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slingshot
01-09-2007, 8:55 AM
Regarding the carry handle and optics mounting:

First, I realized I can put it on the handle with the following benefits:
1. Scope will clear the front fixed sight
2. I can use my iron sights without removing the scope
3. Its easy to do

But with the following drawbacks:
1. Too high for a good cheek weld
2. Carry handle mount doesn't maintain zero well

On the other hand, I can remove the carry handle and put it on the rail but the fixed front sight will partially obscure the scope's field of view. I don't need BUIS, but I really don't want to chop off the front sight. I'd like to know of others experiences or suggestions who have mounted a scope on a rifle with a fixed front sight. Is the blur nothing to worry about? Is it sufficient to mount it up on "super high" scope rings? Do I need one of those expensive LaRue tactical SPR mounts? Or, must I bite the bullet and take off the front and replace it with a flip up?

:D

rocknut
01-09-2007, 9:05 AM
I haven't mounted mine yet to let you know about the front sight in the scope, but here is a high one piece scope mount from model 1 sales that should serve well and not break the bank.
http://www.model1sales.com/item-detail.cfm?ID=SMR001&storeid=1&image=mountring.gif&CFID=15605366&CFTOKEN=83720501

maxicon
01-09-2007, 9:35 AM
The front site won't be an issue with a magnified scope. It will just be a blur, and you'll tune it out. A carry handle mount is probably the worst solution for a flattop upper, IME.

My big problem with scopes on the AR is the eye relief/cheek weld tradeoff - the standard flattop rail won't mount the scope far enough forward for me. I have one of the Armalite offset one-piece mounts, and that helps, but then the cheek weld starts to be a problem, and you have limited adjustments.

My best solution so far has been to use an extended rail. I have several, and each has their pros and cons, but they let you mount the scope further forward, and control scope height with the rings. Extended rails provide the most flexibility, since you can change rings and ring positions, add riser blocks, etc.

A couple of sources for good quality inexpensive rails are YHM (http://www.yankeehillmachine.com/store/rails.html) and RRA's scout rail (http://www.rockriverarms.com/item-detail.cfm?ID=AR0134&storeid=1&image=mnts3.gif). For experimenting on a budget, it's hard to beat YHM's gear.

It's worth remembering that each gizmo you add on between your receiver and scope adds a bit more slop and more points to loosen, which is a benefit of simple systems like the Armalite offset mount.

slingshot
01-09-2007, 9:57 AM
The front site won't be an issue with a magnified scope. It will just be a blur, and you'll tune it out. A carry handle mount is probably the worst solution for a flattop upper, IME.

Thanks for the info, thats great to know.

If you had an unlimited budget, what configuration would you get? The LaRue SPR mount ($200) and a quality non-extended rail riser? Seems like this would be the most stable and vibration resistant.

Forever-A-Soldier
01-09-2007, 10:01 AM
Just sold this AR setup, but I use the same mount with a Bushnell 3x9 MilDot on my other AR. The one in the pic is a 50mm objective lense, so your Nixon should work with the mount I use which is the Rock River Arms High Riser w/Rings mount. Also, the Matech BUIS, fits perfectly with it on the flat top receivers.

http://www.hunt101.com/img/460578.jpg

F.A.S. Out

rocknut
01-09-2007, 10:29 AM
Ten Percent Firearms sells the RRA one piece scope mount for $45. That sounds like an even better deal. He is out of stock right now though. I'm an RRA fan so that will probably be my choice now instead of the m1s one. (m1s sells RRA parts though so theirs could be RRA. 10% is cheaper though.)

donger
01-09-2007, 11:00 AM
Save yourself time and frustration by biting the bullet and getting the LaRue SPR.

maxicon
01-09-2007, 11:05 AM
If you had an unlimited budget, what configuration would you get? The LaRue SPR mount ($200) and a quality non-extended rail riser? Seems like this would be the most stable and vibration resistant.

Tough call. It really depends on what you're going to do with it.

I'm a value guy, and like good quality, less expensive stuff (usually used), so I never really looked into LaRue and such in detail. Great gear, but too expensive for me.

I also like to swap optics across a lot of platforms (some without Picatinny rails), and will switch between standard scopes, scout scopes, red dots, Eotech, etc, so a dedicated scope mount like the SPR isn't as flexible as I'd like. I don't really use my Armalite mount much. The repeatable quick-release on the LaRue is a great thing, though, and I like to transport scopes unmounted to help avoid whacking them.

