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Discussion Starter · #1 ·
Hey Guys - New to this forum and Long Range Shooting

I recently picked up an RPR in .338 Lapua with a Leupold 5HD 5-25-56mm optic and am wondering which scope rings you guys are running on a similar setup?

I understand the Picatinny rail has 30MOA and my scope has plenty of adjustments as well.

Would any of the LaRue Tactical QD Rifle Mounts work? I was looking at the one they made for the 50BMG but it has an additional 30MOA of cant. Would this be too much for clearance?

Any help or advice would be great. I was ideally looking for a quick disconnect option so I can swap optics easily.

Thank you,

Scott
 

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I recently picked up an RPR in .338 Lapua with a Leupold 5HD 5-25-56mm optic and am wondering which scope rings you guys are running on a similar setup?

Would any of the LaRue Tactical QD Rifle Mounts work? I was looking at the one they made for the 50BMG but it has an additional 30MOA of cant. Would this be too much for clearance?
Scott, I don’t think I’d be to concerned with clearance, I’d be more concerned with the optical performance of the scope. Your scope has 120 MOA of vertical, in other words 60 up and 60 down. The RPR has a 30MOA rail, the rings you mentioned have an additional 30 MOA, 30 + 30 = 60. Your scope has 60 MOA of adjustment from optical center, do you see where I’m going with this? If you can zero your scope if will be bottomed out. Scopes are at their worst optically when used at their extreme end of adjustment, be it high or low. For a longer explanation as to why I said this research it.

I run a Nightforce 5.5x22-56 on my RPR, it sits on top of a set of Vortex PMR rings, (about $130). The ring height is 1.45”, (that’s what you’ll need for a 56 objective) and it puts my scope about 3/16 off the cage as I call it. These are not quick release rings as I don’t see the need to ever take the scope off.

My Precision has a 20MOA rail and it’s chambered in 6.5 CM, my Nightforce has 100MOA of vertical. My zero is set at 200yds and I still have 69MOA of unused vertical.....with my hand loads it only takes a 34MOA correction to reach 1000yds. In other words your 30MOA rail combined with Leupold’s 120MOA of vertical will be more than enough for you to run long range.

Welcome to the forum.
 

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The new Ruger Precision handguard leaves about 1/8” difference between the top of the optic rail and the top of the handguard - basically the exact clearance you want for the optic bell. So the math to figure your clearance is easy - just be sure the objective bell is at or above the pic rail, and you’ll have clearance above the handguard.

So here’s the math:

The 5HD 5-25x56 has an objective bell diameter of 2.54”.

Rings are typically measured in 2 ways:

If the manufacturer lists their scope ring heights to be “top of rail to center of tube” as most do, then you need 1.27” rings, or higher. (2.54 / 2 = 1.27”)

If the manufacturer lists their ring heights as “top of rail to bottom of tube,” then you need 0.581” or higher. (A 35mm tube is 1.378”, so 2.54 / 2 - 1.378 / 2 = 0.581)

An extra 30moa off-set would dip your objective bell by about .1”, assuming the ring height specification is given for the REAR of the mount, not the front. (30moa is .5 degrees, figure there’s about 12” of the 15.7” 5HD in front of the rear ring. So sin(.5) * 12 = 0.105”). If the FRONT of the ring is what the manufacturer gives as its specification, then the additional dip is only 0.05”.

60moa total elevation might not allow you to zero at 100 yards. The 5HD has 120moa of internal adjustment, meaning 60 above and below optical center. Putting the optic ~2.2” over the bore, and given ~2.3” of total gravitational drop compensation by 100yrds for a 338 Lapua round, you’re talking about ~55.5moa “up” to zero at 100yrds, out of a maximum of 60. It SHOULD work, but only if the internal adjustment spec is perfect and you get a true 60 up on the scope. This set up does maximize your range potential with the rifle, as you should be able to dial to about 2200 yards before even holding in the reticle. IF, only if, it works. If it doesn’t, you might have to hold under for anything inside 200-300 yards. If it does work, it’s the perfect optic system to match the cartridge and rifle for maximized range capability.
 

