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Math check help on custom moa rings

Tesoro

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I have an Anschutz rodent rifle with a vx-2 4-12 AO and elevation turret add on. I have it zeroed for 100 with tac-22 which is my std round. But I would like to shoot it up to to 200 occasionally and play with the dial, holding for wind. I need to order a set of custom moa rings to do this.

The scope has 66 moa adjustment = 33 when reticle centered. For me to dial to 200 I need 19 moa more elevation with the 100yd zero but I bottom out after dialing 9 moa. This tells me my reticle is 24moa down from center at the 100yd zero or 9 moa from the bottom. This is maybe passable as reticle is roughly within 2/3 of adjustment range if I dont touch dial for anymore. 22 moa is 2/3 of total elevation and i'm at 24.

So If I took my rings off and replaced them with 20moa ones and didnt touch scope adjustment, then my 100 yd zero would now be 20 moa too high, If I dialed to get back to 100 yd zero, then the reticle center would be moved 20-24 moa = 4 moa lower than the 33 moa center.

Now with it re-zerod to 100 and then I dial to 200 I will need to lower reticle 19 moa. Reticle will be 19 + 4 moa for total of 24 below center. 2/3 of 33 is 22 so I am just out of the threshold of the 1/3-2/3 rule again.

Due to wind, temp and pressure I could find my self having to add a bit more elevation and be shooting with the reticle pretty far out of adjustment rule of 2/3.

So I figure I would be better off with 30 moa rings instead of the normal 20 moa. 30 moa rings would keep my reticle center safely in the center zone for the 100yd zero and be better positioned for 200 dialing at 14 moa below center.

Does this sound about right 'in theory'?
 
Wow...
My head hurts ttrying to keep up with that, this early in the morning. :D

If you need 19 MOA more, i'd get a 20 MOA base & be done with it.
$69 from EGW.

OR...

Swap scopes to one that has a MOA reticle and hold over.

Burris Fullfield E1, 4.5-14X42 with the "long range" (MOA) reticle runs about $200. Another big plus in my opinion is the side paralax adjustment vs the AO!

Crimson Trace Hardline 4-12X40 with MOA reticle sits about $450 but the glass is better than both the Burris & the VX2 you already have.
 
I guess looking at it in a simpler manner, if I need 19 more then with a 20moa it puts me in the same spot, where my reticle is lower than it ideally should be. But I still had to do the math to figure out how far the reticle was off center! So 30 moa would be better.

I have the new version vx-2 not the vx11 so the glass is improved, they say. fine duplex. It is ok for daylight shooting but I was married to it because I didnt know about the Crimson Trace. It would be nice to dial for wind. Not sure what the reticle subtension is? Be good practice for my centerfires to have both elevation and windage dialing. The hardline has 10 moa less travel than the vx-2 so I would be looking at a 40 moa ring set.
I want to keep the rifle sleek with a 1in tube.

ps: looks like this crimson trace is the only one with moa reticle but no parallax so gong.

 
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What is the elevation on the scope when zeroed at 100 yards?

Also, could you say more about the '2/3' limit you mentioned?
 
What is the elevation on the scope when zeroed at 100 yards?

Also, could you say more about the '2/3' limit you mentioned?

When zeroed at 100 it is 9 moa from bottoming out. re-thinking this I should really have the scope zeroed at 50 and then dial up to 200, because it has a zero stop so I cant go backwards from zero. Question is if I can even zero at 50 with 20-30 moa rings and 33 moa of travel with .22 ballistics!! have to do more math now.

I was always told that for regular leaf spring scopes with normal optics one should keep the reticle within the first 2/3'rds of the adjustment range. Might be an old wives tale, but the vx-2 dosent exactly have the dialing mechanics of a NF - just leaf springs.
 
Ah. The '2/3' guideline might have been to ensure there's some adjustment still available for windage.
=> You'll need to determine how much windage you might need at 200 and subtract that from the total reticle adjustment that the scope has [in your case, 66 MOA]. That would give you the number of MOA available for elevation from whichever distance it's zeroed at.
Personally, I don't like the idea of maxing out the travel - I'd want to leave a few MOA margin only because the clicks at the very max could be not linear.

With the sensitivity of 22lr to windage at 200 yards and the amount of elevation that will be needed, you might have to decide which is the primary distance you want to set the scope up for.
 
Sounds like a candidate for a set of Burris Signature Zee rings and a handful of various inserts and a 20 MOA rail. The possibilities are endless.

be the easiest but they are only in 30mm form what I see and beefy. for the same cost I can have my nice little 1in talley lightweights shaved down to whatever I finally figure out I need for moa. thanks tho
 
"Shave the Talley lightweights" - not being familiar w Talleys, could you please explain what part you are shaving? It may be a deal breaker.
 
