PDA

View Full Version : Sharing an optic from AR to Bolt guns... AR+Riser?



Noodles
02-05-12, 21:58
So.... I know this has come up a couple times, and I think I have a solution, but I wanted to check in to see if anyone had any personal experience with this.

My goal, to share an high-end medium-power (2x-10x or so) optic across a few platforms. A mega monolithic AR, a Model Seven, a 700, Ruger Scout mounted traditionally, another AR, a handi-rifle, etc. I figure if I can do that, it makes more $$ sense right now to do that and swap between guns.

My plan, to use a LaRue LT-101 riser at .625" on the mega AR and a good QD medium ring set at Medium (.875) giving me medium on my bolt guns with rails and 1.5" on the AR.


Things I'm not sure about...

Since I have unlimited rail space on the Mega monolithic upper, I don't need a cantilevered mount correct?

Obviously I'm probably going to be limited by medium height to a 42mm or smaller objective? This is fine, but I feel like I'm forgetting something here.

I hate when scopes block the charging handle on an AR, in fact, nothing says amateur any louder to me. If I didn't have a monolithic rail, I would need a cantilevered riser right? Does anyone make one of those?

I definitely want mildot or some version of because BDC between 22lr, 357, 69/77gr 556, 300blk, and 308 is NOT going to happen even if I did get a scope with custom turrets. Correct?

I'm looking at tactical milling or gen2-3 mildot for the scope. By my thoughts, if I could find a scope with a zero stop, I could easily switch between guns with just a positive offset (like sight in and lock for the lowest zero, swap scope to another gun and just know the offset for that gun is 4 clicks up). Is zero stop required for this? Am I thinking this through correctly?


As time goes on I'd like to get dedicated optics for guns that need them, but for instance, the handi-rifle won't be a go-to gun, and I don't feel like buying a nightforce or whatever optic for a $300 gun.

I feel like if it works to have (in theory) one scope, I'd like to give it a go. Is this a terrible idea?

anthony1
02-06-12, 02:47
lts not impossible but it will be a MAJOR pain in the ass switching a scope between that many rifles. Your also gonna be wasting alot of ammo just trying to figure out where your at and confirming zero.

I'd just pick one rifle and leave it there. I dont take my scopes off my bolt rifles unless l absolutely have to. Even just taking a scope on and off the SAME rifle will usually require a slight adjustment, switching between a bunch of rifles l'd guess your gonna spend more time zeroing your scope than actually shooting.

skullworks
02-06-12, 07:05
The "easy" way of doing it is to get 1-piece Picatinny bases for all the guns then get a really good set of rings such as LaRue, or (if you had the money) a Spuhr ISMS (http://www.tnvc.com/?catalog=1&s=spuhr)-mount, then decide which rifle will be your primary rifle. Zero the scope to the preferred range when mounted to your primary rifle, then make dope cards for each of the other rifles - beginning with what adjustment you need to do from the "Primary Zero" to get to that particular rifle's zero.

skullworks
02-06-12, 07:10
[Double Tap - please delete!]

Noodles
02-06-12, 13:22
Using a larue mount on my big bolt gun, I've found the QD to actually be quite reliable. Surprisingly so, like .5" at 100y. I'm not terribly concerned about that.

More so, with the zeroing like you guys mentioned anthony. I guess one thing I completely overlooked was POI. These guns are almost all suppressed and while looking at zero stops and knowing the gun offset for elevation, I just completely overlooked left/right variance. It would be so much simpler if all my guns shot perfectly straight every shot!!! :D

Ok, so I'll give in that even knowing the vertical and horizontal offset between even two guns, -even on dope cards- it's still going to be different per ammo batch, elevation, temp, etc. So +1 and -1.25 mils might work today, probably not tomorrow.

I feel like I was using the same rifle for 6 months and another for 3 and another for 3 with no switching in between this would be fine.


In this case.... I guess what I'll do is look at guns I won't use even remotely at the same time and consider sharing between those.

Bummer.