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..........or if you don’t feel like doing the math, (I didn’t) find a set of rings you like/want and call the manufacturer. I called Vortex and told what rifle I had and what scope I planned on using on top. My next question was “what do you have to offer, keeping the scope as low as possible?” I also called Nightforce but they were considerably higher in price.

Most of the better ring makers already know what rings work with what rifle/scope combo. It will eliminate the aggravation factor.
 

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I apologize if I presume doing this level of basic addition and subtraction isn’t aggravating for anyone capable of understanding similar math involved in shooting long range.

But, they say half of American’s can’t balance their personal finances, so maybe I presume too much.
 

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Discussion Starter · #6 ·
Scott, I don’t think I’d be to concerned with clearance, I’d be more concerned with the optical performance of the scope. Your scope has 120 MOA of vertical, in other words 60 up and 60 down. The RPR has a 30MOA rail, the rings you mentioned have an additional 30 MOA, 30 + 30 = 60. Your scope has 60 MOA of adjustment from optical center, do you see where I’m going with this? If you can zero your scope if will be bottomed out. Scopes are at their worst optically when used at their extreme end of adjustment, be it high or low. For a longer explanation as to why I said this research it.

I run a Nightforce 5.5x22-56 on my RPR, it sits on top of a set of Vortex PMR rings, (about $130). The ring height is 1.45”, (that’s what you’ll need for a 56 objective) and it puts my scope about 3/16 off the cage as I call it. These are not quick release rings as I don’t see the need to ever take the scope off.

My Precision has a 20MOA rail and it’s chambered in 6.5 CM, my Nightforce has 100MOA of vertical. My zero is set at 200yds and I still have 69MOA of unused vertical.....with my hand loads it only takes a 34MOA correction to reach 1000yds. In other words your 30MOA rail combined with Leupold’s 120MOA of vertical will be more than enough for you to run long range.

Welcome to the forum.
Thanks for the very detailed response. I ended up buying this one as it didnt have any additional MOA angle.

Will this work ok?

LaRue Tactical SPR / M4 Scope Mount QD LT104
Places the centerline 1.5" above the top rail
 

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Scott, you’ll be fine with that ring/mount combination, that is a pricey set, at least $200 I’m guessing.

Now if you already know this you can tell me to shut up. After you mount your scope and prior to bore sighting you need to drop the elevation on your scope 30MOA, that will compensate for your 30MOA rail and create a new optical center. I only say that because I know an experienced shooter who didn’t do this and he was scratching his head for awhile....until someone told him.

I think you’re making a wise choice rather than trying to add another 30MOA via rings. A friend shoots a .338, albeit not an RPR, but he runs a 30 rail and his scope I believe has 140 of vertical total. He’s pushing a 250 Nolser Accubond at around 2900fps at muzzle and he needs right at an 81MOA correction for 1760yds, (a mile).

With your 30MOA rail and the 120MOA your scope has you should still have 90MOA of vertical left after you zero your rifle. Worst case scenario you can always move up to a 40MOA rail if you want to run out farther.

Let us know how it works out for ya.
 

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Discussion Starter · #8 ·
Scott, you’ll be fine with that ring/mount combination, that is a pricey set, at least $200 I’m guessing.

Now if you already know this you can tell me to shut up. After you mount your scope and prior to bore sighting you need to drop the elevation on your scope 30MOA, that will compensate for your 30MOA rail and create a new optical center. I only say that because I know an experienced shooter who didn’t do this and he was scratching his head for awhile....until someone told him.

I think you’re making a wise choice rather than trying to add another 30MOA via rings. A friend shoots a .338, albeit not an RPR, but he runs a 30 rail and his scope I believe has 140 of vertical total. He’s pushing a 250 Nolser Accubond at around 2900fps at muzzle and he needs right at an 81MOA correction for 1760yds, (a mile).

With your 30MOA rail and the 120MOA your scope has you should still have 90MOA of vertical left after you zero your rifle. Worst case scenario you can always move up to a 40MOA rail if you want to run out farther.

Let us know how it works out for ya.
Thank you sir - I'm glad you told me as I wouldn't have known that lol. Truth be told this setup is probably way overkill for my experience level in long-range precision shooting but I wanted something I could grow into and I'm hungry to learn.