PS. Burris does both 1" awa 30mm w inserts.
AFAIK, the 30mm have + & - 10s. That will give you the 20 moa needed ANNNNDDD never ring mark a scope.
You can also make some small windage adj by rotating the inserts but give up a bit of vertical. They are the berries.
 
The Burris Sig rings do come in 1". I have several. Inserts come in 5, 10, and 20. MOA. And you can put them in front and/or rear. As mentioned you will have lots of choices including rotating various amounts to include windage adjustments.

Frank
 
"Shave the Talley lightweights" - not being familiar w Talleys, could you please explain what part you are shaving? It may be a deal breaker.

A machinist does them, referred by Talley. Have to give him spacing measurements for mounting holes and he figures out the rest. I have to assume he takes material off the base bottom at matching angles. I didnt get to the point of asking how he does it.
My Annnie had a round 11mm dovetail that is tapped and talley makes a ring that fits on the hump but is screwed down. I would like to keep it simple and less bulky by not having to attach a 11m to 3/8 weaver adapter. I dont want to put on a rail because of possible-guaranteed - empty case interference.
D195CEB3-3503-4453-AB71-283E4E107406.jpeg
 
The Burris Sig rings do come in 1". I have several. Inserts come in 5, 10, and 20. MOA. And you can put them in front and/or rear. As mentioned you will have lots of choices including rotating various amounts to include windage adjustments.

Frank

The problem is how to attach them to my rifle. see pic I just posted.
 
The problem is how to attach them to my rifle. see pic I just posted.
Use a 20 MOA dovetail to weaver rail. If you don’t want the rail you can get the same Burris ring in 11mm dovetail and use the Burris inserts to get the elevation you want.
 

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Use a 20 MOA dovetail to weaver rail. If you don’t want the rail you can get the same Burris ring in 11mm dovetail and use the Burris inserts to get the elevation you want.
I looked up that ref# in your pic and no mention of moa +/- inserts? They just say they are for better alignment and grip?
 
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Ooph. With the rail on that Anschutz, this might get expensive.

If you use low rings with either of this rail, you should find a good end result.


 
The rings come with inserts. I don’t remember which MOA but you can purchase additional inserts .
I really like your idea of milling your ring bases. I looked at a .22 LR drop chart. Using standard Velocity ammo you will need approximately 20 MOA to go from a 100 yard zero to 200 yards .
 
The rings come with inserts. I don’t remember which MOA but you can purchase additional inserts .
I really like your idea of milling your ring bases. I looked at a .22 LR drop chart. Using standard Velocity ammo you will need approximately 20 MOA to go from a 100 yard zero to 200 yards .

I am calling Burris first thing in the amto see if they have and fit! Yes with 66 moa of adjustment, I can squeak by with 20moa rings with a 50 yd zero and dial to 200. It would be fun be able to dial to 300 with same 50 zero, but I would need a 30mm scope with more adj and 30 moa rings. Dont want that bulk so 200 it will be max.
 
Ooph. With the rail on that Anschutz, this might get expensive.

If you use low rings with either of this rail, you should find a good end result.



Be worse result I fear !! I have a 64 action and the rifle is a field gun with lightweight sporter barrel contour. It did not come with irons and bbl is not tapped. BUT this action was designed for irons and it ejects upwards at a high angle. When I put on the scope half the spent casings hit bottom and some landed back in the chamber area when cycling. This is so non-German!
I sent the bolt back to them and they tweaked the ejector so I dont get jams but I am sure a rail would give me a 1:25 jam rate as it does flip them the occasional one up higher.
I would have sold it but this is the only hunting/plinker I have owned that has put 5 shots in 3/4in at 100yds.

E6A35C6D-7D9F-4FAD-A295-028B09C3516B.jpeg
 
Be worse result I fear !! I have a 64 action and the rifle is a field gun with lightweight sporter barrel contour. It did not come with irons and bbl is not tapped. BUT this action was designed for irons and it ejects upwards at a high angle. When I put on the scope half the spent casings hit bottom and some landed back in the chamber area when cycling. This is so non-German!
I sent the bolt back to them and they tweaked the ejector so I dont get jams but I am sure a rail would give me a 1:25 jam rate as it does flip them the occasional one up higher.
I would have sold it but this is the only hunting/plinker I have owned that has put 5 shots in 3/4in at 100yds.

View attachment 1389511
You can cut the rail........
 

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