M*CARBO Brotherhood

Optic eye relief

Goblin: That’s very helpful information–that a rail mount is available from G G &G. In your opinion is $106 reasonable, or would you suggest a different brand?

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the AD-BC-3 from AMERICAN DEFENSE MANUFACTURING fits my ACOG, moves it back perfect. I am going to check tonight, because the base is remove-able from the scope, and i have the Burris Prism, which i think has the same size base as the vortec you have if so their mount will work perfect. let me do a lil research… Im going to “phone a friend” that has a spitfire, have him bring it over so we can see what fits what… how far you need to go back, do you have a flip down rear sight, it might be tomorrow for i get every thing together, but if you got the time, i will find it,.:+1:

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can you take a picture? if so flip the scope upside down, and take a picture looking at the very bottom of the base…

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Goblin:
I really appreciate all this information, especially the picture and taking the effort to speak to a friend with the Spitfire. I have the upgraded McCarbo rear peep sight. I’ll be looking for your suggestion.

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@Gunther22G It appears @GOBLIN (Buck) has largely answered your question. I do not know if it will work in your situation, but I found a scope mount that cantilevers 3 inches rather than the normal 2 inches. You can see it and a Lion Gears Cantilever mount I tried to use together to put an inexpensive 1-4 scope with decent but not great eye relief on the S2K at this link:


As I feared, the Lion Gears mount with its single point would not hold and loosened after only a few rounds. I replaced it with a cantilever Fyland mount that lacks a quick release lever but is still quickly installed and removed. A photo of that setup is below. You will note that it moves the scope very close to your eye while still mounting on the stock S2K rail. I took this setup to the range this morning. The Fyland mount began to loosen after about 75 rounds but a quick retighten and everything returned to zero, including the cheap red/green dot on top of the scope. Given the extent of cantilever and the stresses involved, I think making it through 75 rounds was pretty good. The iron sights are also visible through the base of the mount, so three sighting options are available.

The Fyland cantilever mount can be found at the link below. I added regular and lock washers to the locking bolts which probably helped it avoid becoming loose for as long as it did. I also replaced the single locking side plate with two shorter ones from other mounts.

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@JoeFridaySays Hey with the short rail section on the Mcarbo mount, he is going to have to run single point on a cantilever, another case of "vibra/loc tite is your friend, or tighten the lever up. to the point you can barely lock it. Lion gears is in the running

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Joe Friday & Goblin: So far I see 3 contenders–G G & G, Fryland & mention of Lion Gears. My Spitfire is just 5" long and weighs 15oz. It’s much closer in size to Goblin’s scope than Joe Friday’s much bigger & heavier scope. Goblin’s G G & G cantilever brings his Spitfire-sized scope at about the same position as the rear peep sight, a perfect distance. So do you guys think if I went with the G G & G I’d have the same problem as Joe Friday where I’d have to be retightening every trip to the range? Is the G G & G a quick release mount as it seems to be shown on their website? Also please explain why the Spitfire “with the short rail section on the McCarbo mount ( ) is going to have to run a single point on a cantilever” and therefore have to deal with loosening.

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For his application, the Lion Gears mount might do the trick. There was just too much cantilever and weight with what I was doing for the single point mount to hold. This was the first Lion Gears mount I purchased and I do not like having the locking end swing freely like it does. I already have crushed one spring and lost another.

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So Lion Gears is the pick of the litter? I see it on Amazon for $7.99. I see one buyer that had a bolt shear after 5 rounds, called it “absolute garbage.” The other 25 users seemed to like it, though. I still don’t see from Goblin’s picture of the G G & G whether the setup would be a mistake, whether I could expect it to shake itself loose.

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@Goblin how many slots are on the MCarbo mount? This mount has two attachment points and uses only 3 slots - there are a few others like it on Amazon. Since @Gunther22G will be using the optic mount he does not need a QD Mount.

They make longer ones but I cannot tell in the time I have how many slots they need to mount.