Noodles
02-06-12, 13:32
I guess one thing I can take away from this however is that by going with a monolithic AR rail, I can get away from needing a cantilevered scope base. Meaning I can buy a riser, and use a set of medium rings that will still work on bolt guns with pic bases.

Now I'll look look to see if someone makes a cantilevered riser, then at least I can swap between bolt guns, monolithics, and normal railed ARs.

Noodles
02-06-12, 13:47
http://www.gggaz.com/gs-1-optical-mounting-rail.html

I'll have to consider pros and cons of something like this. Might be useful if someone already owns a nice QD medium ring set and doesn't want to buy a QD cantilevered mount that only works on ARs.

skullworks
02-08-12, 05:43
Actually, Todd Hodnett from Accuacy 1st (http://www.accuracy1stdg.com/) recommends using the same scope (as long as it's not a scope with a ballistic reticle) on multiple rifles for just the reason you noted in your original post (ie better to splurge on one really good scope than 6-7 half decent ones).

And since Mr. Hodnett has forgotten more about long range shooting than I'll ever know...

Going back to my previous comment; get good one-piece Picatinny bases for all the rifles, then mount the scope in the best mount you can find (LaRue if you want QD-capability, Spuhr if you don't). Then just keep track of what adjustments need to be made from the "primary zero" from one platform to the other.

Noodles
02-08-12, 17:10
I think what I'll do is get the riser for the monolithic and a set of medium QD rings that work on my bolt actions with pic bases and I'll see.

Instead of going crazy on a mid range scope with illumination and zero stops, ffp, tactical mil dot, etc, I'll just get a SS 3x9 that has a lot of those features minus the illumination. Worst case that scope stays on one of the guns forever. Best case, it's shared between a couple.

Dano5326
02-09-12, 09:45
One optic is doable so long as you have a chance to confirm zero after mounting. And, you could certainly buy better glass that way.

Picatinny interface would be the logical one. With a monolithic upper a cantilever not req'd. I'm not familiar with the other rifles or offsets required.

Depending on differing zeros you may be able to tic mark the dials to represent different weps, ready reference, all on one optic.

If you intend on shooting past 600m, esp in varying altitudes, the Horus methodolgy spanks mildot or BDC's.

FromMyColdDeadHand
02-10-12, 01:11
We need some pics to show what you guys are thinking of.

skullworks
02-10-12, 07:12
Check out the beginning of the second DVD of Magpul Dynamics Art of the Precision Rifle and you'll see exactly what we're talking about. ;)

Just screw the scope into on of these (image courtesy of - and hotlinked to - LaRue Tactical (http://www.laruetactical.com/larue-tactical-obr-qd-scope-mount)):
http://www.laruetactical.com/sites/default/files/imagecache/product_detail/pa051327.jpg
LaRue Tactical OBR QD Scope Mount, LT111 (http://www.laruetactical.com/larue-tactical-obr-qd-scope-mount)

Or one of these (image courtesy of - and hotlinked to - TNVC (http://www.tnvc.com/shop/spuhr-30mm-ideal-scope-mount-system-isms/)):
http://www.tnvc.com/shop/images/8206/?400,250,3996860967
Spuhr 30mm Ideal Scope Mount System ISMS (http://www.tnvc.com/shop/spuhr-30mm-ideal-scope-mount-system-isms/)

Then get 1-piece Picatinny bases for the rifles that need them (and with the elevation needed for that particular rifle).

For Remington Seven (image courtesy of - and hotlinked to - EGW (http://www.egwguns.com/remington-bolt-action/hd-remington-xp-100-model-7-picatinny-rail-scope-mount/)):
http://www.egwguns.com/images/products/80230-80231.jpg
HD Remington XP 100, Model 7 Picatinny Rail Scope Mount (http://www.egwguns.com/remington-bolt-action/hd-remington-xp-100-model-7-picatinny-rail-scope-mount/)

rob_s
02-10-12, 07:21
One potential challenge is ring spacing. You *may* be able to mitigate that on the bolt-action rifles with a one-piece picatinny rail section, but then you're also likely covering up the action making single-round loading more difficult.

