Coming late to the game, the only ammo I have ever tried to weight and sort was about 2 bricks of CCI CB shorts for one specific rifle that I pretty much use for the 50 yd offhand matches and practice.  I have found that it is productive.   

Over the years I have shot several cases of Wolf, one case of discontinued Lapua (mostly for the 100 yard mini-hudson) and about half a case of Fiocchi. 
While I have used several different 22 rifles, my evaluation has mostly been based on performance out of a very heavy barreled custom Ruger #1 with a 24x Redfield shooting off a good solid benchrest @ 200 yards over several years.  
  With the Wolf I started with the lower grade.  In the rare dead calm or mild steady cross wind conditions  @ Etna Green  I typically got a strip-like group about an inch and a half wide and 6 to 8 inches long. 
Basically I attribute that to velocity variations. It got so I could listen to the sound of the shot and pretty well call the shot based on that.   When I switched to the mid-grade the vertical dispersion was cut in half or better and horizontal was reduced slightly.  I suspect that making the time and effort to weigh/sort might have been productive.
  I tried some of the top grade and there might have been an additional slight improvement. but given the normal shooting conditions I did not see enough to justify the additional cost.

I switched to the Fiocchi M, and then SM, ammo, generally buying it by the brick when I could find it.   My 200 yard groups switched from vertical to circular ones with scores in the 240s @ 200 usually with 23s balanced with a couple 25s shot in match conditions.
Then the 22 rf ammo panic hit and match grade ammo of any kind disappeared along with the rest.  

We have just about reached the point where "them what's got, wins" .   Unless we have been able to buy and stock up in years past, I fear we'll be pretty much stuck with buying whatever we can, when we can and weighing, measuring, and sort.

My bowl of Fed Auto Match are sorted to 51.5, 51.6, and a third bottle of about 40-50 rounds that fell outside.   I had the idea that it might do for silhouette, but it shot 2"+ groups at 50 so I relegated it.   

Interesting that we get such different weight variance results with Wolf.  I still weigh it, and cull the outliers for warmup ammo.

an once you find it, and save up for a case of it, you'll find that its been discontinued d