Scope height over bore for a bolt rifle

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I have a Savage Stealth 10 BA with a Vortex Razor HD gen II mounted in a LaRue 20 MOA QD mount. The height over bore is ~ 1.535" and I have trouble getting my head lined up correctly due to the height (I can, it's just a pain in the ass). I already have adjustable comb with the stock but that is an imperfect solution. I shoot this rifle out to 1,000 yards which is why it has a 20 MOA mount.

As a result, I am looking at a couple of mounting options and would like NES' $0.02.

What I am looking at:


  • ADM Recon SL low mount: 1.19" HOB
  • Badger 34mm rings: 1.0: HOB
  • Seekins ultra low rings: 0.92" HOB

Currently there is ~ 0.75" between the scope and the barrel with the existing mount (of 1.535" HOB) so there is plenty of space to lower the scope. I got a good deal on an EGW 20 MOA scope base so that is covered.

Thoughts, experiences, opinions, alternatives? Rings over bases? Advantages, disadvantages?
 
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white feather

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If you lower the scope, you will have to dial in more elevation... higher scope makes the rifle seem to shoot flatter. Why not raise the comb?
 
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If you lower the scope, you will have to dial in more elevation... higher scope makes the rifle seem to shoot flatter. Why not raise the comb?

Several reasons:

First, the scope has tons of elevation available. TONS
Second, I currently need to hold under at 100y and this will allow me to dial it (I actually benefit from "needing" more elevation).
Third, it isn't as comfortable for me to raise the comb: I can't seem to raise it enough to get behind the scope correctly.
 
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vicorjh

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I have a pair of Vortex PMR-34-100 (1 inch over base) that you can borrow if you'd like to test out the height. Planning to be at the PIG event on Saturday or HSC Friday in the morning...
 
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I have a pair of Vortex PMR-34-100 (1 inch over base) that you can borrow if you'd like to test out the height. Planning to be at the PIG event on Saturday or HSC Friday in the morning...

Really? That would be ideal!
 

mac1911

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No other than what problem you are having I like my scopes as low as I can get them. Then limit the amount of comb height needed. Even though the comb might have enough elevation to get you up to the scope this does not make it the most comfortable solution. I have adjustable combs on a few rifle and shotguns although mainly for the left to right adjust abilities.
Remember your scope is like a Front sight.
If you actual watch your reticle and it's going up your shot will go down.
This is how the 20moa mounts work.
The raise the rear of the scope lowering the reticle.
Having your scope mounted higher will not gain you any increase in elevation. It's the angle between the reticle and bore that needs to change.
As far as what ring height you need to do some figuring out there.
The better scope ring/mount manufactures give you the details of their scope ring/mount dimensions.
Try using clay to find what height works for you at the comb setting your comfortable with.
http://www.brownells.com/GunTech/Determining-Scope-Ring-Height/detail.htm?lid=10725
Now I use the clay on top of what ever mounts I'm going to use and then measure from the base to center line of the scope. I found most pic/weaver rail type rings are measured from bottom of base to center of ring.

If you have .75" between the front scope bell and barrel you should have several options for a lower mount.
I can only input on badger rings....very nice stuff I one set on my 30mm tube with 50mm front bell/objective. Sadly they don't make one as low as I would like for my application.
I have a set of the Burris XTR signature rings. Over kill for my application but are decent. Maybe not for the serious Long range crowd?
http://www.burrisoptics.com/mounting-systems/rings/xtr-signature-rings
I also like my vortex one piece mount.

If you had a 1" or 30mm tube I could send you a few ring sets to help determine scope height.
That's the worst part is ordering rings to find out they don't really fit.
Oh and if you use scope caps or some sort of slip on cover be sure to take that into consideration.
Also note the torque specs on the mounts/rails/rings they do not have to be that tight.
25inch pounds seems to be the average high on all the newer stuff I have. Very easy to over torque this stuff.

