I posted the article below in another thread, but here we go:
I did a 25 yard sandbag test with various types of ammo, five groups of five shots each:
CCI Mini-Mag 36gr HP held the tightest groups at 2" or less, no malfunctions.
CCI Mini-Mag 40gr solid point, 3" groups, no malfunctions.
Remington Golden 36gr HP, 4" groups, no malfunctions (this is the newest batch, with good primers)
Federal Champion 36gr HP, 6" groups, with about a quarter of them causing the slide to short cycle. The slide came back enough to eject the fired casing, but not enough to strip a new round from the magazine and chamber it. My daughter's Walther P-22 did the same thing, though my Ruger 22/45 didn't.
This tells me that the Federal are inconsistant, with some being weaker than others, hence the wide groups, short cycling slide and the empty casing only kicking out about a foot from the gun, as opposed to the other types kicking out 3-4 feet.
The group sizes averaged about the same in all 3 guns.
On another day, my shooting buddy brought along a chronograph and to no surprise the CCI Mini-Mag averaged about 30 FPS deviation, whereas the Federals averaged over an 80FPS deviation, sometimes over a 100.
I shoot Steel Challenge and a rimfire version of IDPA with my M&P22 and I need the best groups I can get, as a miss is a loss.