Glad to hear about your trigger time. Shame about that 10/22 takedown. I haven't even seen one yet, but I suspect extra barrels will come threaded for use with "muzzle accessories", as Ruger calls them. Considering their production capacity is already booked for the rest of the year, I might just grab the first 10/22 TD I see. I'm glad I did that to all three Rugers I bought (so far) this year. These models seem to trickle in slowly, if at all. Often, it's just the one in the rack that's left.
I got some Federal Champions from Midway, where currently they're on sale. I think I paid $1.89 a box, which is a steal for what is basically match-grade ammo. Midway's ordering page was a bit confusing. I wanted a brick, it said "$1.89 per box", so I put in the number "10". Then the other day this hugh box arrives from them, and inside were ten bricks of Champion for a total of $189 plus shipping. I missed the part on the page that said "sold in packages of 10 boxes".
This worked out better than I expected, because I now have about 14K rounds of just that one brand of ammo, with a very good expectation that I will find the perfect formula for each .22 I try it with. I suspect the CZs will be much less fussy than the 10/22, but I have a "sample pack" of one box of everything, just so I can follow where the results are pointing.
I'm also starting to test the Ely Rifle Match against the Champions. Right now, rather than resize them, I just segregated the ammo by rim thickness. I noticed better consistency in the Ely, with only two about-equal distributions of rim thickness, both .0005" apart. The Champion fell into four groups, with varying percentages, but again each group varying only .0005" from the next. The uncertainty of my measurements (me and my calipers) makes the fifth position to the right of the decimal dicey.
Until I do more testing, I only have hunches. I suspect the Ruger is vey finicky about what it likes, with .222" diameter bullets and the thinnest rim dimensions the best. The CZs, I can only guess that they will be happy with one particular bullet size, but that's only SWAG at this point.
Aaaaannnddd, I was able to sort the rim thickness of my Ely .17HM2 ammo into four about equal groups. Can't resize the bullets, but I can see how well the CZ 452 does with different rim size, especially since I now have the Timney trigger on it.
I could never afford to do this kind of research with centerfire ammo, especially match-grade ammunition. I've decided I need a thousand rounds of a particular brand of dimensional/weapon combinations to find the best, and still have about a brick left over for "productive" shooting. That means I'll have to double my inventory of subsonic test ammo. When I see things on sale.
Evening WinMag and Happy Easter - say, that last shipment should keep you supplied for the upcoming testing jamboree. Midway has some good prices but the combination of sales tax and shipping leaves me looking at other suppliers or usually a local source.