AR scope mount... am I doing it right?

[v35]

I know little about rifles and almost nothing about scopes. That's a Nikon Prostaff Rimfire II 4-12x40 and an M&P15-22.

Does everything appear to be mounted correctly?

From what I read here I had been partial to Leupold scopes, but Cabela's talked me out of Leupold and into the Nikon. I still chose the one piece Leupold mount due to the company's reputation and the mount's apparent quality. $90, but one piece seems simpler to me than two separate rings. Besides, I may use it on another AR when I get a scope for it.

 

[GarySTL]

Just from the photo it looks OK to me. Is it solidly mounted? No movement or wiggle? Mount properly set down in the rails? Screws nice and tight? Is the eye relief correct?

 

[v35]

Yes to all but I don't know what I should be doing with eye relief. The stock is fully extended, and I can see the target OK in that position, but I'm not sure exactly where my cheek should rest. Maybe I just need to move the scope forward or back until it feels right...?

Oh and one more thing. With handguns the proper sight picture is "front sight in focus, target blurry". That's what I've been doing for years and I'm quite pleased with my handgun skills. Does the same principle apply to scopes? In other words, the reticle is sharp. Should the target be just as sharp? Because it's a little fuzzy with the scope at maximum magnification (12x).

 

[rcmodel]

X-hair and target should both be sharp as a tack.

But the target won't be at 12x at closer range.

It should be clear and sharp beyond 30-40 yards though.

The rear eyepiece is for focusing the scope to your eyesight.

Point the scope at the bright sky and adjust the rear lens by glancing through it until the X-hairs are clear and sharp.

Do not try to adjust it while staring through it!!

Your eye will try to adjust for out of focus faster then you can screw the rear lens in & out.

rc

 

[GarySTL]

That scope probably has no parallax adjustment, so do as rcmodel says.

 

[rcmodel]

Even if the scope does have AO, you still need to set it on infinity, and adjust the rear lens to your eyesight while setting it up the first time.

rc

 

[v35]

But the target won't be at 12x at closer range.

It should be clear and sharp beyond 30-40 yards though.

Got it.

Targets farther away are clear.

This is definitely a lot of fun.

 

[rcmodel]

As to the eye relief question??

I like to set the scope far enough forward I have a clear view while shooting from the prone position. (Laying flat on the ground.)

That gets your head about as close to the scope as it will ever get from any other awkward field shooting positions.

It may be a minor stretch when standing.

But it beats getting hit in the eye with the scope when you are leaning over a tree limb or stump.

rc

 

[greyling22]

put the scope on 10x or so, set it loosely on the gun so you can move it forwards or backwards. Close your eyes, shoulder the rifle (or get down behind it if you are on sandbags) and settle into a comfortable position. Now open your eye. Is the scope too far forward or back? adjust it and try again. When you get that right, check and see if that position works well for 4x. Generally your eye needs to be closer to the scope on 12x than 4x.

That said, you may have the wrong scope for that rifle. It is really too much magnification and the parallax is set wrong for shorter range .22lr stuff. I know that it's a rimfire scope and the parallax is set shorter than for rifles, but a 75yd parallax is really going to leave everything up close kind of blurry. Especially at higher magnifications.

 

[pjeski]

Before you tighten it down on the rail, be sure it is pushed forward so that it is against the front side of the slot(s).

 

[Walkalong]

Looks a little far back to me, but it all depends on the eye relief and your preference for head position.

Before you tighten it down on the rail, be sure it is pushed forward so that it is against the front side of the slot(s).

Yep.

 

[v35]

Before you tighten it down on the rail, be sure it is pushed forward so that it is against the front side of the slot(s).

Good idea, thanks!

After some trial and error adjustments (below... I don't have a bench rest) I'm liking the results. Right now I'm getting accustomed to technique. The rounds I'm using are CCI "Tactical AR" I have plenty of .22lr on hand but most of it is the cheap bulk stuff. Do you think "match grade" .22lr will make any difference in the M&P15-22?

Chances are I'll be buying another .22lr rifle before I buy another scope. The M&P is a lot of fun, but I never intended it to be anything more than a fun thing to play with and to learn about longer range shooting than the handguns I'm familiar with.

 

[rcmodel]

Every .22 is a rule unto itself as to what ammo it shoots best.

Match ammo might tighten your groups, or not.

Best thing to do is try a box of everything you can find and try them all.

Then, if you find one that is noticeably better then the others?

go back and get all you can of the same lot number.

rc

 

[CapnMac]

Way way back in the 80s, a bud and I both scored on a deal on Nylon 55's. Bought them about two days' apart, serial numbers only avout 100 apart.
To this day, mine "like" Winchester white box solids the best, followed by PMC HPs. His only behaved with Eley TenX--dang thing would only shoot to about minute of 2l coke bottle with PMC ammo. Go figure. Your mileage may vary. Professional driver on closed course.

As to that scope, the way I was trained to shoulder an AR, that scope is about 3" too far back (presuming it has about a 3" eye relief).
But, that's me, nose to charging handle.

 

[v35]

Thanks all; I'll move the scope just forward of the charging handle. The way it is it's hard to grab anyway.

This scope has a 3.7" eye relief.

 

[pjeski]

Once you get your cheek weld figured out, you might be surprised how close your nose is to the charging handle. (Maybe)

 

[RainDodger]

... and if you DO like Leupold scopes, don't let the counter-jockey at Cabela's talk you out of one.

 

[strambo]

I'd move the mount as far forward as you can while keeping it on the upper. Then, adjust the scope tube back in the rings if needed. As a rough guide, the rear ocular should be in a similar position to where a rear sight would be. Fine tune in accordance with the advice given by other posters.

 

[henschman]

It is bad form to "turtle neck" on a rifle, by scrunching your head back on the stock. The best practice is to "turkey neck" -- stretch your head as far forward as it will go. This leaves no slack in your neck, so your head doesn't move under recoil. While that probably isn't going to happen on a .22, it is a good habit to get in for shooting center fire, and it makes for a very consistent head position.

As a practical matter on an AR, you can't really get your head any further than where your nose touches the charging handle... otherwise you end up face to charging handle. If you have a collapsible stock, you should set it to the length that puts you nose to charging handle when you're fully turkey necked out in the prone position. For most people this will be fully extended or close to it. From there you mount the scope so you get proper eye relief in the prone position.

If you want to learn some solid rifle ,arksmanship fundamentals, I recommend taking that rifle to an Appleseed marksmanship clinic. They are nationwide, so you should be able to find one near you.

 

[v35]

I re-mounted the scope so that the Leupold mount is now as far forward on the lower as possible. Results are much better: the target is clear at 50 yards, and no problem at all hitting the 10 ring even while standing. I could mount it even more forward if needed.

As it turns out my nose does really come pretty close to the charging handle, and yes I do feel as though I'm stretching my neck out.

I no longer have trouble acquiring the target either, whereas in the previous position it would easily "black out" if my eye wasn't in just the right place.

Everything seems to have come together nicely

For some background on the subject: newbie range report