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Largest scope for performance and symmetry on a small frame AR.

Flywheel

Dude
Supporter
Full Member
Minuteman
Nov 26, 2013
361
118
Hells Circle - Texas
Trying to get some feelers out here, maybe I can get some pictures of your setups.

I'm trying to get a general consensus of what is the considered the maximum objective size and magnification for a small frame AR versus what is symmetrical for the size and weight.

Before I get hit with the Sponge Bob meme and "UsE ThE RiGhT ToOl For the JoB", slow your roll keyboard commando. I understand, and acknowledge that. If you have ever had a piece of kit that by the specs was the "right tool for the job" , but in practice was probably the worst choice due to size and weight considerations... You understand where I am at here, I'm looking for others experiences.

My setup in question is a 20 inch 6 ARC, looking at putting a 4-20 x 50mm scope on it. I don't want it banging into everything, and don't want to have Hubble attached to the top of my rail either.

Typical engagement is going to be from 50-750. Yes... you can shoot 1k at 8-10 power, doesn't mean I don't want PID at what I may be shooting at those ranges.

Any help is appreciated, stay safe.
 
I have a 6-25x 56 on a 22” 6.5 Grendel, and a 1-6x24 on a 16” 5.56. And a couple in between too. Not really concerned about how it looks.
 
I have a 6-25x 56 on a 22” 6.5 Grendel, and a 1-6x24 on a 16” 5.56. And a couple in between too. Not really concerned about how it looks.
I hear you. Again, it's not just the look of it. Does having an optic that big mess with the balance of the rifle? Does it catch onto things because it has large exposed turrets when you're going into an urban shoot position? It's about performance not about how it looks on your Instagram. I.e. real world application of having a larger magnified optic on a smaller rifle.
 
420 and 2.5-20 on small frame ARs:

843F1B48-4149-4202-BFBB-FE9CF45DE4C6.jpeg
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I hear you. Again, it's not just the look of it. Does having an optic that big mess with the balance of the rifle? Does it catch onto things because it has large exposed turrets when you're going into an urban shoot position? It's about performance not about how it looks on your Instagram. I.e. real world application of having a larger magnified optic on a smaller rifle.
Never been an issue in PRS comps- at least not more so than any other similarly capable rifle/optic. I humped it through a run and gun once, but the 5.56 with a 1-6 or 1-8 is better for that.
 
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What kind of “urban hide” are you climbing in to that an extra 10-20mm of objective bell is going to matter??? I’m sure the book depository will be plenty big to accommodate a 50mm objective over a 42mm one.
 
What kind of “urban hide” are you climbing in to that an extra 10-20mm of objective bell is going to matter??? I’m sure the book depository will be plenty big to accommodate a 50mm objective over a 42mm one.
I'm not climbing into an "urban hide". I do regularly shoot from a concealed position within a building, from behind cars, and etc. The extra size is only an issue when you actually have to carry and use your gear. I appreciate your contribution to the discussion.
 
I really liked the NF 4-16 atacr’s I had. Low profile locking elevation. I thought they’d make the perfect gas gun optic. I used mine on my AIAT. But 16 max power vs the 20 you want. I have the 4-20 atacr as well but larger turret like the 5-25 and 7-35 and larger objective/size overall vs the 4-16

The ZCO 4-20 would be awesome….someday 🫤
 
20" 6ARC, 6-24x50 FFP, sunshade really makes it look big, but I shoot in a high sun-intensity environment, so DGAF what it looks like. and the shooting range extends out to 1,500yds. Future builds might use a 5-25x56 FFP, or similar.
Av3x6Gu.jpg


22" 6ARC, 6-24x50FFP, sunshade same thing. it gets the job done. not entering a beauty contest.
rzPyS2c.jpg
Yeah, but can you carry that thing around while shooting from buildings and from behind cars?
 
@S197

Love this setup, thought about picking it up until I found a deal on a ZCO too good to pass up.

What reticle are you running in it?
It’s just the basic tmr, and the barrel is 14.5 WOA house barrel. ZCO’s are out of my price range.
 
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Don't rule out the March FX 4.5-28x52 wide angle. March FX D28HV52WFIML I have one sitting on a large frame AR and have no regrets at all. On par with the S&B Ultra Short and ZCO 420 in both size and weight.
I have no experience with this optic, I'll have to check it out. I know March optics are good to go, just not familiar with this particular scope. I appreciate you.
 
I find my self debating aesthetics and function from time to time. I like things to look good/balanced while still functioning and serving a purpose.

