Rifle Scopes Wil this elev fix work as well as I think?

[JimGnitecki]

I use the same Nightforce 12-42 x 56 Benchrest scope on both my TRG 42 bolt rifle in 338 Lapua and my LMT MWSE semi auto 308. I do this by having the scope mounted via Nightforce Lightweight rings onto a Larue quick disconnect Pictanny spacer. This has worked well up to now. The Larue QD spacer is dead-on in returning to POI, and the only adjustment required at 100 yard zero is to crank the windage left a bit when going from the LMT to the TRG.

This has worked well at 100 yards through 500 yards.

Yesterday though, a friend spotted for me as I tried 1000 yards for the first time with the TRG. I ran waaaay out of elevation range. The "Shooter' app on my iPhone said I needed 31 MOA of additional height (versus the 00 yard setting), and I could only crank in 15 MOA before I ran out of adjustment. There are only 10 MOA of holdover markings on the scope below the zero line, so I was 6 MOA short, and actually ran out of physical sight picture before I could hold over enough!

I checked the specs and zero setting on the scope. The total internal elevation range is 40 MOA and the 100 yard zero is at 25 MOA up from the bottom, leaving only the 15 MOA range left to work with.

Here is what I am considering doing to solve the problem:

I can replace the Evolution Gun Works scope rail, which has zero MOA built in, with a 20 MOA rail. That would make the new zero on the TRG (without touching the zero adjustment) about 750 yards. Dialing in 11 more MOA would give me my 1000 yard elevation, and I'd still have 4 more MOA to go. I don't need more than that, as our local range tops out at 1000 yards.

To get back to 100 yards, I'd need to drop 20 MOA from the 750 zero, and since the scope has 25 MOA available below that setting, I should be fine.

When switching between the TRG and the LMT, I would always get the setting back to the "25 MOA above bottom" zero setting (which is 750 yards on the TRG because of its 20 MOA rail. and 100 yards on the LMT with its zero MOA rail). I would need to crank the same windage correction in as I currently do.

Will this work as well as I think it will, or have I missed something?

If it will work, what special arrangements if any must be made to order a rail from Near in Canada, because of the border crossing? Or, is the Near 20 degree rail also available through a U.S. dealer? I like the fact that the Near is so precisely made and uses ALL the slots in the TRG receiver to locate ad secure the rail.

Jim G

 

[buffybuster]

Re: Wil this elev fix work as well as I think?

My advice:

Buy a dedicated scope for each rifle. You have too much of an "erector set" system going on. Tolerance stack is going to work against you.

12-42X has a very limited amount of travel, it's going to quite difficult be able to dial beyond 1Kyds and still keep a 100yd zero. If you're OK with having a 600yd zero, then it will work, otherwise sell it and apply that money towards two scopes. What you're attempting to do is going to cost you $300 in mounts.

 

[pdogsbeware]

Re: Wil this elev fix work as well as I think?

Try the Burris Signature rings. I know they aren't "tactical", but they hold and they will do what you need for very little money.

Just in case you don't know what they are, they have inserts that hold the scope tube within the rings. You can put different thickness inserts in to get the same effect as a canted base, but for only $50. And you can tailor it pretty well, like if you only wanted 15 MOA cant instead of 20, for example. You can be pretty selective in how much you want to adjust them.

 

[McLarenross]

Re: Wil this elev fix work as well as I think?

What your talking about sounds like it will work to me. But I would consider what Buffy said. You could sell the Nightforce and apply ~$500 to that and have 2 SS 5-20xs. If your dead set on swapping the NF between guns Id also look at a 22MOA Badger riser for the LMT so that your zeros will still be pretty close to each other and you can run the gas gun out to 1000 now too.

 

[JimGnitecki]

Re: Wil this elev fix work as well as I think?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pdogsbeware</div><div class="ubbcode-body">Try the Burris Signature rings. I know they aren't "tactical", but they hold and they will do what you need for very little money.

Just in case you don't know what they are, they have inserts that hold the scope tube within the rings. You can put different thickness inserts in to get the same effect as a canted base, but for only $50. And you can tailor it pretty well, like if you only wanted 15 MOA cant instead of 20, for example. You can be pretty selective in how much you want to adjust them. </div></div>

Replacing the rail on the TRG sounds better to me - more robust, and fewer points of potential movement. I agree the cost of the Burris rings would be lower, but I really value robustness.

