I decided to release this data in a thread rather than "review" style format because I wanted to get some good discussion going about it. Last night I spent from 5pm to 10pm testing 28 different kinds of rimfire ammo. I fired right at 700 rounds during that time frame, and recorded the data from each shot fired. Target - PR dot drill, 1/2" dots, 35yds. Rifle - Remington 40X 22LR This rifle is the most accurate 22lr I've ever owned. Based on my research, it is actually one of the rifles used in the PanAm games by the airforce smallbore team. Chronograph - PVM-21, 10ft out. Course of fire - Shoot 15rnds to season the bore to the ammo and rough zero, then fire 10rnds for group measurement. All rounds were fired through the chronograph. I intentionally tried to zero high of aiming point to keep the same aiming reference each time. The bore was cleaned after each 25 shot string, so the bore was in the same condition for each new ammo tested. The chronograph was outside, and I was shooting off my dining room table with the window open. Obviously this isn't the best shooting platform in the world. There was mirage as a result of heat escaping from my window, as well as the table being a bit wobbly what with using a bipod and rear bag for support. However, pure accuracy wasn't the primary goal of this test. I wanted to see which types of ammo produced the most consistent numbers. Results - Sorted by Extreme Spread Results - Sorted by Group Size This will be a continual thread. The next step is to choose one type of ammo, and then test it extensively through several different rifles being fired by several different shooters from much better firing positions. The core goal in mind will be to determine what ammo has great accuracy potential in most rifles, and which ammo is useless fodder. I'll hold back my observations for now. Lets get the conversation started! What do you guys think about what you see?