Rifle Scopes Trying to 'understand' what scope mount to use

[stintedAIR]

This is the first high end scope I've mounted on a rifle. The scope is a Schmidt & Bender 3-20x50 PMII. For reference, the diameter of the objective lense with a scope cap is just over 60mm. It's going on a Daniel Defense DD5V5. I've done countless searches, and it seems like everytime I find information, it's different than the last thing I just read. I started calling gun shops all over the state I'm in. Same thing, different answers depending on the person. I've been told a Burris Pepr is the way to go, because the scope is designed for a 20 moa cant and this is as high of quality as any. But then the next person I called said I needed something like a ERA-TAC Cantilever 1.46" high scope mount with 0 moa. He said unless I'm shooting past a mile, I don't want anything but a 0 moa cant. I'm honestly going insane trying to figure this out. Does anyone have any suggestions? I would really like to understand why a specific mount is better or worse than another. Appreciate the help in advance.

 

[b6graham]

Spuhr SP-4616

1.5" height cantilever 6mil/20moa mount meant for ARs

Call Mile High tomorrow. And explain this is what you want. And theyll get you taken care of.

You do want 20moa min rail. You do not want QD. You don't want a shit mount meant for $300 scopes. You DO want a spuhr for that scope

 

[stintedAIR]

Thanks @b6graham I will definitely call tomorrow.

 

[theLBC]

side question, or related.

do you want a canted mount, even if the scope you have has more dial range than you will need?
in other words, if you have 25 mils of adjustment, and you won't shoot past what would take 20 mils, is there still an advantage to a canted mount?
for example, my scope has 29 mils of adjustment (up), but i won't be able to hit anything much past 1000 yards (7.62x51mm 20" barrel) so i don't think i could even use all the range in the scope. do i still want a 20moa mount?
it makes sense to me is you have a scope without enough dial range (so you don't have to hold over) but otherwise?
sorry if this is a dumb question.

 

[b6graham]

side question, or related.

do you want a canted mount, even if the scope you have has more dial range than you will need?
in other words, if you have 25 mils of adjustment, and you won't shoot past what would take 20 mils, is there still an advantage to a canted mount?
for example, my scope has 29 mils of adjustment (up), but i won't be able to hit anything much past 1000 yards (7.62x51mm 20" barrel) so i don't think i could even use all the range in the scope. do i still want a 20moa mount?
it makes sense to me is you have a scope without enough dial range (so you don't have to hold over) but otherwise?
sorry if this is a dumb question.

Your 29 mils. Divide in roughly half. Well say 14 mils Left when you zero. Now add 6 mil(20moa) and you're at 20mil adjustment

Also. Being in the middle of the scope optically at 1k yards has its advantages

 

[stintedAIR]

@b6graham The idea behind the 20 moa base just clicked for me. Thanks again mate.

 

[theLBC]

Your 29 mils. Divide in roughly half. Well say 14 mils Left when you zero. Now add 6 mil(20moa) and you're at 20mil adjustment

Also. Being in the middle of the scope optically at 1k yards has its advantages

the Mark 5HD came from the factory with almost all the adjustment in one direction, and the turrets is marked 1-30 (3 rotations)
from zero stop there is only 5 clicks down (.5 mil).
is that very uncommon?

 

[Dthomas3523]

If your rail has 20moa already and not shooting past “normal” ranges, get rings or a 0 moa mount. If the rail is 0moa, you can go with 20moa mount

ARC or Spuhr are my go to. I don’t mess with anything else

Seekins are also g2g among other rings in that price range.

Pick one of those three and spend brain power on something else.

 

[theLBC]

@b6graham The idea behind the 20 moa base just clicked for me. Thanks again mate.

make sure you understand how your particular scope is designed. it may be like my leupold mark 5hd, in that it is marked for multiple rotations in one direction.

Schmidt Bender designed the 3-20x50 PM II for flexibility. The variable magnification from 3-20x permits universal use on a multitude of rifles and calibers while a 26 mil double turn locking elevation turret allows ample travel for the longest shots

The Double turn elevation turret provides a fine click adjustment value in addition to a large elevation adjustment. When the turret is rotated into the second revolution a small cylinder pops up on top of the turret which indicates to the user that the second turret revolution has been reached.

 

[theLBC]

nice scope, by the way!

 

[stintedAIR]

@theLBC Thanks mate

 

[stintedAIR]

Does anyone know of the top of their head what the canter of a DD5 rail is? Can't find it googling. I would guess it's 0 moa since its un-labeled, but I'm not sure.

