Rifle Scopes Extended 34mm scope mount for an ar15

GreenMushroom

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I'm moving my g3 from a mono to a standard upper and want the scope further forward than my scalarworks 07 will allow. I'm looking to move it .5" or more forward. I have an extended bobro mount and I'm happy with it but it's kind of a tank and this is a lightish weight build. The adm recon x is an option but it's pretty heavy and the rings look fat on top so I'm not sure my piggyback would work.

I don't care if it's quick connect but solid return to zero would be nice. Any options I'm missing? Nightforce service rifle unimount would be perfect but they don't seem to make it in 34mm.

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Neurotic

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I don't know if this extends far enough for you, but I like the Sig Alpha3s. My 34mm versions are 4.9-5 ounces and fit nicely.

https://www.sigsauer.com/alpha3-scope-mounts.html

The Vortex mount above has a ton of iver-hang, but they're portly at 8.9-9 ounces. My last one had a top cap that slightly pinched the tube. It was nothing greatly damaging, but I couldn't rotate the scope with the cap in place.

Edit: the weights are my measurements. Sig doesn't seem to provide weights and Vortex lists vastly different weights for the 0 and 20 moa models, but they weight the same.
 

longshot2000

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    The answer will depend upon the scope and the overall quality of the scope and rifle combo. The two that come to mind the fastest are Geissele extended AR mount and LaRue LT204. Of the two, Geissele is better, but a little costlier. Also good are Nightforce Unimount, ARC M-Brace. From there, there are dozens. Bobro and American Defense Manufacturing (Recon is a good mount)
     

    srt-4_uk

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    If the Scalarworks mount isn't far enough forward then the ARC M-brace, Larue 204, and Nightforce won't be either.
     

    GreenMushroom

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    The vortex above is the offset I'm looking for but I was hoping for something lighter but there doesn't seem to be a lot of options. Will probably just go with another bobro. This is the rifle with a g2 that's being replaced by the g3 and I'm looking for similar eye relief but probably just a touch more. The g3 sticks further out the back so I'll need the extended vrs the standard that the g2 is mounted in.

    20220415_071009.jpg
     

    sjmpcc022

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    Arken has a 34mm cantilever 20moa mount for 65$. I bought one with the SH4 4-16X50 scope when they were 30% off.

    If you want to spend more for a top of the line mount F3R Machine has an AR mount, not positive on 34mm, check their website. I have the 34mm 20 moa one piece mount on my PRS rifle and I would put that mount up against any, including Spuhr. Fire away haters, but please at least watch the video on F3R's website before you torch me!;)
     

    GreenMushroom

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    GreenMushroom

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    Haven’t seen JP mentioned yet.

    Those look nice but I don't think it would get it much further forward than the Scalarworks. I need one where the forward most lug is roughly in line the the rear ring. So far I have the vortex above and.....

    Adm recon x at 8.4 with titanium levers
    download.jpeg-4.jpg


    Bobro extended at 10oz
    img_0571 (2).jpg


    The nightforce service rifle unimount would be perfect but they don't seem to make one in 34mm unless I'm missing something. Unimount is 5.6 oz and I'd think the service rifle is a bit more but probably still pretty light.

    download.jpeg-5.jpg


    Eta the larue spr-e looks interesting. They don't list the weight but a little research yielded 7.7oz. I'd assume that's the version with the throw levers so I wonder how much weight you save with the bolt on version. I've never even handled a larue mount but they seem to have a solid reputation though I know there's some hate out there.

    a39a1bf322d63cf4ad7a8adb3cbbe2f9.jpg
     
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    Brym427

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    I use this for my 1-8 atacr on my 11.5 sr15. 8.7oz. But the weight difference between mounts is going to be minimal. If youre worried about a ounce or two just go to the gym
     
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    GreenMushroom

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    That looks really nice. I can't find a decent picture of the underside. Seems like everything is even with or back of the rear ring. Don't own any Spuhr stuff so maybe it's rime to try one out.

    Looks like they have a DPP plate as well that might get the dot a little lower. The 30mm reptilia mount is perfection but the 34mm is a little tall imo.
     
