Telescope Mounted Green Laser Sight

Rod Nabholz



Green Lasers - A great tool

For any astronomer who ever tried to point out an object in the night sky before the wide spread availability of green lasers, the idea of going back to those times seems like a very bad idea. 

"No, not that one, that sort of bright one next to the kinda of dim one, diagonal from the really dim one...." 

Not particularly productive, and frustrating for all involved.

That all changed with green lasers, now we just draw our Jedi light saber and point to the intended object with, well, uh, laser accuracy, and are often greeted with few oohs and aahs... I never get tired of that.

It wasn't long until that utility found its way to our scopes as well.  The laser mounted on a scope is a great way to understand precisely where your scope is pointed, and makes starhopping a pleasure. 

Commercially available mounts are out there, and are generally priced from $50 to $100, depending on whether they include the laser or you have to provide your own.

While I loved my hand held laser, when it came to mounting one on my scope, there always seemed to be something else in this hobby that demanded the 50 to 100 clams more. But things changed recently when I came across an interesting Ebay listing.

Ready, Aim, Find...

That Ebay listing was for a green laser that was built for a firearm. (Search for "green laser sight" and you will be presented with lots of options.  Amazon carries them as well.) The laser mounts to a rail on the gun, and is actuated by a pressure switch mounted on the hand grip.  The listing showed the laser, a mounting sleeve, interchangeable switches, (the momentary pressure switch and a simple on/off version). Also included, was a mount designed to be mounted to a gun barrel,  an allen wrench for the mount and sight adjustment turrets, and even a CR123 battery to power the unit. 

It occurred to me that this would be perfect for mounting on a telescope

And the best part, just $29 shipped.  I want one!

Mount up!

With all that was included, there was one thing still missing for mounting it on a scope.  The laser was designed to be mounted to a gun that had a mounting rail for such accessories. As my scope obviously does not have such a rail, I needed to add one.

Fortunately these rails are commonly available.  In this case another Ebay search and $10 shipped got me what I needed.  It is a product made by a company called UTG, and is known as a "Ruger 10/22 to Picatinny Tactical Rail Adapter" part number MNT-22TOWL. ( Search Ebay or Amazon) It is a simple piece of aluminum machined to a standard pattern common in firearms circles for mounting accessories (known as "Picatinny") .

I simply mounted this rail to my scope, taking care to align it as carefully as possible with the axis of the tube.  I used a square laid across the end of the tube as a reference.  Two small holes drilled in the tube, two #6 cap screws, washers and lock nuts and it was firmly mounted in place.  You could also mount the rail with some good double sided tape, but get the good industrial stuff, as the laser does have some heft to it.

Switch Me On

For my purposes, I decided I liked the utility of the momentary pressure switch.  It seemed the momentary switch mounted in the right spot it would be easier to deal with than accessing the on/off switch on the rear of the sight.  I decided to try the switch placed at the top of the tube, in a spot that my hand would fall on naturally when adjusting the aim of the scope.  I simply held it in place for the trial with a strip of duct tape. Once I settle on a final location, I will attach it with double sided tape.

Getting on Target

Like any good sight, this one has adjustments for fine tuning your aim.  Under the caps on the sides of the sight are adjustment turrets that are turned using a provided allen wrench.  I was originally concerned with the available adjustment range, but with careful mounting of the rail, there proved to be no issue, there was plenty of adjustability.

Fine tuning the aim of the laser provided me a glimpse of how much I was going to enjoy using this laser.  In daylight I picked a target about 100 yards away that was slightly shaded.  Centered the scope's view on the target, and turned on the laser.  It was close!   Using the allen wrench, I turned each turret, each making very positive clicks at each increment until I dialed it right in.  It could not have been easier.

Like Shooting Pisces in a Barrel

Under the skies, this sight is a real pleasure to use.  Seated on my observing stool, I simply reach up, grab the scope, actuating the laser's switch and immediately the bright beam shoots upward.  I can instantly place the scope on the intended target or position.  If you have ever contorted your body while trying to position yourself in line with a optical finder scope or Telrad, you will certainly appreciate how finding your way without all the gymnastics could be a joy. 

The beam is bright, the switch is convenient and easy to access.   Using the momentary switch means the laser is on only as long as necessary to find the target and then extinguished, saving battery power. The mount is very solid and I would expect a sight and mount designed for firearms will have no problem serving the relatively tranquil pursuit for which I have recruited it.  I don't know how long the battery will last, but I expect it will go for a good while, but throwing an extra CR123 battery in your eyepiece case is probably good insurance.


In two outings this sight has proven to be an invaluable enhancement and improvement to the accuracy and enjoyment of my observing. At a cost of a mere $40, there are not many accessories that will provide such great value at such a low price. 

Highly recommended!!

I welcome your comments and questions at

 2014   Rod Nabholz

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