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Goblin & Joe Friday: My conclusion at this point is that I’ll be bringing the Sub 2000, the McCarbo mount and the Vortex Spitfire to my very able gunsmith and figure out a solution. Thanks very much for your suggestions, which I’ll be passing along to him.

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@JoeFridaySays 3 slots 4 bumps Brian, and so far Lion gear is the best contender. I single point mounted the ACOG on the MCarbo Mount,heaviest thing i have, and rolled 100rnds thru it front point didnt budge… just to test overloading on the mount.

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I thought about this myself. The issue I see is that most of the prisizm scopes are 2 to 3 inch eye relief and have a small eye box. The added buttstock creates even greater distance. If one wanted a quick deploy weapon to get off snap shots in just about any orientation than the red dot seems to be the best solution.

I sighted mine at 100 yards. I think ots the max yardage where the sub 2k will perform in quick fire situations.

Now I know I can reach out to 200 yards but those shots will be slow fire and well practiced with Kentucky windage applied.

I also just removed my front and rear sights.
The sight picture is to busy for me I a red dot.

Now it’s a clear field of view and easy target acquisition.

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It is definitely Doable if you want to mount a full scope for more accurate 50 and 100 yard shooting, but it’s a game of millimeters making sure you get the scope ocular back far enough for proper Eye relief and enough height to clear the rear sight if you have a stock rear sight…
I did this on the cheap and it holds zero and has adequate accuracy out to 100 yards. Folding is not important to me.

Montstrum adjustable riser set at the lowest height, approximately 0.6 inches, qd release. Monstrum cantilever scope mount flipped backwards, moves rear of scope back 2 1/2 inches. Full length 12 inch scope - cheap pinty 3-9x40eg $30. All accessories purchased on Amazon prime, total accessory cost < $60.

If I bring my nose up to the rear of the collar nut, then I am in the sweet spot exactly at 3 inches eye relief to the scope ocular, which is clearing the rear side and just in front of the safety, at the level of the rear of the ejection port. With the added height, no longer have to do chicken neck maneuver and in a much more comfortable position, with more of a jaw weld then cheek weld to the buffer tube.

Works well, and to top off the set up, the scope mount has pic rail slots on the top of the two rings, though I’m not currently using them. Used a cheap Amazon tacfun 45° offset pic rail mount mounted all the way forward on the top rail. mounted a 1X red dot in the 1 o’clock position for close quarter distances.

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This view from the right side so that you can see the red dot mounted far forward at the 1 o’clock position with an offset pic rail mount. I had tried an M lok offset mount but could not get the M lok to stay put

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I would guess that you either leave the rifle extended, or else unbolt the mount for the big scope every time you plan to fold it. As for the small red dot, that looks like it stays in place, opened or closed.

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The quickest and easiest would be a compact red dot on the McCarbo swing away optic mount. My problem is right eye issues. The best solution for using my 3x 5" 15 oz Spitfire Vortex sight may be the Lions Gear on top of the McCarbo optic mount. If that proves too awkward, I may end up going to the 1x red dot and shoot two-eyed.

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Yes x 3

Qd release on riser gives quick detach option if you want to fold or ditch the scope for iron sights.

I live in a state where carry is prohibited so foldability has no practical use.

The only downside’s on this set up are the extra bulk and the modest increase in weight on a rifle that is only 4 1/2 pounds, and not being able to use the iron sights. But my iron sights came out of the factory way off and adjusting them bottomed out the height so an alternate to the iron sights was a plus in my case.

The keys to this set up are measure everything down to the millimeter and plan ahead. Make sure you have enough height to clear the rear sight unless you’re using a foldable one; use a riser + cantilever mount. Use a full length scope & reversed cantilever mount to get enough rear work extension so the eye relief is just right

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I find that using the red dot allows me to shoot with my corrective lens on. I have astigmatism snd use tri focals. With glassed on the dot appears as a dot without it is a bizarre shape. It has something to do with how our eyes process the light.

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