Jim G

 

[JimGnitecki]

Re: Wil this elev fix work as well as I think?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: McLarenRoss</div><div class="ubbcode-body">What your talking about sounds like it will work to me. But I would consider what Buffy said. You could sell the Nightforce and apply ~$500 to that and have 2 SS 5-20xs. If your dead set on swapping the NF between guns Id also look at a 22MOA Badger riser for the LMT so that your zeros will still be pretty close to each other and you can run the gas gun out to 1000 now too. </div></div>

I don't want to downgrade my scope by trading it for 2 less costly ones. I like the scope a lot.

While adding a 20 MOA riser to the LMT would make it "more like the TRG" (it would operate in the same MOA range), it would add yet another interface between the Larue QD and the LMT rail that is built into the rifle upper, and that hurts robustness.

If I really want the LMT to also be compatible with 1000 yard distances (and I 'm not sure I do, as it has the 16" barrel, and also chrome lined versus s.s.), the solution is to trade the Nightforce scope for another Nightforce scope with more internal elevation range. There are a number of models with 60 or even 100 degrees of internal elevation range.

That might be a better solution, since it keeps both rifles in the same zero range, and probably won't cost much more to make the trade than to buy a 20 MOA rail of good quality for the TRG.

Perhaps. I need to find out what such a trade would cost me.

Jim G

 

[X-fan]

Re: Wil this elev fix work as well as I think?

I love my 12-42 BRs. It is my fave on my 6mmbr and F-class rifles, but they would be painful on a 338 Lapua or something you could be shooting at any distance with.

The other think is they are hardly a NXS in terms of durability...I think the Burris rings could be a good stop gap for you until you can get an NXS with more travel...What I would do.

In terms of big scopes I prefer the 8-32X with its 65MOA internal for something I might steer a all ranges. The other issue you might run into is with only 5 MOA left in the scope you wont have much windage adjustment.

The Near stuff is as good as it gets...Actually it might be the very best.
You will be happy with the quality if you go that route.

 

[JimGnitecki]

Re: Wil this elev fix work as well as I think?

I found a better solution: a Larue quick disconnect LT 112 scope mount.

This is a one-piece combination of rings, Picatinny base, 20 MOA built in angle, and quick disconnect.

This allows me to retain the same exact setup as I have been, to use on both rifles, but raising the zero range frm 100 to 750 yards on the TRG 338 Lapua, and something less than that on the LMT (approx 675 yards I think).

So:

- Works on BOTH rifles
- More rigid (1 piece)
- Extends range to over 1000 yards on the TRG and close to that for the LMT (and my local range only goes to 1000 yards)
- Allows me to keep one GOOD scope versus 2 mediocre ones

Happy.

Jim G

 

[X-fan]

Re: Wil this elev fix work as well as I think?

There ya go.

 

[steve123]

Re: Wil this elev fix work as well as I think?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JimGnitecki</div><div class="ubbcode-body">I found a better solution: a Larue quick disconnect LT 112 scope mount.

This is a one-piece combination of rings, Picatinny base, 20 MOA built in angle, and quick disconnect.

This allows me to retain the same exact setup as I have been, to use on both rifles, but raising the zero range frm 100 to 750 yards on the TRG 338 Lapua, and something less than that on the LMT (approx 675 yards I think).

So:

- Works on BOTH rifles
- More rigid (1 piece)
- Extends range to over 1000 yards on the TRG and close to that for the LMT (and my local range only goes to 1000 yards)
- Allows me to keep one GOOD scope versus 2 mediocre ones

Happy.

Jim G


</div></div>

In the long run I think you'd be <span style="font-size: 11pt">"much much happier"</span>with getting into a scope like the NF 5.5-22 (100MOA travel) or similar scope with the LT112. Having the extra travel is infinitely better than high mag.

A couple reasons why...

1. A lot of times there is a degradation of resolution when a scope is nearly all the way up or down in it's travel. Scope tracking issues are usually the most exaggerated when a scope is sighted in at it's lowest travel then used near it's highest travel.

