As a new Aw93 owner i know exactly where your coming from, the problem is most american 22 rimfire that ive tried have tolerances that run on the big size compared with most made overseas. After much research, ive found there is 3 options, first is to shoot non usa made ammo, all ive tried works fine from the cheap eley sport basically its aguila and made in Mexico, SK pistol match, standard plus, wolf match or match extra and most eley,& lapua. I have settled on SK pistol match (not pistol match special) the second option is to simply measure your bullets, use a digital caliper set on MM and measure the driving band just above the case mouth, my gun will shoot any that read 5.7mm and less, 5.71mm will slide in the chamber but takes a light push to seat, 5.72 will not chamber
completely and will cause a alibi. I have a few cases of federal 711b and it is very accurate, but out of every 50 rd box i will have 5-15 that are above the 5.7mm size, if i sort them by measuring, then i have no problems, but it takes about 20 minutes to sort thru several boxes to get a 100 round match pak ready. The 3rd option is to have the bore lightly reamed, and pray it still remains accurate. Not a option im willing to do. My choice is to pony up the bucks and shoot the better ammo or measure my federal. Your barrel could be different, take some rounds and drop them in your barrel, find the ones that just fit and measure, then sort out all that are bigger is the cheapest solution. Hope this helps, David