Don't shim the rings. If anything you want to shim the base. Shimming the rings will put them out of alignment and torque your scope, and will definitely put undue stresses on everything.
If you want to shoot really far with a .22, you'll want something along the lines of this adjustable rail: https://arcanglesolution.wordpress.com/2012/11/09/hom/. There are other, simpler designs available as well.
I use Burris Signiture Zee on a CZ Silhouette 22RF. The scope is a Bushnell 3200 Tactical 10X with 80 moa total erector. The rings put ~ another 20 moa into the system. This set up is good to 300+ yards.
Standard velocity works better at distance.
A friend of mine and myself have a wilderness lake we go to that has lots of stumps in the water at 200-600yds and is all swampy behind it. We laser range stumps and then try to hit them aiming at objects on shore. Most of the time you can't see what you are trying to hit in the scope. You can easily get back on target to see a miss, or not, at those ranges. I have always found it really amazing how accurate the .22 is at long range in calm conditions but throw in some variable winds and even 200yd targets are hard. We mostly use my FV-SR in a Boyds tacti-cool stock with a Bushnell 6-24x40 on it. I am thinking of upgrading to Signature Z rings with +10 or 20 inserts but I don't know what I would use for a zero then. My buddy got 9 out of 10 @ 478yds last fall on what we estimated to be a 12" stump after we had figured out the aiming point.
How do you like the stock? Think it was worth the purchase?
Considering one for when I pick up my FV-SR tomorrow
It's nice if all you are going to do is shoot from a bench. It's a little heavy for carting around IMO. They inlet them more than I think is necessary so there are a couple of weak points so get some DIP bottom metal if you do decide to get one. Some one on here was selling heavy gauge bottom metal also. Pillar bedding, I did it to mine, is even better but you still want the heavy bottom metal. You will also need the longer action screws, you can get those from Boyds when you order the stock.
Thanks for the info. I was able to get the FV-SR today and I think I will try out the factory stock with some sort of cheek riser first.
I will have my Vortex Diamondback 4-12 sometime next week, cant wait to start hitting my gong at 300 yards
Any muzzle devices worth looking for? (other than drooling over suppressors...)