, the factory .22 is more like a 2moa barrel. Ive actually shot 4 or 5 different types of ammo thru the factory, and best has been the federal Hunter Match. The .17 just cci green and FMJs. Now in heavy barrel config the .22lr is holding slightly over moa groups (if you ignore the fliers which I'm pretty sure I enduced with my reload and failure on the first shots both times), which I'm happy with. Shot from my pod with a sandbag. Cci Minimags 50yds, 10 shots, one reload in each group. Last 5 shots. As you can see from the last group, changing my poa without changing my position isn't really conducive to consistency. After that group i shot the last 20-30rnds at stuff on the berm. Zoomed out to 12x the Minimags land right on the point of the duplex making it really easy to connect. I don't think I missed anything, even looped a couple rounds over a rock and into a can that I'd knocked down the berm, to settle behind a couple big stones earlier. Now I'm wishing I had another bare 457/455 action to build the .17 barrel out with since I'm really happy with this configuration. Oh here are the first rounds thru the barrel after I got it (bought used, supposed to have had under 100rnds thru it) Armscor at 32yds Sighting. I was shooting at the yellow point. Fired one, then fired 2 into the same hole, corrected and aimed at the cluster for last two. Bullseye group shot by my buddy Ed, shots to the left are from trying to shoot the Armscor box target 10rnds two shooters. All in all super happy with this gun.