For 40 years hunting I used a fixed 3x Leupold Alaskan scope on my 338 meat getter, I prefer fixed power keep it simple stupid, light is right doctrine. I have 2 TA11 on 556 and 762 both with 16.25 barrels and absolutely love mine. I have LaRue QD mounts and I find no issues with eye relief, the same as most scopes I have. I also have 1-4x scopes. Variable scopes cause some sort of extra manipulation with my hand to adjust the power or turrets, ACOG nothing and I use the hold overs, OK my 1-4x scopes do not have true ranging ret and yes can keep them at a set power, but then why have variable power, glass clarity on Vortex and Leupold not in same league as ACOG to my eyes. my experience opinion is I prefer ACOG for certain applications. They are not precision optics, the chevron is OK but still not ideal as a thin cross hard. I had a 1-4x first on the 762 below befor I got ACOG and if I wanted to shoot groups then yes a 1-4x is preferred. I have banged steel out to 600 yards with my 762 using ACOG, the hold over marks are close to M118 but not true accurate but rounds down range I figured this out. To me faster than my 1-4x scopes for holder overs. I ran a couple course drills with my 556 and ACOG down to around 10 yards on B27 targets, not ideal at all, a simple red dot I prefer better and was a quicker through the drills but ACOG did work ok for me in this application and is more ideal for me past 50 yards. I ran some house clearing drills with my ACOG, works best occluded with a cap on. Outside in sunlight, the fiber tube will wash out the ret, we used tape on them to dim them down some. This is the good ole USA, its your coin, you want it so get the ACOG. I would suggest 556, I have shot my 556 with ACOG out there a little but I rarely go past 200 yards with it and ACOG but at 50 - 300 yards, 556 and ACOG is ideal for me, it works, is rugged and simple.
7.62 wth ACOG and bipod, now sports BCM vert grip, no bipod.
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100 yard steel with 762 and ACOG above
First day out with the 762 above using 1-4x sighting zero in 100 yards, my first 3 shots bottom left, quick adjust and good to go. It is much easier to dissect targets for groups with an actual scope Vs ACOG.
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