Re: US Optics #3 M40 elevation knob vs EREK 1/2 mo
M40 is just the style of the knob (scalloped edgeds as opposed to plain round knurled knobs) and can be had for #1's and #3's. Mulehunter you actually should have 26.25 moa per turn, as the #3's have 105 clicks per turn. #1's have 48, and Erek's have 90.
mattk-not all knobs have the usual lines. My ST10 with #3's only has a vertical "zero" line, but with 10.5 mils a turn its hard to get lost (nylon washers can be fitted under #3's to make zero stops too).