As for what's better rings/bases/one piece ?
I try to go by my dad's wisdom. The least amount of parts/screws and moving parts is ideal but then you need to do what works for you.
 
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Thanks Mac, I do have a torque driver. I will see how the Vortex 1" rings feel and go from there. That should be a solid reference point.


Does anyone have $0.02 on rings versus solid mounts? QD?
 

mac1911

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Thanks Mac, I do have a torque driver. I will see how the Vortex 1" rings feel and go from there. That should be a solid reference point.


Does anyone have $0.02 on rings versus solid mounts? QD?
Again I need to stress I have some better rings and scopes on my 22s and do not get past 200 yards but a few times a year.
I have the Burris zee rings with QD and they are very good my scope/rifle I use them on I switch from scope to match sights often. They hold zero and stay tight.
I would install the 20moa mount on the rifle itself.
Stacking a 20moa base on top of the mount is just adding another level of "fail" IMHO.
If you need QD mounts get them. If not I personally would go with out. This is dependant on many factors.
I prefer rings over one piece mounts you will have more adjustability. My vortex mount only gives me about 5/8-3/4" adjustment before the rings hit the turret section in either direction with rings I can set the rings where ever I like and I like to try and get the rings out towards the scope objectives. Just for a little added support.
Also since your shooting out to 1000 yards your going to want to set up your scope to have more of your adjustment range in the lower to mid range of your turrets. Most scopes will loose precision in adjustments as you get to the out limits of the erectors travel.

I just looked on vortex web sight do they not have mounts any more?
Any way I don't shoot long range out to 1000 yards but I do push my pellet guns out to 125 yards and my 22s to 200.
 
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Mountain

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I have the one piece Vortex mount for my service rifle, but primarily for the offset. I'm using rings on my 6.5CM AR. I don't think there's really such a difference between mounts and rings so long as everything is properly mounted.

I realize I'm stating the obvious, but watch for things that might interfere when using low rings / mounts, such as scope caps etc.

Another fyi regarding ring torque:

I had some tracking issues last winter and sent my PST back to Vortex. They determined the scope was fine and proved it by firing it on one of the tech's service rifles. Couple calls back and forth and we figured out that by torquing to the high end of the spec I had caused the binding via over-torquing. I think those wrenches are not always that accurate. I re-mounted at the lower end of spec and have had no issues since. Great service from Vortex & they were very nice at telling me it was user error, LOL.
 
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LaRue mount, 1.535":




Vortex rings courtesy vicorjh, 1":




My thought is to trim that overhang off the rail/base and get the lower 0.92" rings. I do want to get behind the scope how it is but I don't want to damage Jay's BRAND NEW rings he lent me. Thank you, this is so much easier but I didn't know they were new!!
 
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vicorjh

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Feel free to use them in the field if you'd like, you're not going to damage the rings (avoid lapping them, though). I don't care if they get scratches or scrapes, so have at it.

Curious, how's the eye relief with the way the scope is sitting? 3-4 inches?
 
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Feel free to use them in the field if you'd like, you're not going to damage the rings (avoid lapping them, though). I don't care if they get scratches or scrapes, so have at it.

Curious, how's the eye relief with the way the scope is sitting? 3-4 inches?

I will put the top of the rings on and let you know.
 
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The scope is much easier for me to get behind now.



The eye relief is constant throughout the zoom range, something that was a problem with the previous mounting.
 

mac1911

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The scope is much easier for me to get behind now.



The eye relief is constant throughout the zoom range, something that was a problem with the previous mounting.
can you get a lower profile mount ? I forgot my friends son is deep into savage rifles. had to call him
He says hes really digging his DNZ one piece as it bolts directly to the rifle. Hes only running a 44mm objective 30mm tube on that rifle. He says hes got a new toy a Stiener M5Xi Military 5-25x56 style scope with the Stiener rings ontop of his 6.5 BA. has no idea who made the base its a lower profile than the others he has and picked it up at a match....
 