 

[theLBC]

@theLBC Thanks mate

not that i am mr scope expert, but i didn't want you to spend $400 on a awesome mount if your scope isn't designed to "dial down" at least 6 mils. i am pretty sure that canted mount would not work for me.

 

[nrspence]

You may want to look at the JP one piece mount and rings...Very nice mount for a very nice scope.

 

[Danattherock]

I just looked at the product description and saw no mention as to whether it has a 0 or 20 MOA rail. I would call and verify that it is a 0 but that is likely. On that assumption I would get a 20 MOA one piece ~1.5 in mount. MPA and Aadmount make very high quality and reliable mounts. With the rifle you describe I would definitely not get a cheap mount, pepr are okay but they're made in China and I had one fail. Same for ADM. MPA and Aadmount are tested and reliable, yet more affordable than a Spuhr. Not knocking the Spuhr, just pointing out other very high quality mounts. I've got thousands of rounds through a one piece 1.5" JP mount that was about $200 on Midway. Lots of great options out there.

 

[stintedAIR]

Thanks for all the replies. Glad I found this community. I sent a message to Daniel Defense asking about the rail. I'll do some looking. Thanks again.

 

[theLBC]

Does anyone know of the top of their head what the canter of a DD5 rail is? Can't find it googling. I would guess it's 0 moa since its un-labeled, but I'm not sure.

i am sure somebody here will know.
i do know they make rifles with moa rails, like the Devil 5, but while they list the moa rail as a feature for the devil 5, they don't mention it for your rifle.

to me, 0 moa makes more sense, because a 20 moa rail might exclude high end tactical long range scopes like yours that are not designed to be zeroed "in the middle" of the adjustment range.

https://danieldefense.com/media/wysiwyg/magalog/Full-DD-Magalog-2019.pdf

or i could be off my nut and completely wrong. heck, i work on servers for a living.

 

[honuswagner]

I decided to go with the Mk 6 20 moa Leupold mount for my Mk5. I've been extremely happy.

Integral Mounting System (IMS®) | Leupold

A Leupold® Integral Mounting System (IMS®) has a durable monolithic, cantilever design that is formed from a single piece of bar stock, affixes securely to a picatinny rail, and built to withstand the most intense conditions.

www.leupold.com

 

[theLBC]

I just looked at the product description and saw no mention as to whether it has a 0 or 20 MOA rail. I would call and verify that it is a 0 but that is likely. On that assumption I would get a 20 MOA one piece ~1.5 in mount. MPA and Aadmount make very high quality and reliable mounts. With the rifle you describe I would definitely not get a cheap mount, pepr are okay but they're made in China and I had one fail. Same for ADM. MPA and Aadmount are tested and reliable, yet more affordable than a Spuhr. Not knocking the Spuhr, just pointing out other very high quality mounts. I've got thousands of rounds through a one piece 1.5" JP mount that was about $200 on Midway. Lots of great options out there.

are you sure he wants a 20 moa rail if he scope is designed with +24 mils adjustment for elevation and very little adjustment down?
he might have a 2 rotation model.

 

[Danattherock]

Yes

 

[Dthomas3523]

the Mark 5HD came from the factory with almost all the adjustment in one direction, and the turrets is marked 1-30 (3 rotations)
from zero stop there is only 5 clicks down (.5 mil).
is that very uncommon?

I’m not sure you understand how most modern turrets work.

You have total allowable elevations let’s say for example 34 mils. The mechanical center would be 17mil (ish).

Most turrets have a zero stop that is around .5 mil below zero, as there is hardly a reason to ever go below your 100yd zero.

Your actual available elevation after zero’d is determined by many things.

Let’s say it was at that 17 mil spot. You would be able to turn up 17mil, but you wil will only be able to go down .5mil to your zero stop.

If you needed to go down further than .5 to zero the rifle, you would loose. Your turret and set it on say 5 mils and re-tighten. Now you would be able to go down another 5 mils. Re-zero and you’re back to your .5 down and however many up.

 

[theLBC]

Yes

okay, you guys are the experts.

on my own setup, and mark 5hd 3.6-18x44, the turret is marked for 30 mils up, and i only have ~0.5 mils down from zero.
if you have the scope zeroed anywhere but near the end of the rotation, you would not get to 30.
if i had a 20 moa base, i don't think i could get a 100 yard zero.

