What distance were you testing this ammo? I'm assuming 50 yards (or meters) because it seems like EVERYONE tests at 50 yards. Since I use the .22 LR for silhouettes I must test out to 100 yards to see what is happening at the ram line and for shoot off chickens. It seems to me that MANY different kinds of ammo will shoot VERY well from any of my Contender barrels out to 50 yards. However, it seems like the high velocity ammo's accuracy really falls off at further ranges (I know...not always, that's why it is important to do your own testing).
My case was made perfectly by a .22 LR match barrel that I have. It would shoot some AMAZING groups at 50 yards with cheap ammo...American Eagle 38gr HP (<.25" @ 50), but when I tried to get it to group at 100 the best it would do is about 1.5" (or was it 2"?). Unfortunately I tried several flavors of match ammo and none grouped well enough for me to be pleased.
I have had very good luck with CCI Green Tag, Wolf Match Extra, Eley Pistol Standard (also it's twin...brown box Standard). I have other stuff that may work better in some barrels, but I just haven't tested enough to tell. It is a time consuming process and sometimes it makes sense to compromise a little if the ammo will perform adequately.
Just last night I performed a little uniformity testing of standard velocity ammo in my possession. This certainly wasn't a real scientific test, but it was enough to satisfy my curiosity. I weighed 5 rounds of various types of match ammo. My findings were that Eley & RWS (Dynamit Noble) tended to be the most consistent in terms of overall cartridge weight. I was a little disappointed by Wolf Match Target and Lapua Super Club because I found an extreme spread of about .6 grains in the 5 randomly selected cartridges. Please note that I only tested target ammo on the "lower" end of the price scale (<$4/50) with the exception of Eley Match EPS (which did indeed prove to be very consistent). I think that I will be testing some of the more expensive stuff that I have (Lapua Midas & Lapua Master). Well enough rambling for now...
I hope that I didn't cloud the issue too much for you!