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Not really. I think that has as much to do with the bbl shape. The mount itself is concave and only 1/4" at the middle. You wouldn't want it much thinner I don't think.

Seeking does make 0.92" rings that might fit if I trim the front overhang off that base/rail.
 

mac1911

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Not really. I think that has as much to do with the bbl shape. The mount itself is concave and only 1/4" at the middle. You wouldn't want it much thinner I don't think.

Seeking does make 0.92" rings that might fit if I trim the front overhang off that base/rail.
Nice your on your way.... I understand wanting the scope in the right position. Heck even with iron sights on most rilfes if I plop my head down fow a nice solid cheek weld I am usually looking at the back of the bolt.

Im also one to do what ever it takes.. Heres just a few examples on my pellet guns cause they are handy.
I would love to go much lower but the loading port for the pellet would be tough to load
 
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vicorjh

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Once thing for certain, the height is looking more reasonable with the lower rings on your rifle.

At this point, if it were me, I'd probably check the cheek pad height while maintaining a point of aim out to your maximum distance + maximum zoom or thereabouts. If you still have a comfortable amount of adjustment available on the cheek pad at distance (maintaining a good relationship to the eyebox), you've checked that box off and could perhaps consider the 0.92 with the base modification.

The further out you go, as you adjust for hold-off, the image gets projected progressively lower and as a result you may end up positioning your eye lower in relation to the objective. On one particular rifle/scope setup I was trying out (30mm tube + 44mm objective), the rings were very low. Cheek pad height was fine out to 400 yards or so. 600-1000 yards, I ran out of cheek pad height adjustment and had to position my eye below (and subsequently behind) the cheek rest such that I was buffering the recoil with my cheek bone. Not terribly enjoyable. In other words, test the setup against how you're shooting as a data point.

Shaving off a half inch on the height should certainly help with any cant error as well. With a 0.08 difference between 1.00 and 0.92, it would interesting to understand the benefit in relation to cant. Does someone have a general rule of thumb (without having to derive the math)?
 
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I don't have any space available to readily test eye relief for 1,000 yards so I will need to live with testing in the basement. I am thinking about ordering the 0.92" rings to see how it sits but I can't imagine that 0.08" makes that much of a difference. Right now, the cheek pad is raised a fair bit so I do have room to drop the comb height.

 
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What is your length of pull on the rifle? It looks really long with that side-fold adapter on there.
With the LOP fairly long, that seems to be pushing your scope further back than would be normal. Therefore causing your interference issue at the front of the rail.
 
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Vortex Precision low height rings:






There isn't a ton of difference compared to the 1" rings Jay lent me (which will go in the mail this week) but the price was the same and I wanted this mounted as low as I could go. It is now much easier for me to get behind so mission accomplished.
 
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badger or seekins or the high end vortex rings (rebranded seekins rings), its all a wash. I wouldn't bother paying the extra for the badger though at this point. I have, and they are no better than the seekins/vortex rings. I haven't used a mount on a bolt gun so I can't speak to those. I would go vortex/seekins and have more money left for ammo/barrels.

EDIT: For some reason tapatalk only showed the OP so I thought this hadn't been replied to at all, nvm 3 pages lol.
 
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badger or seekins or the high end vortex rings (rebranded seekins rings), its all a wash. I wouldn't bother paying the extra for the badger though at this point. I have, and they are no better than the seekins/vortex rings. I haven't used a mount on a bolt gun so I can't speak to those. I would go vortex/seekins and have more money left for ammo/barrels.

EDIT: For some reason tapatalk only showed the OP so I thought this hadn't been replied to at all, nvm 3 pages lol.

Thanks for playing Josh, lmao. I thought about Badger but didn't like the single cross bolt on the rail mount. The Vortex look great and same price as Seekins only they match the scope.
 
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