So, if I wanted to mount a standard scope on a flattop AR and leave it dedicated, I could see using one of those mounts, and the LaRue would be a good bet for that. I'd try it or the Armalite without a riser first, as it should work pretty well with your Nikon - that's pretty much what that style mount is designed for.

Here's an interesting discussion comparing the Armalite mount to the LaRue:
http://www.ar15.com/forums/topic.html?b=3&f=18&t=308386

tenpercentfirearms
01-11-2007, 9:20 AM
I got my high riser mounts back in and I also have the elevated rail too.

Your other options is to get a Stag Arms gas block. As long as you have a good wrench, a hammer, and some punches, you should be able to get the old front sight base off and put on a railed block.

http://www.tenpercentfirearms.com/index.php?main_page=product_info&cPath=17&products_id=119

tenpercentfirearms
01-11-2007, 10:01 AM
I have never tried it. Some guys suggest at a higher magnification that the front sight doesn't get in the way. I personally have not tried it to find out.

Fjold
01-11-2007, 10:05 AM
Your other options is to get a Stag Arms gas block. As long as you have a good wrench, a hammer, and some punches, you should be able to get the old front sight base off and put on a railed block.

http://www.tenpercentfirearms.com/index.php?main_page=product_info&cPath=17&products_id=119

Wes, you need to change the description on your webpage for the Stag gas block, it says:

"Stag Arms gas block with picatinny rail. Replaces the standard front sight tower by punching out the two pins. The gas block then attaches with two allen screws."

You actually have to remove three (3) pins because there is a roll pin holding the gas tube.

tenpercentfirearms
01-11-2007, 11:01 AM
Thanks, I fixed it.

maxicon
01-14-2007, 11:06 AM
Here's some pics of my Armalite 1 piece mount on a JT bull varmint upper, with a Mueller 4-16x50 AO Sportsdot in it, all on a Fab 10 lower with A2 stock.

The mount's very sturdy and stable, if a bit heavy at 7.5 oz. The Mueller's also heavy at 23.4 oz, but it's a heavy gun, at 11 lb 14 oz with scope and bipod.

The main problem is that the eye relief is still a little far back for me, and the scope's as far forward in the rings as it will go. Eye relief is perfect if I move the mount one notch further forward, but then the mount contacts the handguard at the front and lifts it just a bit (you can see how close it is in the pics).

I'll probably take a little bit off the front of the mount and leave it permanently attached on this gun. There's also no room for BUIS, but you don't really need that on a varminter.

http://www.maxicon.com/guns/ar/Fab10-Varmint-Mueller-1.jpg

http://www.maxicon.com/guns/ar/Fab10-Varmint-Mueller-2.jpg

slingshot
01-14-2007, 12:32 PM
Here's some pics of my Armalite 1 piece mount on a JT bull varmint upper, with a Mueller 4-16x50 AO Sportsdot in it, all on a Fab 10 lower with A2 stock.

The mount's very sturdy and stable, if a bit heavy at 7.5 oz. The Mueller's also heavy at 23.4 oz, but it's a heavy gun, at 11 lb 14 oz with scope and bipod.

The main problem is that the eye relief is still a little far back for me, and the scope's as far forward in the rings as it will go. Eye relief is perfect if I move the mount one notch further forward, but then the mount contacts the handguard at the front and lifts it just a bit (you can see how close it is in the pics).

I'll probably take a little bit off the front of the mount and leave it permanently attached on this gun. There's also no room for BUIS, but you don't really need that on a varminter.


Maybe since I'm going with rings I will have better luck. If you could just move that rear ring forward a bit on your one-piece mount, your problem would be solved. Also, since my rings plus riser are higher than your mount, my neck will naturally sit a little higher and farther back. I'll report back on the results with some detailed measurements in a couple months.

Scarecrow Repair
01-14-2007, 1:56 PM
Maybe since I'm going with rings I will have better luck. If you could just move that rear ring forward a bit on your one-piece mount, your problem would be solved.
His one piece mount has the forward ring ahead of the rail. If he went to individual rings, the scope turret could not move any further forward than now.

What he needs to do is cut the one piece into three pieces and toss the middle piece :-)

bwiese
01-14-2007, 2:52 PM
I have several ARs with ACOG and Elcan sights (3x, 3.4x or 4X magnifications).