It sounds like it's doable, and if you have more time than money it might even work out in the end, and you might be able to write down your clicks/settings to be able to account for different zeros.

skullworks
02-10-12, 07:42
For single-cartridge feeding it would obviously be preferable to use 2-piece bases and separate rings, but given the fact that it's quite common for the tapped holes in the receivers to be misaligned,* I would advise against going down that route if you want to swap the scope between multiple platforms.



* Which can be fixed by truing the action and re-drilling and taping the holes in a mill for 8-40 instead of 6-48, but then that is custom rifle work with a hefty price tag attached.

rob_s
02-10-12, 07:48
For single-cartridge feeding it would obviously be preferable to use 2-piece bases and separate rings, but given the fact that it's quite common for the tapped holes in the receivers to be misaligned,* I would advise against going down that route if you want to swap the scope between multiple platforms.



* Which can be fixed by truing the action and re-drilling and taping the holes in a mill for 8-40 instead of 6-48, but then that is custom rifle work with a hefty price tag attached.

I don't know a lot about this, so I'm asking...

Will that matter once the picatinny rail sections are installed? I can see how the mounting holes might be out of alignment with the true barrel center, or worse with one another, but with QD levers would it still mount up the same way every time anyway?

skullworks
02-10-12, 07:51
Using a 1-piece base alleviates the problem of the holes being misaligned. The "problem" with using quality rings on misaligned 2-piece bases is that they either won't lock because the misalignment is too great or (worse) you will put a lot of strain on the scope.

lifebreath
02-10-12, 11:08
Two other one-piece mount options:

Bobro (http://swfa.com/Bobro-Precision-Optic-34mm-Mount-P51893.aspx):

http://swfa.com/images/bobb10300340.jpg

and Near Alphamount (http://www.nearmfg.com/products.htm):

http://www.nearmfg.com/images/products/trg42_right.jpg

skullworks
02-10-12, 12:48
No disrespect intended, but... I couldn't find a price for the NEAR Mfg mount, but for the money Bobro charge I'd fork over the extra $ and get the Spuhr for the extra features (or save some and get the LaRue for the same as the Bobro).

lifebreath
02-10-12, 13:51
No disrespect intended, but... I couldn't find a price for the NEAR Mfg mount, but for the money Bobro charge I'd fork over the extra $ and get the Spuhr for the extra features (or save some and get the LaRue for the same as the Bobro).

The Near website is a little "rustic," but the product is top notch. The Alphamount runs $325. You just call Richard and tell him what you want and he tells you what you need!

The only advantage to the Bobro is that it's a QD lever lockup with good return to zero, which might be useful for your purposes. The 34mm dual lever version is new, but they don't yet have the same design in other sizes.

The Spuhr or Alphamount would be my choice, but the LeRue or Bobro offer the QD.

One other top grade one-piece mount is the AADMOUNT (http://www.aadmount.com/) which is about $250:

http://www.aadmount.com/PICT0005.JPG

USAF maddog
02-22-12, 23:59
I also want to one really good scope versus two or three cheap ones. I am getting a LEUpold VXIII 4-12 with 50 objective in a target scope. I am concerned though about 50 mm objective raising the the scope so high. Have never used such a scope but like the idea of more light being utilized in early mornings. My application is using a LARUE mount on both a 6.5 Grendel and 6.5 Creedmore LMT.

Noodles
02-23-12, 11:30
I also want to one really good scope versus two or three cheap ones. I am getting a LEUpold VXIII 4-12 with 50 objective in a target scope. I am concerned though about 50 mm objective raising the the scope so high. Have never used such a scope but like the idea of more light being utilized in early mornings. My application is using a LARUE mount on both a 6.5 Grendel and 6.5 Creedmore LMT.

Yea, I'm not sure about a 50mm scope on an AR. Compared to other guns the AR has the worst/pickiest scope height and cheek weld issues.