2. Sighting in a rifle at 675Y to 750Y for shooting inside of 1000Y, to put it bluntly is, well, silly??? I'm not trying to be a jerk here Jim. It's kinda like stuffing a size 10 foot into a size 9 shoe. Can it be done?, yes. It is a good idea, no and for many reasons!

 

[JimGnitecki]

Re: Wil this elev fix work as well as I think?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: steve123</div><div class="ubbcode-body">

In the long run I think you'd be <span style="font-size: 11pt">"much much happier"</span>with getting into a scope like the NF 5.5-22 (100MOA travel) or similar scope with the LT112. Having the extra travel is infinitely better than high mag.

A couple reasons why...

1. A lot of times there is a degradation of resolution when a scope is nearly all the way up or down in it's travel. Scope tracking issues are usually the most exaggerated when a scope is sighted in at it's lowest travel then used near it's highest travel.

2. Sighting in a rifle at 675Y to 750Y for shooting inside of 1000Y, to put it bluntly is, well, silly??? I'm not trying to be a jerk here Jim. It's kinda like stuffing a size 10 foot into a size 9 shoe. Can it be done?, yes. It is a good idea, no and for many reasons!






</div></div>

I'm really not seeing the problem here, Steve. In fact, I think the new setup is pretty ideal!

What I mean is that with the Larue rail in place, my scope will operate in an ideal range. It will be 5 MOA above its lowest internal setting at 100 yards, and that's surely the shortest range I would use the scope at versus the BUIS. At 1000 yards, it will be 4 or 5 MOA below its upper internal elevation limit, and I physically cannot shoot more than 1000 yards since my local range tops out at 1000. I cannot imagine a more ideal "range" to be in.

As for accuracy at the limits, hey, my friend who was spotting for me when I was trying for the 1000 yards said that my shots were all right ON in windage, and within 3 feet of the small target gong on elevation - the errors ine elvation being a function of my trying to shoot while using elevation offset that extended below the physical image in the reticle! (I was holding over so much that the target gong and the stand it was on were both just below the image visible to me!). When I backed off to 500 yards, which meant 21 MOA lower setting, or ABOUT WHERE THE 1000 YARD SETTING WILL BE WITH THE RAIL(!), I hit on the VERY first shot. Nightforce scopes are pretty accurate on tracking.

I suspect that there will be limitaitons on windage adjustments near the limits, but hey, we're talking 338 Lapua here, not 308 or 223.

And, I really, really like not having to drag around a spotting scope, and having to break my position to look through one, when firing groups for ammunition testing. That 42 power makes the bullet holes very easy to see at 250 yards.

Jim G

 

[steve123]

Re: Wil this elev fix work as well as I think?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JimGnitecki</div><div class="ubbcode-body">

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">

In the long run I think you'd be <span style="font-size: 11pt">"much much happier"</span>with getting into a scope like the NF 5.5-22 (100MOA travel) or similar scope with the LT112. Having the extra travel is infinitely better than high mag.

A couple reasons why...

1. A lot of times there is a degradation of resolution when a scope is nearly all the way up or down in it's travel. Scope tracking issues are usually the most exaggerated when a scope is sighted in at it's lowest travel then used near it's highest travel.

2. Sighting in a rifle at 675Y to 750Y for shooting inside of 1000Y, to put it bluntly is, well, silly??? I'm not trying to be a jerk here Jim. It's kinda like stuffing a size 10 foot into a size 9 shoe. Can it be done?, yes. It is a good idea, no and for many reasons!






</div></div>

I'm really not seeing the problem here, Steve. In fact, I think the new setup is pretty ideal!

What I mean is that with the Larue rail in place, my scope will operate in an ideal range. It will be 5 MOA above its lowest internal setting at 100 yards, and that's surely the shortest range I would use the scope at versus the BUIS. At 1000 yards, it will be 4 or 5 MOA below its upper internal elevation limit, and I physically cannot shoot more than 1000 yards since my local range tops out at 1000. I cannot imagine a more ideal "range" to be in.