The front iron sight area is just a blur at the bottom of the scope image. You will become accustomed to it. I have no idea how this would appear at 2X, perhaps a tad more visible...

An unmagnified 1X sight can be set up to 'co-witness' w/irons, so the view of the front sight post is in fact necessary & useful.

BTW, the term "A3" for flattop is a misnomer, someone just incremented a digit from M16A2. Flattops are really termed "A4", derived from M16A4.

C.G.
01-14-2007, 3:26 PM
I have several ARs with ACOG and Elcan sights (3x, 3.4x or 4X magnifications).

The front iron sight area is just a blur at the bottom of the scope image. You will become accustomed to it. I have no idea how this would appear at 2X, perhaps a tad more visible...

An unmagnified 1X sight can be set up to 'co-witness' w/irons, so the view of the front sight post is in fact necessary & useful.

BTW, the term "A3" for flattop is a misnomer, someone just incremented a digit from M16A2. Flattops are really termed "A4", derived from M16A4.

Bill, which of the two (Elcan vs Acog) do you prefer? I will purchase one of them soon and at this point I am leaning toward the Acog, but wouldn't hurt to have more input.

slingshot
01-14-2007, 5:43 PM
His one piece mount has the forward ring ahead of the rail. If he went to individual rings, the scope turret could not move any further forward than now.

What he needs to do is cut the one piece into three pieces and toss the middle piece :-)

What I meant is that I'm going with an extended rail/riser + rings which would let you move the scope forward a bit at the cost of sacrificing stability from the distance between rings.

Also, is there a standard for the minimum length of the 1"/30mm tube section of a scope? If his Armalite mount was any longer, it wouldn't fit his scope. But you also bring up a good point: he doesn't actually gain anything with the Armalite mount. He if had gone with just rings, he could put it just as far forward.

maxicon
01-14-2007, 5:50 PM
His one piece mount has the forward ring ahead of the rail. If he went to individual rings, the scope turret could not move any further forward than now.

What he needs to do is cut the one piece into three pieces and toss the middle piece :-)

Yah, I tried this one in a couple of configs, including a riser and various height rings, and the Armalite mount is better than individual rings for the reason you mentioned. A scout rail helped that by letting me move the rings further forward, but added another layer of connections.

I like the rigidity and sturdiness of the one-piece, and because the alignment is built in to the mount, it's good at not marking the scopes.

At this point, I'm going to file a bit off for handguard clearance, paint the whole thing black, move it forward a notch, and call it good.

Scarecrow Repair
01-14-2007, 8:33 PM
What I meant is that I'm going with an extended rail/riser + rings which would let you move the scope forward a bit at the cost of sacrificing stability from the distance between rings.

And what I meant is that I don't think that scope could move any further forward if it were on rings; the scope turret wil run into the back of the front ring. There's clearance as he has it because the front ring is anged forward. He can't move his single piece mount forward because it hits the handguard, which you would avoid, but then the scope would be at its limit w/ respect to the forward ring.

Or maybe you have a riser which basically puts a new rail mount above and forward of the builtin rails? I don't know enough about this stuff yet, and if so, I apologize :-)

five.five-six
01-14-2007, 10:23 PM
Here's some pics of my Armalite 1 piece mount on a JT bull varmint upper, with a Mueller 4-16x50 AO Sportsdot in it, all on a Fab 10 lower with A2 stock.

The mount's very sturdy and stable, if a bit heavy at 7.5 oz. The Mueller's also heavy at 23.4 oz, but it's a heavy gun, at 11 lb 14 oz with scope and bipod.

The main problem is that the eye relief is still a little far back for me, and the scope's as far forward in the rings as it will go. Eye relief is perfect if I move the mount one notch further forward, but then the mount contacts the handguard at the front and lifts it just a bit (you can see how close it is in the pics).

I'll probably take a little bit off the front of the mount and leave it permanently attached on this gun. There's also no room for BUIS, but you don't really need that on a varminter.


http://www.maxicon.com/guns/ar/Fab10-Varmint-Mueller-2.jpg


This may be why everyone on afr.com loves the super sniper so much, the scope is designed such that even with the thick Armalite mounts, I get the eyepiece about flush with the rear of the receiver


nice rifle :)

bwiese
01-14-2007, 11:21 PM
Bill, which of the two (Elcan vs Acog) do you prefer? I will purchase one of them soon and at this point I am leaning toward the Acog, but wouldn't hurt to have more input.