Both rifles are 6.5 Grendel. 20" for stalking, and a 16" for hunting at night from a blind with a suppressor.

20 inch rifle build had a lighter weight, compact 3-9x40 Trijicon. It actually looks a little small in my opinion, but size and weight were the deciding factor.
20161102_120244.jpg


16 inch rifle has the 2.5-10x56 Trijicon. The objective looks like Hubble on there, especially with the shorter rifle. Again, this was for hunting hogs from a blind, so size and weight didn't matter. What did matter was getting every bit of usable light to my eye.
20161102_120058.jpg


Both rifles would look more balanced if I switched the optics, but not going to happen.
 
@AMG04

I appreciate you.
You're going to stay with the lower magnification on the longer gun?

Also, when shooting from your blind do you get full use of the larger objective or does it get shadow from your windows or slats?
 
The lighter scope on the longer rifle is great for walking around. Far more carrying than shooting.

The x56 is a great low light scope. I can see hogs well past sunset. If there is a full moon and clear sky I can hunt throughout the night. Never had an issue with shadows from the blind. Facing towards the setting sun is the biggest issue from time to time.
 
Don't rule out the March FX 4.5-28x52 wide angle. March FX D28HV52WFIML I have one sitting on a large frame AR and have no regrets at all. On par with the S&B Ultra Short and ZCO 420 in both size and weight.
I was between this and the ZCO and ended up choosing March. No regrets.
 

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Some of my favorites -
LRTSi 3-12 - really great., Hard to find.
Athlon 2-12 - would probably be my fave if it said "made in Japan"
Nightforce 4-16x42 - heavy but good.
SWFA 3-9 - outstanding if you can pass on illumination
 
I'm not climbing into an "urban hide". I do regularly shoot from a concealed position within a building, from behind cars, and etc. The extra size is only an issue when you actually have to carry and use your gear. I appreciate your contribution to the discussion.

He's not the only one that thinks this sounds weird. I also wonder what someone who actually carries and uses theie gear is worrying about symmetry and aesthetics for. The fact this is for a 6ARC which to my knowledge hasn't been adopted by any agencies and you're playing urban commando with is also interesting.
 
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While it is somewhat limited in the parts available, the Gunstruction app let's you mock up your builds. A lot of parts are missing, but you can at least get a good sense of what your build will look like before you start.

For example, this was my SPR build plan with a Viper PST II 3-15x44mm scope as a stand in:

VBIrJbC.jpeg


It's still a build in progress, but here it is IRL with an Athlon Ares BTR 2.5-15x50mm scope:

Y7tmHMo.jpeg
 
I have these and like them a lot:

18" 556 with ATACR 4-16x42
16" 6.8 with NX8 2.5-20x50

If I was going to build a 20" gun, I might consider something like a 4-20 or 5-20 UltraShort for the variety of it. Still, I don't think I'm missing anything with my current ones.
 
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4.5-14x50

krieger-20-inch-larue-rail-leupold-scope.jpg



45x45

molon-benchrest-001.jpg







…..
What is the rail used to mount these two scopes? I like that it lets you lower the scope to the bore line by using regular rings. Thanks in advance. I couldn't see markings on either one. Nice rigs.
 
79A7989A-1887-4A61-8D06-2A7BEBD0C0E7.jpeg

Top firearm, Vortex Viper PST 3-15x44 SFP on a small frame .224V build. I like this for size. This has a Bartlien Barrel in an Aero set, Larue MBT-2S trigger.

Bottom firearm, Nightforce SHV 5-20x56 SFP on a large frame 6.5CM build. Swapping this to my .22 trainer for a Vortex Viper PST Gen 2 5-25x56. This has a Proof CF barrel in a Grey Ghost Precision set, Geissele National Match High Speed Trigger.

A32F01F7-4D27-47E1-8DE5-9773BCF2A609.jpeg

Top scope is the before mentioned Viper PST 5-25x50 SFP

Rifle is a Strike Eagle 5-25x56 FFP (my first FFP to try and play with) on a large frame .308 build. This is a 34mm tube which made mourning options interesting. I used an Areo mount. This has a Rainer Arms Ultra Match barrel in a Aero Enhanced set. Has been a solid <1” firearm with a Geissele G2S trigger. It got a Geissele SSA-E tonight from the 6.5 above, that one got a National Match High Speed.

Hope the scope size comparisons help.
 
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Trying to get some feelers out here, maybe I can get some pictures of your setups.