However, you're going AR to AR (sortof) so the cantilevered mount will work fine as long as 50mm fits both.

mkmckinley
03-14-12, 20:38
It seems to me that with an AR most mounts put the scope 1.5" or so above the rail. That's the height of the standard irons and what provides about the right cheek weld for most shooters. If 1.5" is what you're going to use anyway why not mount the largest scope that will fit, which ends up being about 50mm.

FromMyColdDeadHand
03-16-12, 01:17
I have a Premier 3-15x50 on my 40X in an AICS with on a Badger Pic rail and mounted in an AI 28MOA mount. I'm talking to MileHigh about getting a AE mkIII and was planning on just moving the scope over from the trainer to the main rifle, just waiting to get the scratch together to get the rifle. I wanted to shoot in a local praire dog match and the 1-8 I have on my LMT MWS doesn't really cut it out to 450y on targets that small, so I wanted to transfer the Premier to the LMT. I had it on there before in a Larue mount, so I was just going to swap mounts. I started looking and it seemed like I could get the scope in the current AI mount on the rifle- I did have to take off the MBUS- not enough room. To my surprise, even with the cant and the 50mm bell, it would mount up. It also seems that I can get good head placement.

I went out today and shot it. I had to put the PRS stock cheek all the way down, but it fit like a glove. With the Larue mount, I always felt like the scope was a bit high, and I would have some up-cheek on the PRS. Even though I'm thick, my cheek structure does seem to favor a lower weld- so maybe it won't work for everyone, but it works for me. Didn't take more than 2 mils up and over to zero either. Is a winner for me!

Here's a link to the mount. I'll see if I can get some pics of the scope on the rifle this weekend. It looks low, but it works!

I'm just glad the MOA canted rail works with my MIL scope... :p

http://store.accuracyinternationalsrt.com/products/34mm-Picatinny-Mount-(28-MOA).html

Noodles
04-01-13, 23:33
:UPDATE:

So I back came back to this recently and thought I would bring thread back from the dead to bring up what I've found.

YES, you could use the same scope from your AR to your bolt gun. With some exceptions. The AR needs a height of 1.5" above the rail, bolt guns usually need as low as possible, or to preference.

Using this and this,
http://www.laruetactical.com/larue-tactical-ultra-low-mount-rings-qd
http://www.laruetactical.com/larue-tactical-picatinny-riser-qd-lt-101

You could have a .875 ring set, and a cantilevered riser to get you to hieght and extension on the AR. So, the riser stays on the AR and the scope should be free to swap over to the bolt guns (in my case, a Ruger Scout, and a 700). However...

Because the ring height is .875" and that's all your using on your (assuming all your bolt guns have one piece rails) you have a limitation of .875"*25.4 to get this to mm, so that's a max objective diameter of 44mm IF you have a very long rail, so something like this:
http://img.photobucket.com/albums/v221/tokarev/Ruger%20Scout/P1010593.jpg
You're going to be limited in the objective size, most likely going to be crashing into something somewhere.

So.... For most cases or most larger scopes you would need a taller than .875 ring set, BUT you would be very hard pressed to find a riser smaller than LaRue's .625". So, your AR height is going to get too tall too quickly. Not great.


To do this, you would pretty much need to balance the compromise of scope objective, desired and acceptable rail height on the bolt guns, the right riser and parts for the AR, and hope you can get something that will work. I've decided this is not at all worth the trouble!

I've decided that I'll need an AR ring set, and even on a monolithic I might as well get the cantilevered one because my other AR is not monolithic.

I've also looked around and this
http://www.americandefensemanufacturing.com/view/product/322/
Is about the shortest one-piece QD set on the market. This is what I feel will swap over best on my bolt guns. In a pinch, it could be used on some ARs again, depending on setup. I'm going to pick up one of these asap for at least my Scout, but then I'm back to square one with having to shell out for multiple optics which, it doesn't seem there is a way around even if you didn't mind spending time re-sighting them in :) It took me awhile to see there is no free lunch. Also that the AR was absolutely not at all designed for optics!