I am not understanding 20 MOA rings

Nimrod84

Handloader
Feb 20, 2017
376
2
Hi,

I just acquired a set of 20 moa Talley rings for a Sauer 100 rifle which uses Rem 700 rings. When changing over from 0 moa to the 20 moa rings, I had to move the crosshairs down. I was expecting to move the crosshairs up, due to the scope being angled down - https://warnescopemounts.com/wp-content ... 24x562.jpg

Can someone please let me know if the crosshairs moving down is correct when adding A 20 moa rail / rings? If my assumption was correct, what do I check before making phone calls? Orientation looks good, arrows point to the muzzle, and the 20 moa back base is taller than the 0 moa back base... Scope was zeroed at 100 yards at its mechanical zero in the 0 moa Tally rings, so the receiver I think is fine.

Thank you.
 
20 moa rings are used to gain more elevation correction. The amount you just corrected down is the amount you gained. you now have more room to dial up at longer ranges. If you had to move the crosshairs up you would be losing the amount you can move up for longer ranges.

Just look at your picture, the scope remains the same, the rifle now shoots 20 moa higher, so you have to adjust the scope down the 20 moa to be zeroed again.


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Still having a tough time with this.

Bullet impacted 23" or so low at 100 yards, was expecting bullet to hit high. Crosshairs moved down, bullet hits higher... Rather than reley on the turret markings, I pay attention to and move crosshairs. I have had turrets work in reverse. Ir seems that I lost 20 moa rather than gained it.
 
Typically if using 20 MOA rings, you are doing a 300yd zero too.
Not 100.

Normal scopes and normal rings run out of elevation about 500-600yards. The 20 MOA mounts give you more room to 900-1000 assuming you have a cartridge that can do that poke.


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Your scope can move about 40MOA.
Normal rings 0moa, would be roughly 20moa over and 20 MOA under on the 100 zero. That only give 20 MOA of elevation potential. Add the 20moa under your scope and you have to come down 20 MOA. Now you can travel up 40 MOA.

Just another way to say what bear said.


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Planning on my standard 250 yard zero. Have access to a 500 yard and 980-1280 yard range and am currently playing with a 6.5 Creedmoor. Trying to get the bugs worked out before making a 4hr drive to the long range. My 280 AI and M1's are a hoot up their.
 
Scope has 70 moa range, usable is about 60. When using 0 moa, the 30 is insuffient to barely feasible for 1000 yards with the 20" 6.5 Creed I am playing with. Issue is the 20 moa rings moved bullet impact down, I was expecting bullet impact up. Everything I have read says bullet should impact higher than before due to scope being angled down.

I appreciate the help, would like some real world experience to say if my experience is normal or not. If not normal I need to call Talley. If I am backwards than I need edumacating.
 
Are you sure you didn’t swap them and put the wrong one in the back


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Pretty sure. Long action Rem 700 base hole lengths are different.

I did check that screw holes were correct, longer in front and shorter spacing in the rear. I wanted to rule out a receiver issue.

Bases have arrows pointing to the muzzle and installed looks like the photos. I did take the scope off and verify everything mentioned. Rear 20 moa base is taller than the 0 moa base... Remounted the 0 moa bases and scope was giving a poa about 4" higher at 18 yards (basement).

Mounts are https://www.midwayusa.com/product/1781381814/. They advertise -
Arrows are engraved inside the ring to point toward muzzle.

Again, I do appreciate the help.

Editing for spelling, am on auto corkboard... I mean phone...
 
It was suggested that I shoot it at 175-200 yards and see where the bullet impact. If the impact is lower than the 100 yard impact, than I have a mechanical issue. If the impact is higher at 175-200 yards, than I'm getting an education.

Base height data looks fine to me, expecting a 0.3-0.35 height difference in the rear base - data is a bit rough due to curvature of the rings...
20 MOA 0 MOA
0.4 Front 0.4
0.54 Rear 0.515

Scope screw distances
Front about 0.87
Back about 0.6
 
It's correct. The rings tilted the scope up 20" at 100 yards. Now you need to dial it down 20" to get it back to where it was or where you want it.

JD338
 
JD338, do you mean scope angled down?

Thank you for the vote of confidence.

It still seems backwards to me - my thought process is as follows:
1. Crosshairs chase bullet impact.
2. Bullets hit low at extended range.
3. So how does moving my crosshairs down at 100 yards help me when I need additional downward crosshair movement as the range lengthens?

What part of my thinking is wrong? I would like to correct my bad thinking.

Hoping to shoot tomorrow morning or Wednesday morning and see how things shake out.
 
JJS405, thanks. Photo their is where I linked to in my OP.

That page is what I believe is telling me that I have a problem.
 
Basically the 20 mao rail or rings do the following. With zero rings or rails when the scope at set close to its mid points the point of sight is 2” or so over the bore of the rifle. To shoot a one hundred yard zero the scopes visual plane must go lower. By doing this the rifles bore path is pointing slightly up relative to the scope. To shoot further and have the bullets flight path intersect the line of sight of the scope you must elevate the barrel relative to the scope. This is initiated by pointing the scope down. Of course to get further and further ranges where to scopes sight plane intersects the bullets flight path you must keep moving the scope down which on your scopes dials is moving the point of impact up. So if you have a scope with 40 MOA of adjustment 20 moa in each direction from the center. With a zero rail or ring setup the most adjustment down you are getting is 20 moa. If you need 30 moa to get to 1,000 yds you run out of you ability to point down to elevate the flight path of the bullet so that intersects the scopes line of sight. When you put the 20 moa rings on it by default point the scope down 20 moa. So if we’re on a zero moa rail and you go to a 20 moa rail the bullet would hit 20 moa high at 100 yds. Because you now elevating the bullet’s path by that amount. To adjust you are going to move the point of impact down relative to the turrets. This is moving the elevation of the barrel up. In this case you are going to use the entire range of the scopes total adjustment to just get it close to zero. In which case you probably will be limited to a 300 yds zero. You simply can not get the impact point to move down far enough. But now you can use the full 40 moa adjustment of the scope to reach extreme ranges which require more elevations. So say you had a ring set up that have you a 100 yd zero. If you put on a 20 moa ring set the rifle is now pointing down 20 moa. The gun will shoot high really high in which case you might have a 1,000 yd zero depending on you cartridge. So you are going to have to turn your turrets point of impact down to bring it back to a reasonable zero. This confused the hell out of me as well. Just realize turrets adjustment are point of impact adjustments. The direction it Is moving the line of sight from the rifles bore is the opposite of point impact.


