This scope already includes 3/8 inch dovetail rings and scope caps in the box, which are designed to fit the dovetail groove found on rimfires like the Browning BL-22, so you should not need to buy any additional mounting hardware.
No, the Barska AC10380 scope included 3/8″ dovetail rings are not compatible with the rifle’s 11 mm dovetail rail. The supplied rings may not secure properly.
The scope rings are made of aluminum alloy.
If your Ruger 10/22 has a 3/8 dovetail rail then this will fit. If you do not have a dovetail rail then you would need to purchase a picatinny rail for the 10/22, and 1" picatinny scope rings (low height).
This Barska 3-9x32 Plinker-22 Rifle Scope is designed to be used with .22 cal rifles and not 5.56/.223. I would recommend using a scope that is rated for the AR15 platform. Email us at Techsales@opticsplanet.com for assistance in finding a scope and ring setup that works for you.
I have one mounted on a dovetail presently, it came with dovetail mounts in the box
The manufacturer provides no information regarding the reticle. You would need to reach out to them directly to see if they can provide subtension information for the reticle.
Unfortunately the manufacturer has two different pictures listed for this riflescope, one with no diopter and one with a diopter. From research found online, this scope should have an eyepiece diopter.