I am thinking of going with Trijicon ACOG TA31RCO-M4CP for my LWRC M6A2.

http://www.militarywarfighter.com/Trijicon_TA31RCOM4CP_p/trijicon-ta31rco-m4cp.htm

 

I like its reticle pattern.

 

However my barrel is 14.7" and with the muzzle break its about 16". It's says on the website that is was calibrated for the M16M4 rifle with a 14.5”

 

Will I be safer to go with the TA31F that only specifies that it was calibrated for 5.56(.223 cal) flattop rifles????

Do you really think that .2" is going to make a difference? There are probably larger differences just caused by barrel manufacturing variations.

No I dont thinks so, but I am new to this and I am trying to understand some of it. So far from reading on the internet I get that you cant take the Trijicon Bullet Drop Compensation(BDC) too seriously because of different barrel manufacturing variations, sizes & ammo types and etc., but it will be very close.

im looking at the same thing for the same rifle i have the SPR

I ordered mine from optics planet.com Used coupon "opiv5of" to get 5% Off the entire order and they did not charge Tax.

Why did you choose the ta31? Seems a lot of people choose the ta11 over it. I like to hear what your thought are.

I went with TA31RCO because RCO has the killflash, better pauch/scopecoat that fits my mounted on top RMR as well, Lanyard attached adjustment caps. But the biggest thing for me was its unique reticle pattern and 4x magnification.