I am not aware of what red dot you are using, the PM400 does not ring a bell.
I run an AimPoint T1, the dot rests squarely on the tip of the front sight post.
I believe you would need a shorter mount......link for the mount?
I have a Colt Match Target H-bar and Bushmaster XM15 "Dissipator" in this configuration.
Bought back in the day before shaved gas blocks or removable front sights were even thought of.
It's not a problem to get a scope mount and rings set up so that the scope bore axis is in-line with the front site post, or higher. The front sight is not visible in the scope unless using very low magnification.
Last edit: 10 years 3 months ago by JRH_ArmaLiteAR10T. Reason: Add or higher
JRH_ArmaLiteAR10T wrote: I have a Colt Match Target H-bar and Bushmaster XM15 "Dissipator" in this configuration.
Bought back in the day before shaved gas blocks or removable front sights were even thought of.
It's not a problem to get a scope mount and rings set up so that the scope bore axis is in-line with the front site post, or higher. The front sight is not visible in the scope unless using very low magnification.
Have the same Colt and made it into a flat top. I do not even notice the front sight post through the scope.
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