Carbine Basics: Irons, Optics or Red Dots?


Most carbine shooters run iron sights, a red dot, or a fixed magnified optic. A few months ago I headed to the range with a sample of each to see if one sighting system would offer an advantage over the other. Representative sampeles were a factory FSB and a CSAT rear in a Larue BUIS for the iron sight, a Trijicon ACOG MCRO for the fixed magnification optic, and an Aimpoint T1 4 MOA red dot.

To ensure an accurate representation of each optic, I shot a 50 shot five circle drill prior to shooting a par time 50 round course. Target is QIT-99, for the purposes of this exercise each hit counts for 2 points, hits in the two center boxes count as “x”.

Here are the results:

Iron sights (small aperture) 100-39X

First up iron sights. I ran a Larue BUIS with a standard A2 rear and the 0-2 aperture up.  I scored 100-39X.

ACOG 4X fixed, 98-40X

Next up, a Trijicon ACOG MRCO (Marine Rifle Combat Optic) with an M4 BDC.  I scored 98-40X.  I dropped one round at the 50 offhand.

T1 100-40X

Finally, an Aimpoint T1.This is a 4 MOA red dot that subtends 2 inches at 50.  I scored a 100-40X.

At the end of the day I didn’t notice a significant performance difference with any sight. Each had its advantages and disadvantages.At the ranges I was shooting, 50 yards and less, the irons and red dot were both noticeably faster then the MCRO.  The MCRO is a great optic, but clocked few thousandths of a second slower on each shot inside 25 yards.

Conclusion, I like my T1, but it is hard to beat iron sights for the money.

So how does a 4 MOA dot do at 200 yards, here is my zero target, this is the thrid group on the same target, 200 yards, prone unsupported, group is about 5″ or 2.5 MOA

200 Yards with a 4MOA dot