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    KineticPerformance

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    The vortex above is the offset I'm looking for but I was hoping for something lighter but there doesn't seem to be a lot of options. Will probably just go with another bobro. This is the rifle with a g2 that's being replaced by the g3 and I'm looking for similar eye relief but probably just a touch more. The g3 sticks further out the back so I'll need the extended vrs the standard that the g2 is mounted in.

    View attachment 7901352
    I would say there is almost no way you need a mount that will place the scope that far forward unless you are shooting SR with a nose to charging handle weld, are over 6'4, or are shooting with your stock collapsed (in which case you should lengthen it unless you are half the height of a regular person). I shoot SR with the Geissele mount and it's great for very deliberate shooting but it's lower than I want for any kind of action shooting; my work and match rifle mounts vary from 1.54" to 2.26" and the Geissele SR mount is 1.3" tall. If you really need your scope that far forward you are probably going to be a SR riser and conventional rings.
     

    bill_van

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    I shoot nose to the charging handle and find the ADM Recon X works well. It has a 3" offset and probably the most extended mount on the market. The vertical split rings have not been an issue, if you've never used one, ALWAYS torque the 2 bottom screws first then move to top using shims to ensure the gap is even and equal. Sometimes the particular scope's eye relief will lat you set the mount back a slot or two. In my case, the bottom of the mount is even with the end of the receiver.

    Here's a link:
     
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    Brym427

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    That looks really nice. I can't find a decent picture of the underside. Seems like everything is even with or back of the rear ring. Don't own any Spuhr stuff so maybe it's rime to try one out.

    Looks like they have a DPP plate as well that might get the dot a little lower. The 30mm reptilia mount is perfection but the 34mm is a little tall imo.

    What parts of the spuhr mount do you want a pic of? Ill take some
     
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    GreenMushroom

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    Just the bottom. Just wanted to make sure there weren't recoil lugs further forward past the rear ring. I'm assuming those two screws clamp it and have crossbolts and there's a recoil lug in there somewhere? I'm thinking the spuhr and might upgrade the dpp to an rmr at the same time. I think with the plate being a little lower than the reptilia and rmr a little shorter than the dpp it'll put the dot at just over the turret cover where I like it.
     

    GreenMushroom

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    I would say there is almost no way you need a mount that will place the scope that far forward unless you are shooting SR with a nose to charging handle weld, are over 6'4, or are shooting with your stock collapsed (in which case you should lengthen it unless you are half the height of a regular person). I shoot SR with the Geissele mount and it's great for very deliberate shooting but it's lower than I want for any kind of action shooting; my work and match rifle mounts vary from 1.54" to 2.26" and the Geissele SR mount is 1.3" tall. If you really need your scope that far forward you are probably going to be a SR riser and conventional rings.

    I have an enormous phallus and virtually no neck so ergonomically picture me as an L with legs.
     

    Brym427

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    Just the bottom. Just wanted to make sure there weren't recoil lugs further forward past the rear ring. I'm screws clamp it and have crossbolts and there's a recoil lug in there somewhere? I'm thinking the spuhr and might upgrade the dpp to an rmr at the same time. I think with the plate being a little lower than the reptilia and rmr a little shorter than the dpp it'll put the dot at just over the turret cover where I like it.
    20220629_144916.jpg

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    inertia

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    I run these scopes for 3 gun and need a lot of eye relief. I have several mounts you need to keep a close eye on how far ahead of the rear of the mount the rear ring is. None of these mounts with the rear ring close to the rear of the mount give me enough relief. The conclusion I came to is there were 2 good options for me, for competitive 3 gun, are the vortex precision above (made by seekins very good quality) or the JP extended. The JP is a bit lighter, the Vortex is very nice though and still lighter than the QD or Spuhr ideas here. Also unless you really have a QD use case stick with the fixed attachment mounts. I cant count how many times guys show up to competitions with these tactical QD setups and cant figure out why they cant hit anything, to discover something got bumped loose, broke etc.
     
