I'm new to precision rimfire. Background in center fire and hand load, so I collect a lot of numbers before dialing in.

Gear is RimX with a 20" 15T benchmark barrel

Learning a few things.

1. The barrel tuner makes a difference. Repeatable and reproducible. Seems dependent on the barrel and less dependent on the ammo.
   
2. These were all shot at 100 yards. Is this ~1MOA reasonable?
   
3. For PRS22 and NRL22, do you zero at 50 or zero at 100?
   
4. Anyone try the Biatholon stuff from Eley? Heard it might be better for colder weather.
   
5. Lubrication types don't like mixing. When I switch from one brand to the next with different lube without cleaning the barrel, the groups open up. I always clean the carbon ring as soon as it looks dirty but if I dont clean the barrel with a nylon brush and cleaning solution, I can really notice it in the groups.
   
6. Thumb support? Yea or nay?
   
7. I have an armageddon shmedium for a front bag rest, any ideas what a light "big bag" I can use as well?

Any guidance and experience would be helpful.

Caveat, I have tried to should 30-50 fouling rounds between switching ammo brands, its just not the same as cleaning the barrel.