You're going to make me break out the tape measure, aren't you?
My front sight has 3 numerals on it, an 8, a 12, and a 0. There appears to be two dots coming out radially from the front sight post at 90 degrees relative to the two adjustment holes, but the one furthest out is a larger, more distinct dot than the inboard one. Does this mean I have a "2 dot" front sight?
With it screwed all the way down, the top of the post is 1.75" above the bore axis.
With the rear set at 200m (22" radius) and an Insight laser bore tool in the barrel, the point of aim is 3.4" above the bore axis at 27 feet. This means my sight axis is pointing AWAY from the bore axis! With the rear set at 600m (21" radius), the POA is 1.5" above the bore axis at 27 feet. This means the sight axis is at least pointing TOWARDS the bore axis as it should, but still way off. According to my ballistics calculator, with a 1.75" sight height, my sight axis should be 1.2" above the bore axis at 27 feet for a proper 200m zero.
To get the right 200m zero, I calculated that my sight line should point down towards the barrel axis at a .097 degree angle. When set at 200m, the sight line is pointing away from the barrel axis at a .292 degree angle, so I need a .389 degree correction. With a 22" sight radius, that comes out to 0.15" of correction. So I either need a rear sight that is 0.15" taller, a front that is 0.15" shorter (which would put the top down inside the gas block!!!), or a combination of both. I'd like to not have my front bottomed out, so if the L1A1 rear is more than 0.15" taller than what's on there now, I should be fine.
Uh, just how much taller is the aperture on a L1A1 than a standard metric rear sight???