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AR15 Optics

22 Nov 2012
@ 10:22 pm (GMT)

Andy Gilmore

Have just bought awesome AR15 STI . .223 Calibre and now need to decide on optics for it. I wish to be able to head shoot deer with it as it should be capable . Apparently the STI brand are super accurate and its getting a few mods. Has Gunworks suppressor Maximus already.
Thoughts and opinions on scope choices 300 mmtrs possibly max for rabbits etc but some close shooting in the open areas as well. Most will be off Bi Pod
I was thinking SIII Series 8-32x56 with MOA reticle but is this over doing it as it wont stretch out as far as that would permit. But then again how much is too much ?


25 Nov 2012
@ 03:04 pm (GMT)

Nathan Foster

Re: AR15 Optics
Hi Andy, one of the things you'll want to be careful of is bulking out the AR until it is so cumbersome that it defeats its design premise. If going the route of a varmint rifle with high zoom optics, a bolt action varmint rifle would be more effective.

On the AR, even a Bipod is pushing it for me, especially with the recoil of the action / mainspring which is enough to open groups up to 2.5 MOA in untrained/semi experienced hands off sand bags- without the extra jump induced from a bipod.

A 3.5-10 SIII Sightron would be nice atop your rifle for general work including neck shooting deer, but for varminting, I can see the need for higher zoom. A 32 power scope really is over the top for an AR, simply too much bulk. If you want to shoot rabbits with the rifle at ranges of around 300 yards, a 4-16 zoom will be the most effective and compact scope option with all the zoom you need. You may find that 300 yards is your limit if you are not hand loading (hand loading can be a bit of a problem if you cannot find spent brass). 300 meters may or may not be achievable depending on the accuracy of the rifle, yourself or available ammo. 300 yards is a very realistic max effective range to work to initially.

Remember what I have said about potential accuracy. Just because the rifle is a semi automatic, doesn't mean you have to bang off one shot per 5 seconds. Shoot the rifle as you would a bolt action. Take care with forend control, trigger control and follow through. Poor follow through will allow the main spring to jolt the rifle off center, ruining groups. Trigger control will be a big issue, so slow right bloody down!

I have seen so many semi auto rifles ruin shooters. A guy shoots off the first 2-3 shots slowly, gets an average group, then lets everything else fly in the hope that the final group will be (for want of a better term) a destructive cluster. If you want to take away one piece of advice, shoot slowly. Sure, later on you can have a burst and let it rip. But for today and for tomorrow, tell yourself to shoot slowly and surely. After many months shooting, there will be a day when you can walk shots or take multiple shots with great effect in the field. But that day is not today. With semi autos, many people try to run before they can walk and many will never see maturity of marksmanship.

If the rifle has a U.S contract guarantee of a certain level of accuracy, work to the the stated level of accuracy. If .75 MOA is stated, stay at the bench/range until .75MOA is achieved.

I know that you are wanting varmint level accuracy so my words are only reiterating what you already have in mind. Still, its good to go over these things and cement procedures. If you go to the range with a mate and then give him the rifle and he shoots it pop pop pop- take the bloody thing off him. Its not a friggin toy. You are doing the hard yards, he can too.

Anyway, that is all off topic, have a shop around for 4-16 power compact optics. I have used our own Sightrons with precision in bolt action rifles out to just over 1000 yards.



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