1x4 Optics Placement: Fore or Aft?

LowLead

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Good evening,

After reading threads about range time today, I thought I should throw my own in.. First off, I am pleased to have recently joined the AR club by acquiring one, considering how the last federal election went. I put a few hundred rounds downrange today, from 25 meters to 500 meters and overall I am very impressed with it.

And its a lot of fun!

So, I thought I would request comment on the opinion / knowledge of you folks with more experience than I, what would be the preference or proper way to place a 1x4 optic on an AR. I did come several of my own conclusions for advantages and disadvantages, see below: (I got the memo about how this is worthless without photos)

Forward Placement:

-Seemed to come up to the eye / target quicker at 1X
-Eye relief at 1X was sufficient, easy to keep both eyes open
-A little more forward heavy.. Hardly noticeable.
-At increased magnification eye relief was almost too far, really had to lean into it..




Aft Placement:

-Eye relief at all magnification was decent
-Rifle balanced a little better
-Felt a bit slower on reticle - target acquisition



This target was shot from prone with a bipod and bag, from 25 meters with the scope aft. 5 shot group. The other shots were aimed off hand at the rest of the targets on the sheet, less leg days and more arm / shoulders / chest days apparently...:eek:



I did get this rifle for the purpose of learning CQB - 3 gun stuff, so I am leaning towards having it forward. But, any good info from you folks with more experience is always appreciated!

And I like my new rifle.
 
Have a look at other setups and you'll see that usually the ocular lens of the scope is sitting over or close to the charging handle. This gives you the proper eye relief when using a cantilever mount, on a standard upper.

Usually eye relief is around 3.5-4" unless your scope is EER. What kind of scope is it?

My opinion is your scope in both examples is to far ahead. You want to be able to raise the rifle to your eye without leaning into it and be able to use the scope at any magnification. You want to do this the same way every time to avoid parallax error, sitting, prone or standing.
 
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There you go. Just like any other rifle. Here's it's on a good Ol Colt 6920. Shoots like a dream. You shouldn't have to creep forward to your scope. When you hit natural cheek weld you should be at the right spot.
 
Move the scope back as far as needed to get correct eye relief in a comfortable shooting position. If you have to ditch the iron sights to get it in the right spot do it since you will probably never use them since you bought a quality optic that you can be 99% sure won't fail you.
 
Extend/collapse your stock to your proper length. Set the scope to 4x since that's where your shortest eye relief will be for that optic and snug it down on the rail just so that it doesn't fall off, you'll be moving it around a few times.

Close your eyes, shoulder the rifle with a good cheek rest. Open you eyes and look down the scope. Is the sight image clear with even dark ring around the sight picture? No? Move the optic further away or closer as needed. Close your eyes and repeat. You will probably end up with the optic sitting right over your charging handle.
 
Extend/collapse your stock to your proper length. Set the scope to 4x since that's where your shortest eye relief will be for that optic and snug it down on the rail just so that it doesn't fall off, you'll be moving it around a few times.

Close your eyes, shoulder the rifle with a good cheek rest. Open you eyes and look down the scope. Is the sight image clear with even dark ring around the sight picture? No? Move the optic further away or closer as needed. Close your eyes and repeat. You will probably end up with the optic sitting right over your charging handle.

That'll do it.
 
Perfect, Thanks for the good tips.. the scope is on an ADM mount, so it's not difficult for me to move around. It's a Trijicon Accupoint 1x4, and so far it's pretty awesome. I knew I could count on you guys..:cheers:
 
Same mount, same upper, similar optic. The Razor 1-6 has 4" consistent eye relief, and I keep it quite far back on the receiver.

This can be influenced by your shooting stance too though. If you're square to target in a modern shooting stance, your face should sit further back. But if you're diagonal to target, using an old school Olympic stance, or primarily shooting prone, you could find your face further forward on the stock, and hence mount the optic further out.

24982586776_5bccbc132e_b.jpg
 
Move the scope back as far as needed to get correct eye relief in a comfortable shooting position. If you have to ditch the iron sights to get it in the right spot do it since you will probably never use them since you bought a quality optic that you can be 99% sure won't fail you.

Extend/collapse your stock to your proper length. Set the scope to 4x since that's where your shortest eye relief will be for that optic and snug it down on the rail just so that it doesn't fall off, you'll be moving it around a few times.

