Aimpoint QRP and QRP 2 question

[trooper84]

Quick question regarding the Aimpoint QRP and QRP 2 mounts... Are both absolute co witness or is the 2 a lower 1/3rd co witness? Both mounts have the spacers in them. I have the option of either with a used ML3 and would like a lower 1/3rd mount

[JSantoro]

Both are the same in terms of measurement. If I remember correctly, both can be made absolute with this spacer: http://swfa.com/Aimpoint-Spacer-Rail...er-P42367.aspx

Is that the spacer you're referring to?

For lower-third, you're gonna want to go with an aftermarket mount made for it. Again, if I remember right, there's a base-spacer in addition to the above, but it puts the optic in some kinda weird in-between; I'm utterly open to correction on that, since I've always considered QRP and other ratcheting mounts as only marginally capable.