ACOG (TA31RCO-A4CP) on a 308?

[Jeepers]

Hello everyone!
This is my first time posting on this forum even though I have frequented many times in the past, so i hope this isn't a stupid question (wouldn't want to kill my rep straight out of the gate haha)

Ok so here it is, I have a TA31RCO-A4CP RCO on my Wilson UT-15 and i know that the reticle is set up for 556 leaving a 20'' bbl (yeah the wilson has a 16'' bbl but I couldn't pass up the deal on the scope)... but i just got a new 308 semi... with no glass... so now im sure you can see where the temptation is pullin me since I have an Aimpoint that i can throw on my wilson lol.

I was just wondering at what range the combination of the 2 would stop working and im having trouble finding any info on the two different rounds past 400 yards (I never claimed to be an uber mall gun guru ) but if the difference is much more then 3 or 4 inches i might just try to sell it and be out the couple extra bucks for a new scope set for 308...

any thought or opinions would be appreciated
happy shootin

 

[m4geryACOG]

I've got the RCO-M4 model. Something to consider is that the eye relief is only 1.5 inches. Depending on how you/your shoulder handles recoil, .308 might cause the scope to smack your eyebrow. About the difference in trajectory, not sure, but if you do an internet search for "jbm calculations," you should find a good online trajectory calculator (it's free).

I moved the RCO from my 16" carbine to my 20" barrel rifle, and am getting a slightly longer eye relief model ACOG for my carbine for that reason. (I'm not recoil sensitive, but my should "gives" a lot)