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    GreenMushroom

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    I run these scopes for 3 gun and need a lot of eye relief. I have several mounts you need to keep a close eye on how far ahead of the rear of the mount the rear ring is. None of these mounts with the rear ring close to the rear of the mount give me enough relief. The conclusion I came to is there were 2 good options for me, for competitive 3 gun, are the vortex precision above (made by seekins very good quality) or the JP extended. The JP is a bit lighter, the Vortex is very nice though and still lighter than the QD or Spuhr ideas here. Also unless you really have a QD use case stick with the fixed attachment mounts. I cant count how many times guys show up to competitions with these tactical QD setups and cant figure out why they cant hit anything, to discover something got bumped loose, broke etc.

    Interesting. Recently picked up some seekins rings and they are very high quality. Any idea on the return to zero on the vortex? The g3 would be on it the vast majority of the time but I'd like to stick a thermal or an aimpoint on it occasionally. Not something I'd be switching on the fly so I don't really care about QD.
     

    inertia

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    Interesting. Recently picked up some seekins rings and they are very high quality. Any idea on the return to zero on the vortex? The g3 would be on it the vast majority of the time but I'd like to stick a thermal or an aimpoint on it occasionally. Not something I'd be switching on the fly so I don't really care about QD.
    I never remove a scope from a match rifle without rezero so not really sure but if you use a consistent torque value they never move too much. The Vortex precision is just an extended version of the 1 piece ar mount seekins sells, it's very nice and the perfect length for the razors. I expect seekins makes it on contract for vortex so it's design is litterally for that scope.
     
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    GreenMushroom

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    Unfortunate update on this. Got the vortex/seekins extended mount and was very pleased. Allowed me to get the eye relief I wanted and move the dot ahead of the elevation turret where I prefer it.

    20220904_095100.jpg


    Took it out and zeroed it and it was shooting nice groups but occasionally throwing crazy fliers. Examined things and come to find out even tightened down all the way the the mount moves easily back and fourth in the rail slot. Tried it on the bcm handguard and it clamps solidly well short of torque spec so the upper rail is out of spec. Upper is a very early Mega billet set (#17) and on close examination the rail is profiled a bit different than the handguard rail.

    So I give the mount a thumbs up but anyone buying be aware there is very little tolerance for out of spec rails. I've used bobro and adm mounts without issue. I'm about halfway between trying a bobro next or just calling the scope cursed and selling it😆. Upper has sentimental value so changing it out isn't really an option.

    Hard to see the difference in pics but it's there. Will try the mount on other uppers but I think I already have the correct answer.

    20220904_095241.jpg
     

    inertia

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    The other fixed mount that I have had good luck with that has enough eye relief for a razor is made by JP rifles. I also think geissele makes one long enough. If your upper is not properly made resorting to a qd mount to compensate you should expect performance and reliability commensurate to the compromises your making.
     

    GreenMushroom

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    Ordered up a bobro. Had a g2 1-6 on it in a bobro mount and didn't have any issues. I actually prefer quick disconnect so I can swap it out for a thermal. I've run bobro mounts for years and haven't had any issues and return to zero is always dead on but I'm aware by the nature of the design they're nowhere near as strong as the seekins mount. At any rate it's fun gun and isn't likely to take a lot of abuse.
     

    GreenMushroom

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    Wanted to add I tried the vortex/seekins mount on bcm and lmt uppers and it locked up tight well short of torque spec so it's definitely the upper.
     

    Keith E.

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    I'm moving my g3 from a mono to a standard upper and want the scope further forward than my scalarworks 07 will allow. I'm looking to move it .5" or more forward. I have an extended bobro mount and I'm happy with it but it's kind of a tank and this is a lightish weight build. The adm recon x is an option but it's pretty heavy and the rings look fat on top so I'm not sure my piggyback would work.

    I don't care if it's quick connect but solid return to zero would be nice. Any options I'm missing? Nightforce service rifle unimount would be perfect but they don't seem to make it in 34mm.

    View attachment 7900832

    IME, the Vortex mount had a ~3.5" cantilever. That happened to be too much for what I was working with.

    Keith
     
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    DrDeath

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    How good or bad or the Leupold extended mounts?? They have two types the AR brand and the IMS brand