As for accuracy at the limits, hey, my friend who was spotting for me when I was trying for the 1000 yards said that my shots were all right ON in windage, and within 3 feet of the small target gong on elevation - the errors ine elvation being a function of my trying to shoot while using elevation offset that extended below the physical image in the reticle! (I was holding over so much that the target gong and the stand it was on were both just below the image visible to me!). When I backed off to 500 yards, which meant 21 MOA lower setting, or ABOUT WHERE THE 1000 YARD SETTING WILL BE WITH THE RAIL(!), I hit on the VERY first shot. Nightforce scopes are pretty accurate on tracking.

I suspect that there will be limitaitons on windage adjustments near the limits, but hey, we're talking 338 Lapua here, not 308 or 223.

And, I really, really like not having to drag around a spotting scope, and having to break my position to look through one, when firing groups for ammunition testing. That 42 power makes the bullet holes very easy to see at 250 yards.

Jim G </div></div>

Oh, I see what you are saying. I didn't read the top post just this one. Hopefully it'll work out OK then. Hopefully the situation will be a size 10 foot in a smallish size 10 shoe.

 

[kombar]

Re: Wil this elev fix work as well as I think?

Or you could just turn the mag down until your reticle subtends the required amount. According to my slide rule that will happen at around 26x. At 12x you should have 35 MOA of holdover on the reticle.

 

[JimGnitecki]

Re: Wil this elev fix work as well as I think?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Kombar</div><div class="ubbcode-body">Or you could just turn the mag down until your reticle subtends the required amount. According to my slide rule that will happen at around 26x. At 12x you should have 35 MOA of holdover on the reticle. </div></div>

I THINK I understand what you are saying, but let me try stating it so you can correct me where I go wrong.

The reticle markings on my 2nd focal plane scope are 2 MOA calibrated at 22x (not at 42x), with 20 MOA total markings below the crosshairs. On a 2nd focal plane reticle though, the markings subtend different amounts of MOA as the magnificaiton is avried from the magnificaiton at which they were calibrated (22x in this case). This is because the reticle stays the same size while the magnification changes, so each marking covers more MOA at lower magnificaitons and fewer MOA at higher magnificaitons.

So, at 12x magnification, each marking covers 22/12 x 2 MOA = 3.66 MOA instead of 2 MOA.

So, at 1000 yards, with 12x magnification, using the TEN "2 MOA at 22x" markings below the crosshairs, I actually have 3.66 x 10 = 36.6 MOA of holdover available, if I leave the scope zeroed at 100 yards?

When I was trying to shoot the steel at 1000 yards, at 42x, the ten markings subtended only 22/42 x 20 MOA = 10.5 MOA? I had already dialed in all remaining 40-25 = 15 MOA of internal elevation. So, if I have done the calculations correctly, it's no wonder I could not get onto the target within the view available in the scope, since 15 MOA internal adjsutment plus 10.5 holdover = only 25.5 MOA total. The Shooter iPhone app said that if I assumed a muzzle velocity of 2500 fps (a guess based on the loading manual numbers available at minimum and maximum powder loads), I needed 31.X MOA. So, I would need to hold over another 6 MOA BELOW the bottom-most marking, which is way below the view available in the scope.

Have I calculated this correctly?

Jim G

 

[kombar]

Re: Wil this elev fix work as well as I think?

Your calculations look right to me. I was calculating based on your original post which suggested the total holdover on the reticle at 42x was 10 MOA, which means my numbers are a little off.

 

[JimGnitecki]

Re: Wil this elev fix work as well as I think?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Kombar</div><div class="ubbcode-body">Your calculations look right to me. I was calculating based on your original post which suggested the total holdover on the reticle at 42x was 10 MOA, which means my numbers are a little off. </div></div>

Yes, I was already allowing for the reduction in holdover markings, from 20 MOA at 22x to only a bit over 10 MOA at 42x. I foolishly never thought about the fact that I could have reduced magnification to some intermediate value between 42x and 22x, and been able to hold the holdover markings on the target. Heck, 22x might even have been sufficient, and then I would have had the full 20 MOA range of markings PLUS no calculation to do do in my head (each minor marking at 22x is exactly 2 MOA, and each major one is 5 MOA).

Jim G