Anyways, when you say drop the elevation on my scope 30MOA prior to bore sighting, do you mean by using the elevation adjustment knob before I zero it at 100 yards to start?
 

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Anyways, when you say drop the elevation on my scope 30MOA prior to bore sighting, do you mean by using the elevation adjustment knob before I zero it at 100 yards to start?
Correct. Try to picture this, lets say you have a 0 rail on your rifle and you zero your scope at 100yds. Now you take your scope off and replace the 0 rail with a 30 rail and remount the scope. In theory if you went back out and shot your rifle at 100yds, making no adjustments to the scope it would now print 30” higher when holding your cross hairs on the bulls eye. If it was a 20 rail you’d drop it 20MOA, a 40 rail the drop would be 40MOA. Dropping it 30MAO will offset the 30 rail.

Scopes generally come from the factory set at the optical center .......unless someone goobered with it. If you’re in doubt crank it all the way up then count down 60MOA, that should put you at the scopes optical center. Then drop it another 30MOA after mounting.
 

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Discussion Starter · #11 ·
Correct. Try to picture this, lets say you have a 0 rail on your rifle and you zero your scope at 100yds. Now you take your scope off and replace the 0 rail with a 30 rail and remount the scope. In theory if you went back out and shot your rifle at 100yds, making no adjustments to the scope it would now print 30” higher when holding your cross hairs on the bulls eye. If it was a 20 rail you’d drop it 20MOA, a 40 rail the drop would be 40MOA. Dropping it 30MAO will offset the 30 rail.

Scopes generally come from the factory set at the optical center .......unless someone goobered with it. If you’re in doubt crank it all the way up then count down 60MOA, that should put you at the scopes optical center. Then drop it another 30MOA after mounting.
Thanks a lot, Mark for that simple response. Totally makes sense.

One more question regarding my Illuminated Tremor 3 Recticle in my Leupold. I don't have a reference of what other Illuminated optics look like when actually looking down them but I played around with the ocular lens adjustment to try and make everything tack sharp and it gets pretty sharp but it's still a bit blurry. Is this just due to how busy this recticle is or should I absolutely be able to see every single little tick mark tack sharp?
 

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One more question regarding my Illuminated Tremor 3 Recticle in my Leupold. I don't have a reference of what other Illuminated optics look like when actually looking down them but I played around with the ocular lens adjustment to try and make everything tack sharp and it gets pretty sharp but it's still a bit blurry. Is this just due to how busy this recticle is or should I absolutely be able to see every single little tick mark tack sharp?
Scott, your reticle should be sharp regardless of how busy it is. I’m not familiar with the reticle in your Leupold but my Nightforce reticle is loaded up with reference points.

A common mistake people make when adjusting the ocular is to look through it while adjusting. Try using the sky or a white wall as a back drop, (I prefer a wall) when adjusting. If it’s not sharp the instant you look through it, pull off and adjust the ocular and repeat. Do this as many times as needed to make it crisp. If you look at the reticle when making your adjustments your eye will trick you into thinking it’s sharp only to find the next time look through it that it’s not........ask me how I know.
 

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Discussion Starter · #14 ·
Scott, your reticle should be sharp regardless of how busy it is. I’m not familiar with the reticle in your Leupold but my Nightforce reticle is loaded up with reference points.

A common mistake people make when adjusting the ocular is to look through it while adjusting. Try using the sky or a white wall as a backdrop, (I prefer a wall) when adjusting. If it’s not sharp the instant you look through it, pull off and adjust the ocular and repeat. Do this as many times as needed to make it crisp. If you look at the reticle when making your adjustments your eye will trick you into thinking it’s sharp only to find the next time look through it that it’s not........ask me how I know.
So after playing around with the ocular adjustment the crosshair and markings themselves are tack sharp but when I turn on the illumination at night its a bit difficult to make out some of the markings and sometimes the red bleeds into other markers or fills the entire eyepiece. I thought the adjustment for the illumination was for brightness but I guess it's for illuminating only certain points. I just want to make sure I didn't get a damaged version or something. Again I have no reference point for an illuminated reticle

Thanks-
 
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