So, a lot of the "tactical" scopes come caliberated for a 223 BDC. Usually 55gr. Now you can use it with any caliber/weight but you will need to compensate for your compensator.

A couple of the scope companies will make a custom one for you that you can swap out. Much easier, especially if you have a favorite load. Leupold and Vortex come to mind.

I am considering an MK AR (1.5-4 or 3-9) and was curious how much it would. Not finding the price on the website I emailed them. The next day I received a price quote of $59.99 + tax. Not bad!

In case you were wondering it would be for a SSA (Silver State Armory) 6.8 SPC 110gr Sierra Pro SP load.