Galil ACE dust cover repeatability and optics

[bsmithwins]

I was curious about the repeatability of the optics mounted on the dust cover of the Galil ACE 556 NATO rifle when it's removed for cleaning and replaced, so I decided to shoot some groups after removing and replacing the dust cover. Targets were shot at a known distance 200 yard range, optic used is a TA44 1.5x mounted in the dust cover, wind was light and steady.

Starting group (UL corner) was shot, and then the dust cover was removed and replaced, next group (UR) of 10 rounds shot, then third (LL), and fourth (LR)...

Running the groups through OnTarget I get these results, all numbers are in MOA:

Offsets are from the POA (center of the target), same POA was held for all groups and there were no adjustments to the scope. Spread is the max distance from CTC of the outermost holes, also in MOA.

Doing the math, the average difference in POI (POI shift) caused by removing the top cover and replacing it is 0.5MOA. Average group size is 3.3MOA.

I am planning on mounting an Aimpoint on the rail on the gas tube and repeating the test to check if that location is steadier/more repeatable for optics.

BSW

 

[Ryan]

Awesome! I always wondered how it affected zero. I'm interested in getting an Ace so this is good information.

 

[Leo99]

I'm confused about what you mean by dust cover. Isn't the dust cover that flap that goes over the bolt carriage area? The optics mount to the rail on top, no?

 

[bsmithwins]

Going by AK terminology, the upper piece of sheet steel with the optic rail and rear sight on it would be the dust cover.

I've been referring to the sliding part on the side of the receiver that covers the charging handle slot as the wobble plate, as it has no part that's comparable on an AK.

LK