Rifle Scopes Problem zeroing scope - elevation bottomed out

[Andy T]

I have the following setup:
AI AE MK II with Farrell 20 MOA base.
Leupold MK 6 3-18 mounted in Bobro 34mm mount. I flipped the mount around so that the levers are on the left side of the rifle. The mount does not have any cant.
Trying to zero at 100 yards. The POI is about 5 mil above POA and I am unable to move it lower, since the scope is at the bottom limit of the elevation travel. Has anybody else encountered a similar issue with MK 6? I am confused, as a few weeks ago, I was able to successfully zero Leupold MK4 6.5-20/M5 on the same rifle (except it was in ADM mount).
Is there such a thing as the mount being too high or could I have configured the MK6 incorrectly?
Thanks.
This is what it looks like:

 

[billyburl2]

Re: Problem zeroing scope - elevation bottomed out

Did you release the zero-stop? Other than, I would suggest a regular set of rings.

 

[Andy T]

Re: Problem zeroing scope - elevation bottomed out

This was going to be my follow up question - how do I release the zero stop? I read the manual, but am not sure if I got it right.
So far I get 15 mils from the bottom to the top.
Thanks!

 

[BobD]

Re: Problem zeroing scope - elevation bottomed out

Nice looking setup-
Hope this helps

You should have I believe around 100 moa when optically centered. Definitely sounds like this is your issue. As far as mounting, I would have suspected it was too high, but that would cause you the opposite issue (out of elevation at distance).

The ADM mount would have a lower centerline with your Mark 4 than the Bobro, even more so if you we're using their Recon SL mount. The Bobro is more than an inch and half to center and the Farrel bases I understand also run a bit high. The Bobro is really nicely suited for Ar platforms and the like that require the extra height.

Good luck, hope everything works out-

 

[Andy T]

Re: Problem zeroing scope - elevation bottomed out

Thanks BobD. I followed the instructions - although the ones for MK6 are a little different. However, I also can't figure out how to set the zero stop. I will get in touch with Leupold and see what they say.
BTW, is there such a thing as a scope that is mounted too high causing issues?

 

[insight3b]

Re: Problem zeroing scope - elevation bottomed out

I have been unable to zero any scope with a 20 MOA base point-of-aim point-of-impact at 100yds

 

[BobD]

Re: Problem zeroing scope - elevation bottomed out

Yes,
Mounting too high will cause you to run out of elevation at longer distances. Your sight picture will be too high and you will be shooting low. That's the purpose for adding the 20 moa base, it will allow you to have a lower sight picture. Also, when your scope is mounted too high and you are using elevation to compensate for it you are no longer looking through the center of the optic which is where you will have the best image. Additionally, at the limits of your elevation, you will severely limit your windage adjustments from the erector being too close to bottom.

Here's leupold manual for the Mark 6, I believe you have the M5B2 turrets

http://www.leupold.com/wp-content/uploads/2012/07/Tactical_Scope_Manual.pdf?9d7bd4

leupold

Again, hope everything works out. You've got a great combo there. Which reticle do you have ?

 

[Andy T]

Re: Problem zeroing scope - elevation bottomed out

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: insight3b</div><div class="ubbcode-body">I have been unable to zero any scope with a 20 MOA base point-of-aim point-of-impact at 100yds </div></div>
What scopes have you tried to zero? I was able to successfully zero MK4 6.5-20/M5 on the base at 100 yards.

Bob,
Thank you for the info. I have the H58 reticle. It's my first Horus reticle, and takes some getting used to - as it takes up almost all of the bottom half of the reticle on full power. I will give it some time before deciding if I want to trade it for something different.
I think the zero stop is operator head space more than anything and I will give Leupold a call on Wed.

 

[Spuhr]

Re: Problem zeroing scope - elevation bottomed out

Andy
I am pretty confident that your Shooting results would improve lots if the buttplate comes up at least ONE inch.
Easyest way of doing it is to swop to as lower rings as that would minimize heightdifferance betwen cheekpiece and buttplate.
Low buttplate leeds to high proneposition and there is no reason for that.

As far as I can see it QD is pointless on that gun.

Håkan

 

[Timo Turl]

Re: Problem zeroing scope - elevation bottomed out

The Farrelll mount is really tall, about 1cm it seems to a normal AI pic rail and on top of that you've added a high scope mount. Just wondering if it is all too high to give you enough room to come down enough. What is your scope height aboe the bore in inches ?

 

[Andy T]

Re: Problem zeroing scope - elevation bottomed out

Håkan,
Thank you for the information. I will look into getting AI Adj butt plate.
While it does appear a bit high, I think it's an issue with the zero stop in the scope itself. I tried on a Rem 700 with regular base, and I also couldn't boresight the bore/cross hair on a target about 75 yards away.
I am curious, how much lower would the Badger Ordnance, 1 piece, 1.49" mount be?
I generally prefer one piece mounts to rings.

 

[Petey]

Re: Problem zeroing scope - elevation bottomed out

I use the Badger Ordnance 1.49" mounts on a few 308 ARs; they're the perfect height for me on that platform. In my opinion, I think they'd be a bit high on a bolt gun.

For what it's worth, here's a picture of my Sako TRG22 and a Nightforce 'High' mount (1.125"). The only reason I went with a one-piece mount on this setup is because the Sako factory 0 MOA Picatinny rail is epoxied in place and I didn't want to screw around with the extreme hassle of removing it. With this mount, I'm gaining a needed 20 MOA for this little 20" 308 rifle. Even with a 1.125" mount you can see the amount of gap between the 50mm Nightforce F1 objective and the barrel, hence why I say the 1.49" Badger Ordnance is probably still a bit tall for you.

I'm not taking anything away from Håkan and his Spuhr mounts or even Badger Ordnance for that matter; it's just that this is the only bolt gun I have with a one-piece mount and a picture is worth a 1,000 words.

 

[Spuhr]

Re: Problem zeroing scope - elevation bottomed out

Andy, the extreme height of your mount is not causing the zero probleme.
I just meantioned the height as I belive its a problem for your shoooting.

Håkan

 

[Andy T]

Re: Problem zeroing scope - elevation bottomed out

I am happy to report that this was a case of "operator headspace". What I did is set the zero stop to the factory setting. To fix it, I simply unscrewed the set screw, and rotated the elevation dial up a revolution.
Now the scope is zeroed at 100 yards and on a 20 MOA base I have about 20 mils of up elevation adjustment and about 4 mils down.

 

[XTR]

Re: Problem zeroing scope - elevation bottomed out

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: insight3b</div><div class="ubbcode-body">I have been unable to zero any scope with a 20 MOA base point-of-aim point-of-impact at 100yds </div></div>

Wow, both of my NF scopes zero at 100 yards on my rifle mounted on <span style="text-decoration: underline">30MOA</span> bases. One has 8MOA left down the other has about 6.

 

[Andy T]

Re: Problem zeroing scope - elevation bottomed out

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: XTR</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: insight3b</div><div class="ubbcode-body">I have been unable to zero any scope with a 20 MOA base point-of-aim point-of-impact at 100yds </div></div>

Wow, both of my NF scopes zero at 100 yards on my rifle mounted on <span style="text-decoration: underline">30MOA</span> bases. One has 8MOA left down the other has about 6. </div></div>

The scope is fine. It was operator's error.