 

[Dthomas3523]

okay, you guys are the experts.

on my own setup, and mark 5hd 3.6-18x44, the turret is marked for 30 mils up, and i only have ~0.5 mils down from zero.
if i had a 20 moa scope, i don't think i could get a 100 yard zero.

Turn your turret from zero to 15.

Loosen the turret screws and replace the cap to zero.

Now you’ll be able to go 15 up and 15 down (the zero stop at .5 won’t let you. But the 15 down is there if it’s needed.)

 

[theLBC]

Turn your turret from zero to 15.

Loosen the turret screws and replace the cap to zero.

Now you’ll be able to go 15 up and 15 down (the zero stop at .5 won’t let you. But the 15 down is there if it’s needed.)

i guess i am slow, so sorry.
i totally understand what you are saying.
what i am saying is that (with my scope), zero is nowhere near the middle of the travel. i don't think i need to borrow any moa because i probably can't hit anything that would need 27.5 mils anyway (which is how much i have left with zero at 100 yards.)

 

[Dthomas3523]

i guess i am slow, so sorry.
i totally understand what you are saying.
what i am saying is that (with my scope), zero is nowhere near the middle of the travel. i don't think i need to borrow any moa because i probably can't hit anything that would need 27.8 mils anyway.

Have you zero’d your rifle yet?

 

[theLBC]

Have you zero’d your rifle yet?

yes.

 

[Dthomas3523]

yes.

And how much “up” do you have left?

 

[theLBC]

And how much “up” do you have left?

actually 27.5 mils (not 27.8). out of stated 29.1 mils.
bobro engineering scar mount, if it matters, on a Scar 20S (pretty sure the rail isn't canted).

 

[Dthomas3523]

actually 27.5 mils (not 27.8). out of stated 29.1 mils.

This almost sounds like you have 40moa (12mils) built in somewhere.

I haven’t messed with a mk5 in a while, but don’t remember hearing about them zero’ing with 27 mils left without added inclination.

 

[theLBC]

This almost sounds like you have 40moa (12mils) built in somewhere.

I haven’t messed with a mk5 in a while, but don’t remember hearing about them zero’ing with 27 mils left without added inclination.

seems to me that leupold wouldn't (or shouldn't) brag about up to 29 mils of adjustment "for long range precision shooting" if half of it was useless "down", but again maybe i am way off and they expect folks to use an moa base or rail.

 

[Dthomas3523]

seems to me that leupold wouldn't (or shouldn't) brag about up to 29 mils of adjustment "for long range precision shooting" if half of it was useless "down", but again maybe i am off and they expect folks to use an moa base or rail.

All scope manufacturers advertise their total travel.

It’s up to the end user if they want/need to use it all. If so, you add inclination via rails and bases.

 

[theLBC]

All scope manufacturers advertise their total travel.

It’s up to the end user if they want/need to use it all. If so, you add inclination via rails and bases.

that definitely makes more sense, since i am unlikely to use more than 15 mils (and expect to hit anything smaller than a truck) ?

 

[Danattherock]

LBC, I wasn't trying to be short last night I got busy with the kids and forgot to come back and clarify my response. All my rifles have 20 moa rails and I've never had an optic where this was a problem. My assessment of the situation is very simple and I certainly don't claim to know everything about it. But 20 moa is 6 mil so using a 20 moa rail or 20 MOA mount on a 0 MOA rail allows me to be more towards the optical center of my glass when dialing out to extended ranges. The rationale is that the center of the glass is the purest, when compared to the far edges in either direction. So adding a 20 MOA rail or mount lets you look through the best part of your glass. There might be some mechanical benefits as well since you're not forcing the adjustment toward any far extreme.

 

[stintedAIR]

Just for an update. Got ahold of Daniel Defense. The DD5 line all have 0 moa rails.

 

[stintedAIR]

Does anyone have a suggestion on cantilever? EDIT~ Figured it out.

 

[chevy_man]

Does anyone have a suggestion on cantilever? EDIT~ Figured it out.

Just figured I'd toss this out there anyways.

I have gotten away with running rings on a2 stocks, but the cantilever is a must for an adjustable or a1 to get proper eye relief with most scopes.

 

[stintedAIR]

@chevyman368 Ya, that's what I was thinking. I'm going with a 60mm.

 

[stintedAIR]

Got my scope mounted today. Just wanted to say thanks to all those who helped, and for all the responses I got. I contacted schmidt and Bender, and they suggested a Eratac Super Short. Fits perfectly. Couldn't ask for anything better. The universal mount on top is well designed too.