I do like the slightly more forgiving/flexible eye relief (but not by much) on the Elcan. However this may be a reflection of the difference in magnification (3.4X on Elcan vs 4X on my main ACOGs). I don't have that much time behind my 3X ACOG to really have a great opinion about eye relief yet.

Glass is about equal on Elcan vs ACOG. Elcan does not have a full merged crosshair (the reticle has gaps) vs a fairly clean 'arrow tip' on the ACOG.
Elcan is a bit bulkier.

Supposedly the ACOGs are actually a tad more rugged than the Elcans. Probably not significant to we range types, and they're certainly good enouhg for travel. I've flown with Elcans & ACOGs on my ARs and they keep their zeros...

Now, one other note: I am speaking of the traditional Elcan sight. There is a newer M143 sight tuned for M4 and maybe MG use, and there's a brand new Elcan scope ($1400) that has *switchable* 1X (dot sight) & 4X magnified sight.

Xenophobe has this latter Elcan sight on his S&W rifle and I think he likes it :)

C.G.
01-15-2007, 12:03 AM
I do like the slightly more forgiving/flexible eye relief (but not by much) on the Elcan. However this may be a reflection of the difference in magnification (3.4X on Elcan vs 4X on my main ACOGs). I don't have that much time behind my 3X ACOG to really have a great opinion about eye relief yet.

Glass is about equal on Elcan vs ACOG. Elcan does not have a full merged crosshair (the reticle has gaps) vs a fairly clean 'arrow tip' on the ACOG.
Elcan is a bit bulkier.

Supposedly the ACOGs are actually a tad more rugged than the Elcans. Probably not significant to we range types, and they're certainly good enouhg for travel. I've flown with Elcans & ACOGs on my ARs and they keep their zeros...

Now, one other note: I am speaking of the traditional Elcan sight. There is a newer M143 sight tuned for M4 and maybe MG use, and there's a brand new Elcan scope ($1400) that has *switchable* 1X (dot sight) & 4X magnified sight.

Xenophobe has this latter Elcan sight on his S&W rifle and I think he likes it :)

Thanks for the input, very informative.:)

tenpercentfirearms
01-15-2007, 9:24 AM
On my one piece mount, I actually mount it so far forward the front of the mount is actually off of the upper rail. I just tighten it down anyway and I have not had a loss of zero problem yet.

proraptor
01-15-2007, 9:37 AM
This is exactly why I went with a monolythic rail system....I can mount anythin I want anywhere with the continuous top rail

slingshot
01-15-2007, 10:22 AM
This is exactly why I went with a monolythic rail system....I can mount anythin I want anywhere with the continuous top rail

I'm not sure what you mean by a monolithic rail system. Are you referring to a one-piece mount like the Armalite or an extended rail like a scout rail?

proraptor
01-15-2007, 10:25 AM
My free floating rail is from midwest industries and it 12 inches long. Its called monolythic because the rail butts right against the upper receiver and makes the top rail on the gun one long top rail. There is no gap between the rails and the upper receiver so you have a ton of options when it comes to mounting stuff anywhere on top

slingshot
01-15-2007, 10:28 AM
My free floating rail is from midwest industries and it 12 inches long. Its called monolythic because the rail butts right against the upper receiver and makes the top rail on the gun one long top rail. There is no gap between the rails and the upper receiver so you have a ton of options when it comes to mounting stuff anywhere on top

Thats a nice solution. Gives you a rail all the way down the barrel I see. Comes at a price though:

http://www.midwestindustriesinc.com/ar_free_float_forearms.htm

mike452
01-15-2007, 10:47 AM
Regarding the carry handle and optics mounting:

First, I realized I can put it on the handle with the following benefits:
1. Scope will clear the front fixed sight
2. I can use my iron sights without removing the scope
3. Its easy to do

But with the following drawbacks:
1. Too high for a good cheek weld
2. Carry handle mount doesn't maintain zero well



I never had much success mounting a scope securely on the carry handle. Maybe it's because I didn't want to drive the nut into the aluminum handle too deep. It does look ridiculous shooting with your chin on the stock. :D

The front sight tower doesn’t block the crosshair on the scope on my flattop, but I do see it. I never noticed it at 16x zoom. I have a SS 16x in Leupold med rings on a GG&G raiser.
I would go with a rail raiser so your rings can be used on non-AR rifles when you change scopes.

