Ohio Varmint Shooter said:
Other than CCI..what is considered the best Standard Velocity round?
The answer is; the one that shoots the best out of your firearm.
If possible, what I would do is;
a. Buy a 50-round box of all the different manufactures you can/want.
b. Clean your rifle/pistol thoroughly.
c. Pick a distance (50 yards min, especially if test day has any breeze)
c. Shoot 15 fouling shots.
d. Shoot one 10 round string, followed by a second 10 shot string. If results are satisfactory, shoot another 10-shot string just to make sure it wasn't a fluke.
e. Th roughly clean the rifle and repeat for each brand/type of ammo.
Rimfires are like any other gun, some like Brand-A, while others like Brand-B and so on.
Once you find the one you like buy as much of that brand/LOT # you feel you'll want/need. If it's an auto loader, make sure it will function.
For my S & W model 41, the Wolf Match Target, Match Extra and Eley TENEX all shot the same at 50 yards. CCI Std Vel, Green-Tag and Yellow Box PMC Target were next. Federal just wouldn't function nor shoot worth a hoot. My pistol had a DOT scope so sighting was pretty consistent.
HTH,
Jim