I'm trying to get a general consensus of what is the considered the maximum objective size and magnification for a small frame AR versus what is symmetrical for the size and weight.

Before I get hit with the Sponge Bob meme and "UsE ThE RiGhT ToOl For the JoB", slow your roll keyboard commando. I understand, and acknowledge that. If you have ever had a piece of kit that by the specs was the "right tool for the job" , but in practice was probably the worst choice due to size and weight considerations... You understand where I am at here, I'm looking for others experiences.

My setup in question is a 20 inch 6 ARC, looking at putting a 4-20 x 50mm scope on it. I don't want it banging into everything, and don't want to have Hubble attached to the top of my rail either.

Typical engagement is going to be from 50-750. Yes... you can shoot 1k at 8-10 power, doesn't mean I don't want PID at what I may be shooting at those ranges.

Any help is appreciated, stay safe.

I think you are vastly overcomplicating it.
If you are happy with the way the scope is on your rifle, that's all that matters.

One of the more common factors people are concerned with is the weight of the scope as compared to the weight of the rifle.

Being that the largest common use objective lens is around 56mm which fits fine on a small platform MSR, it's unlikely you'll run into something too big.

Usually, it's a matter of weight or overall length depending on if someone wants this to be a "handy" rifle as opposed to a range / target shooting setup.
 
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What is the rail used to mount these two scopes? I like that it lets you lower the scope to the bore line by using regular rings. Thanks in advance. I couldn't see markings on either one. Nice rigs.
Not sure what is in the pictures but PRI makes very similar riser mounts.
 
What is the rail used to mount these two scopes? I like that it lets you lower the scope to the bore line by using regular rings. Thanks in advance. I couldn't see markings on either one. Nice rigs.
GG&G They have a couple of different versions of the riser.



ggg-scout-rail-001.jpg





ggg-riser-01.jpg




......
 
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Thanks. That cost me my gun allowance. I like the MAD flip up sites. Had to get a set and a rail to try on a build.
 
@Flywheel If you are still looking, the Eotech Vudu 5-25X50 may be very close to what you're looking for. It's a super-short, under 12", under 30oz.s (barely) and a huge amount of vertical adjustment. Mine is on an old Genesco Armalite and it absolutely looks like it belongs there. Read the DLO's reviews and you will find he thinks it's a surprising performer particularly when viewed from a price/performance metric.

Just a casual check of prices will show you the scope is crazy cheap for what it delivers.

 
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20” 6.5 Grendel custom build… Arken SH4 Gen2 6-24x50 VPR MIL in their 34mm 20MOA AR mount. Works great. It’s a pretty hefty scope, but when mounted it’s not overly heavy or burdensome. Balances well, especially with a Can on the end. The extra magnification is nice, as well as the huge amount of elevation adjustment, thanks to the 34mm tube.

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Do you feel a NX8 2.5-20x50 SFP would be too much scope for a Sig MCX Spear Carbine 5.56? Not an AR but similar 🤷🏻‍♂️. I thought about smaller but I was hoping this NX8 could be dialed down enough for real close encounters and still suit my need to really dial in.
 
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Do you feel a NX8 2.5-20x50 SFP would be too much scope for a Sig MCX Spear Carbine 5.56? Not an AR but similar 🤷🏻‍♂️. I thought about smaller but I was hoping this NX8 could be dialed down enough for real close encounters and still suit my need to really dial in.
This setup would make it well-suited for mid-range performance and sufficient to handle shorter distances. 2.5x is less than ideal if you want to shoot less than 50 yards.
 
This setup would make it well-suited for mid-range performance and sufficient to handle shorter distances. 2.5x is less than ideal if you want to shoot less than 50 yards.

You can't really have 1 scope to do every possible thing that somebody may or may not want to do with an AR platform.

For 50 yards on out, really what you want is an LPVO in like 1-8 or 1-10
for closer than 50 yards, you really need a large holographic red dot sight.
(You could mix the two and have a small RDS and an LPVO)

If you are going to be 200 yards + mostly target shooting, then a standard scope with a low end somewhere in the 3 or above starts to make a lot of sense.

If this is a range gun with a long barrel and you are planning on being way out there, then get a scope with enough magnification to see your bullet misses.
 
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I’m planning on a holosun on a 45 degree mount as well. Figured the NX8 2.5-20x50 for if I don’t like it on the MCX I can throw it on a long range rifle. At its size it might be a good compromise. I have shot coyotes at 20 yards and closer with my NXS 5.5-20 so🤷🏻‍♂️