I found the front sight useless after I mounted a riflescope on the flattop. I have never taken it off to use my BUIS after I zeroed in the scope. I've only done that on my M4 with an Eotech.

proraptor
01-15-2007, 11:08 AM
Thats a nice solution. Gives you a rail all the way down the barrel I see. Comes at a price though:

http://www.midwestindustriesinc.com/ar_free_float_forearms.htm

It does cost but it gives you a bunch of different options if you need to mount anything not to mention looks awesome! LOL

maxicon
01-15-2007, 10:44 PM
On my one piece mount, I actually mount it so far forward the front of the mount is actually off of the upper rail. I just tighten it down anyway and I have not had a loss of zero problem yet.

I took a closer look, and that's a good option. I'm going to set mine up that way and give it a try.

As long as the recoil lug is in a slot, the stability should be good. On the Armalite, the crosspieces for the mounting screws aren't designed to locate the mount or provide recoil stability; they're just screw shanks that fit down into the slots.

That gives me a couple more slots of forward position - I like it!

maxicon
01-15-2007, 10:51 PM
I never had much success mounting a scope securely on the carry handle. Maybe it's because I didn't want to drive the nut into the aluminum handle too deep. It does look ridiculous shooting with your chin on the stock. :D

I mounted a scope on the carry handle of my .22 upper because it's the best way for me to get groups, but it's definitely too high to shoot comfortably, and would be worse with centerfire.

The ARMS #02 mount held pretty securely for the few hundred rounds I fired (just .22, after all), but people get their best results bedding this type of mount to the handle, as someone posted earlier.

Here's a pic of my Leupold VX1 4-12x40 mounted up there. It wasn't bad shooting off the bench, but would have been a pain freestanding.

http://www.maxicon.com/guns/ar/DPMS_22-Leup12-1a.jpg

grywlfbg
01-16-2007, 12:26 PM
I got my high riser mounts back in and I also have the elevated rail too.

Your other options is to get a Stag Arms gas block. As long as you have a good wrench, a hammer, and some punches, you should be able to get the old front sight base off and put on a railed block.

http://www.tenpercentfirearms.com/index.php?main_page=product_info&cPath=17&products_id=119

Wes,

I'm thinking about going w/ an optic-only rifle for tac rifle competition and I'm hoping the EOTech 4x magnifier is available soon. I'm planning to remove my rear sight to make rom for the magnifier so I figure I should just remove the front sight as well.

So my question is, do I just need that Stag gas block and the new roll pins or is there something else I'll need?

Should have just ordered my upper this way from you but I wasn't sure what I was going to do yet.

Chris

slingshot
01-16-2007, 2:53 PM
I have a similar question. What is the function of the gas block? Does it hold in the gas tube? Does the standard A2 front sight perform this function?

mike452
01-16-2007, 3:03 PM
I have a similar question. What is the function of the gas block? Does it hold in the gas tube? Does the standard A2 front sight perform this function?

yes and yes

maxicon
01-18-2007, 9:29 AM
I took a closer look, and that's a good option. I'm going to set mine up that way and give it a try.

As long as the recoil lug is in a slot, the stability should be good. On the Armalite, the crosspieces for the mounting screws aren't designed to locate the mount or provide recoil stability; they're just screw shanks that fit down into the slots.

OK, I know everyone's getting tired of hearing about this, but here's the final config on this one (for now, anyway). Thanks to 10% for the suggestion!

I remounted the Armalite mount with the recoil lug in the last slot, and it's just about right for me. It leaves the front cross-slot screw hanging in front of the receiver, but that shouldn't be an issue. If you like your nose against the charging handle, it's still not enough eye relief with this Mueller scope (haven't tried a Leupold yet).

This mounts the bottom of the scope tube about 0.75" above the top of the flattop rail, giving a scope axis center about 1.25" above the rail. It turns out I didn't need to relieve the mount for handguard clearance - I was using too stiff a shim for checking clearance.

http://www.maxicon.com/guns/ar/Fab10-Varmint-Mueller-3a.jpg

Here's a pic of the mount with the recoil lug and the cross-slot screws. The lug should take all the recoil stress on this mount, and the cross-slot screws just hold the thing on. They shouldn't be taking any recoil stress at all.

http://www.maxicon.com/guns/ar/arm_single_pc_lug-a.jpg

I did get a little help during the photo session from one of the cats:

http://www.maxicon.com/guns/ar/Fab10-Varmint-Lily-1a.jpg