Non tactical M4 scope mount issues

[Gutpile Charlie]

I've just completed another AR build, an "old school" M4 with standard fixed base front sight and a detachable handle/rear sight:

http://i106.photobucket.com/albums/m275/gutpilecharlie/M4Table.jpg

I would like to mount a "non tactical" scope, say a Leupold/Burris/Weaver 2x7 or 3x9 on the receiver's rail.

My question is, how high does the scope have to be mounted so as the front sight does not become an "issue?" What kind of mounts would you use, how high should the center line of the scope be above the rail?

Next, do Weaver mounts work with the Picatiny rail? Will the Weaver claw mount fit and function....is it compatible?

I'm not trying to build a tactical carbine, just want to periodically take off the handle and put on a scope. There is a very wide range of prices for scope mounts, and I don't really plan on using $150.00 mounts to mount a $250.00 scope. What is a good compromise?

What rings would you recommend for this?

[SkiDevil]

Hello Charlie,
I am not an optics expert, but I will chime in for you. I think what you want to do is possible, but may not be the most optimal set-up. -Once you explore a few of the options, you will know what works for you.

The reason I state this is because I tried the cheapest route I could find which was quick detach rings and a 3/4" riser. It was not very secure in my opinion and resulted in way to many screws/ fastners for my comfort. The cost can be as little as $50 with a medium priced set of rings.

The other option is to purchase a set of Ultra-High or AR15 scope rings to forgo the riser (Warne and Leupold produce these). I have shot an AR with this type of set-up but never owned/ bought it myself. However, it seemed better in my opinion than the riser and scope rings. -These type of rings cost around $70.00 to $90.00.

Third, option and probably best low-cost option would be to buy a economy one piece mount like the new Burris pepr, Wilson's on-piece mount, or an equivalent such as the Armalite model. -These mounts will run from around $70.00 to just over $100.00

Depending on much you decide to use the optic, one of those options may work for you.

Personally, I would save-up or watch the EE Boards on this forum and others for a good deal on a used one piece mount such as an American Defense Manufacturing (ADM) model or La Rue. I have seen quite a few of the 1" ADM models for sale lately.

Below are a few threads for you to check-out. They are not completely on-point but may be of use to you. Skim over some of the recent threads in the optics forum or try the search function, there may be other threads that are useful for your query.

Good luck in your search,:D

SkiDevil

Links:
https://www.m4carbine.net/showthread.php?t=55391

https://www.m4carbine.net/showthread.php?t=34646

https://www.m4carbine.net/showthread.php?t=29046

[huudoo]

this will work fine for a regular scope.

http://www.johnmasen.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=J&Product_Code=1520N&Category_Code=XTSM

[JSantoro]

My question is, how high does the scope have to be mounted so as the front sight does not become an "issue?"

With a magnified optic, it generally isn't an issue except for those that Jedi mind-trick themselves into thinking it is.

The FSB is close enough to the optic that, even with fairly low-mag optics like a 1.5x, it is a blurry smear at the 6 o'clock portion of your field of view, and one that is functionally transparent. The optic can't focus on the FSB, and "burns through" it, in the same way you can see through brush with a set of binos if you're right up on said brush, yet still see clearly whatever it is in the distance you've focused on with said binos.

Primary example that pops up here all the time is with ACOGs. For example, a TA31 on the stock TA51 mount and mounted to the receiver has a height-over-bore of 2.755", and is a 4x32 optic. Fixed FSBs do not impede the usability of the scope unless you vapor-lock on the blur at the bottom instead of what you're supposed to be shooting.

Regardless, that can be enough of a mental hangnail for some folks that they are forced to choose between sucking it up, getting taller mounts, or ditching the fixed FSB. Which is fine, of course; everybody has their favored setup and should go with it if they have the means, but the blurry FSB is a mental issue, and the ones that find this troublesome are a distinct minority.

Somebody did a thread about this, having taken pictures of FSBs through various magnifications. I tried and failed to dig it up via search immediately prior to this, but it's floating around and could give you some visual cues that would allow you to decide for yourself, if somebody better at rooting around in the archives than I am can find it.

[Rosco Benson]

The major problem with mounting a scope on the AR is getting it far enough forward for proper eye relief. This is particularly true if you run your stock shorter than fully extended.

The LaRue and similar mounts canteliever the scope farther forward. If you're looking for a cheaper alternative, the Burris PEPR mount looks like it might be a pretty good one.

Bottom line, just trying to run tallish rings directed attached to the flat-top isn't going to work.

Rosco