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Thanks for the help.

I called Talley while at the range this morning. After explaining my issue the rep said that it was not working as designed. I was on the phone for about 25 minutes with the rep and he had me run through a bunch of measurements and level checks. All measurements looked good, level checks were so-so and nothing was obiously out of place. Even so, I was instructed to send the rings back for an inspection. I told him that I would send the rings in after I tried a different scope.

I was thinking that if the rings aren't the issue than I might have damaged or messed up the scope while swapping rings. A new scope fixed the issue, I have about 8-10 MOA extra downward adjustment range now. Scope went wonky or I damaged it.

Thanks again guys.
 
What scope? I have a hard time believing the scope went wonky just by switching rings...I wont repeat what's already been said numerous times, but using 20 MOA bases will always make you dial down, that's how you gain the elevation in your scope. I zero all my personal rifles at 300 yards and this has always been the case. Have zeroed plenty of friends and customers at 100 or 200 as well, never had an issue there either. I think you're way overthinking the whole deal. Just zero at whatever distance you want, and start banging steel...
 
Also, you will notice if you're rifle is held perfectly still, looking through the scope, when you dial up, your crosshairs move down...This makes you raise the rifle essentially to now hit at longer ranges. Remember you're not sighting in your rifle, you're sighting in your scope...Best way I know how to explain it.
 
remingtonman_25_06":365tqzim said:
Also, you will notice if you're rifle is held perfectly still, looking through the scope, when you dial up, your crosshairs move down...This makes you raise the rifle essentially to now hit at longer ranges. Remember you're not sighting in your rifle, you're sighting in your scope...Best way I know how to explain it.

Bingo! Jorey nailed what I was going to post.

How did you make out with Talley?
 
Long post - will give all details here... I have been banging steel out to 1075ish yards to good effect. Personally went 3 for 3 at that range with a 5" group. Ammo was low so handed it off to my father, otherwise I would have liked to have seen what a 4th and 5th shoot would have opened it up to...

Answer 1: Scope was an Zeiss HD5 3-15x42. I have four of them and they mostly track properly. I have one that is suspect and it has been my backup scope - it has shown on two rifles a POI shift to the left when adjusting out past 400 yards.

Honestly, my first two HD5's were from the initial production run and one had an issue. One of the HD5's had old Conquest dials installed such that the dial's "up" moved the cross-hairs up, on the other scope the "up" moved the cross-hairs down. Zeiss swapped out the turrets on the one that moved the cross-hairs up; but that was after my father wasted a couple boxes of ammo trying to figure out why his scope wouldn't track...

That experience highlights why I think, write and talk in regards to how the reticles are moving. When people say they "dial up" or "dial down" - it takes me a bit to connect the context to what they mean. Long story in a sentence: post Conquest Zeiss and Leupold cap directions are for bullet impact - older Conquest hunting cap directions are for reticle movement; and I grew up with Leupold, Zeiss, Bushnell and Burris scopes... I still have and use the old Conquest scopes, so I'm still thinking in terms of reticle movement. I am not saying that my way is superior, just that if I don't think that way, things tend to go to crazy town in the field / range very quickly.

Answer 2: I swapped the initial HD5 out for the backup HD5 and everything has been good. Post swap out I noted that the initial scope had some light marks bordering on dents in it. So I'm guessing that when remounting it three times trying to figure out what was wrong, that I damaged it and or at least did not remounting directly on the marked possibly dented areas. If this is the case then the rings being partly on dents could result in the scope canting or moving in the rings.

Answer 2 continued: The other thing that caught my eye is that the scope eye piece has a very limited clearance from the ring base. If contact was made here it would tip the scope forward, or at least push the eye box up. I know the original rings were fine with the 1st scope but maybe the first scope was making contact on the 20 MOA rings without my knowledge, especially if it was sliding in the rings or had a slight cant to it due to the marks / dents. The 2nd scope seems to have a little more space between the eye-piece and 20 MOA ring base than I recall with the 1st scope.

Answer 3 to SJB358 - I was very happy with the 2nd and 3rd call in to Talley. First call, their was communication issues due to the rep talking about dialing up and dialing down and as noted earlier that isn't how I think. I simply couldn't get the dialog straightened out. I actually got the same rep on the 3rd phone call, and we primarily used the dialing up and down language for bullet impact. Both reps, 2nd and 3rd phone calls, agreed that the cross-hairs needed to move up when switching from the regular rings to the 20 MOA rings and that what I was seeing was not correct. On the 3rd phone call the rep offered for me to send the rings in for their inspection and he didn't think another scope would work. Me not wanting to waste time and money on what we both agreed were in-spec rings opted to try my backup - afformentioned 2nd - scope. As the 2nd scope performed as expected, I did not send the rings in for them the check.

Thanks again.
 
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