Close your eyes, shoulder the rifle with a good cheek rest. Open you eyes and look down the scope. Is the sight image clear with even dark ring around the sight picture? No? Move the optic further away or closer as needed. Close your eyes and repeat. You will probably end up with the optic sitting right over your charging handle.

Listen to these guys. An optic has to function, no point having a 4x scope if it only functions well on 1x
 
Extend/collapse your stock to your proper length. Set the scope to 4x since that's where your shortest eye relief will be for that optic and snug it down on the rail just so that it doesn't fall off, you'll be moving it around a few times.

Close your eyes, shoulder the rifle with a good cheek rest. Open you eyes and look down the scope. Is the sight image clear with even dark ring around the sight picture? No? Move the optic further away or closer as needed. Close your eyes and repeat. You will probably end up with the optic sitting right over your charging handle.
Every now and then you find a post that's like a perfect little nugget of knowledge--this is one of those. Well done!
 
Oh snap, now you done it. You said the user probably won't ever need their BUIS. You're in for it now. The interweb commandos are gonna come after your ass for speaking that truth.

Ya, the internet commandos that think co-witness is useful can go practice their ninja rolls in their moms basement. The only thing co-witness is good for is zeroing your Bushnell dot sight when you get it back from warranty replacement. To me all co-witness does is congest the sight picture and is completely unnecessary if you spend the money on a quality sight and carry a spare battery (if it uses them) you should never need to use your BUIS.
When it comes to actually shooting, buy a quality optic and forget about the rest. The op paid good money for a quality 1-4 Trijicon, no batteries to die and they're built pretty darn tough so if he breaks it he probably has other problems.
Not many people on here actually use their AR for anything other than plinking and the few that compete know enough to spend the money on quality gear and carry a spare battery so having another set of sights seems pointless to me when all it does is add weight and clutter up the rifle. No lives are on the line, no terrorists are going to take over and no zombies are going to get you when your battery goes dead at an inopportune time and you don't have a set of BUIS ready to deploy.
I have back up irons on a couple of my rifles but I would never sacrifice correct placement of my optic to have them. I use quick detach mounts so I can swap to irons if I feel like it as I sometimes like to shoot with irons. Those days though I'll usually just pull out my AR-180B-2.

What Trinmon wrote is exactly the right way to set your optic in the correct spot. If you can still fit your BUIS after doing that then fill your boots but I would never put my optic in a bad spot just to keep a set of BUIS on my rifle.
 
Ya, the internet commandos that think co-witness is useful can go practice their ninja rolls in their moms basement. The only thing co-witness is good for is zeroing your Bushnell dot sight when you get it back from warranty replacement. To me all co-witness does is congest the sight picture and is completely unnecessary if you spend the money on a quality sight and carry a spare battery (if it uses them) you should never need to use your BUIS.
When it comes to actually shooting, buy a quality optic and forget about the rest. The op paid good money for a quality 1-4 Trijicon, no batteries to die and they're built pretty darn tough so if he breaks it he probably has other problems.

Not many people on here actually use their AR for anything other than plinking and the few that compete know enough to spend the money on quality gear and carry a spare battery so having another set of sights seems pointless to me when all it does is add weight and clutter up the rifle. No lives are on the line, no terrorists are going to take over and no zombies are going to get you when your battery goes dead at an inopportune time and you don't have a set of BUIS ready to deploy.
I have back up irons on a couple of my rifles but I would never sacrifice correct placement of my optic to have them. I use quick detach mounts so I can swap to irons if I feel like it as I sometimes like to shoot with irons. Those days though I'll usually just pull out my AR-180B-2.

What Trinmon wrote is exactly the right way to set your optic in the correct spot. If you can still fit your BUIS after doing that then fill your boots but I would never put my optic in a bad spot just to keep a set of BUIS on my rifle.

Very well summarized
 
You should establish the proper shooting position first, and THEN set the optics up in the position at the proper eye relief. Not the other way around !!
 
i was taught to close your eyes, get behind the gun. open your eyes once you have a natural hold on the gun. if the scope isnt perfectly clear, move it. repeat until you can do this EVERY time and get a perfect sight picture.
 
I moved it back, and I went with two clicks back on the stock. It's a little close for prone / bench with the bipod, but that only matters for my zeroing efforts. I didn't get this rifle for that though.. Once again, thanks for the good tips!

And I was able to keep the back up sights, which I'm trying to get proficient with as well.

 
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