Gunsmithing MST-100 Mount Question

[ArcticLight]

I'm waiting on an MST-100 and base unit...

Now, when I had my smith build my rifle he mountd the USO base on my Rem 700 - drilled and tapped for the larger screws...
I gotta give him a call, they are not 6x48, but are 8x??? Wanna say 40...

I'm hoping this will not be a problem, although I would open up the base for hte larger screws if need be..

After reading the M40A1 build guide looks like everything is in the right place..

 

[ArcticLight]

Re: MST-100 Mount Question

FYI here's a pic of my rifle, damn I gotta clean the base bedding off ..

 

[Switchblade]

Re: MST-100 Mount Question

Scott, call Geoorge at GAP. He has built many of these and can answer your questions with a knowledgable voice on the other end of the phone line

 

[chad3]

Re: MST-100 Mount Question

They are the smaller 6x48 standard screws. Have the mount and fit my clip slot action fine with no changes.
Looks like you may have to open up the mount.
Chad

 

[mcm308]

Re: MST-100 Mount Question

If your talking about the USO replica of the Unertl mount with the soldered inverted screw rings for the M40A1/MST-100... That base is made for the factory 6-48 size screws. If your receiver was drilled and tapped for 8-40 screws... That will create a problem. If that's the case, you would have to give GAP a call and see if they can machine the holes in the base to accept the larger screws.
Hope this helps..

 

[sobrbiker883]

Re: MST-100 Mount Question

Thinking the USO base would need to ride in a clipslot receiver wouldn't it?

 

[7mmRM]

Re: MST-100 Mount Question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body">Thinking the USO base would need to ride in a clipslot receiver wouldn't it? </div></div>

They made a slotted and non slotted base.

 

[ArcticLight]

Re: MST-100 Mount Question

I can get the rifle clip slotted well enough, but realistically, why....added expense and I don't shoot highpower with it so there's no reason to reload fast, assuming the scope was damaged and I was in combat with iron sights...far fetched...

It's not an exact M40a1 clone either but if the base requires it - no prob, if not then no prob either!

 

[mcm308]

Re: MST-100 Mount Question

The reason for the clip slot was to load the stripper clips. However, When the factory clip slot actions had scopes installed..I think the 1st ones were the M40's It's original purpose became null because you can't load the clips through the scope.. So, someone... I think John Unertl decided to use the clip slot cutouts for extra strength on the scope mount... The only rifles that use clip slot receivers with scopes are the M40A1's and A3's...that I know of...

 

[mcm308]

Re: MST-100 Mount Question

And if you don't want an exact clone... skip the clip slotting ,Install a rail with 8-40 screws...get some 1" rings and be done with it.

If you got a Clip slotted base.. Just sell it on here.. It'll go like a hot cake !

 

[sobrbiker883]

Re: MST-100 Mount Question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 7mmRM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body">Thinking the USO base would need to ride in a clipslot receiver wouldn't it? </div></div>

They made a <span style="font-weight: bold">slotted and non slotted base</span>. </div></div>

That should do it......

 

[ArcticLight]

Re: MST-100 Mount Question

Talked to my smith, he said he'd clip slot it, he's gonna be whacking off 2" off my barrel and re-crowning it anyway....

See if I get the base first! Otherwise a base/1" rings it is..

 

[abnrgr]

Re: MST-100 Mount Question

What is the difference between the Unertl 10X MST-100 scope for the M40A1 and the MST-150 for the Barrett .50 cal M82A1A?
I read somewhere that there are ~ 81 transferable MST-100's out there and ~ 31 MST-150's.

 

[wilshire1412]

Re: MST-100 Mount Question

I think the main difference is going to be in the elevation adjustments between the two scopes. The MST-100 is set up with the come ups built into the elevation for M118 7.62 ammo, I have only seen the .50 cal scope in photos but it did appear to have a different set of graduation marks for distance/elevation.

 

[BasraBoy]

Re: MST-100 Mount Question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: The Bad LT</div><div class="ubbcode-body">What is the difference between the Unertl 10X MST-100 scope for the M40A1 and the MST-150 for the Barrett .50 cal M82A1A?
I read somewhere that there are ~ 81 transferable MST-100's out there and ~ 31 MST-150's. </div></div>

Check out this link to USO....gives a little overview of the 100 and 150:

http://www.usoptics.com/product.php?partnumber=MST-100

This link (go to p15) gives the NSN numbers etc if you want to dig a little deeper:

http://www.lejeune.usmc.mil/lmt/download...May%202006_.pdf

 

[abnrgr]

Re: MST-100 Mount Question

I read that the MST-100 can have its BDC 'compensator wheels' , whatever they are, "changed at the factory [meaning Unertl-good luck finding that factory ] to match the .50 M33 trajectory" thus resulting in the MST-150. Does anyone know of a place that could do such work? I've got an original " 10X Sniper " marked Unertl that came from the FBI and I'd like it to be proper for my M82A1A from Desert Storm. Also, anybody know what scope mounts were used to install these in 1990/1991?

 

[LoneWolfUSMC]

Re: MST-100 Mount Question

IIRC they were badger rings and they were mounted directly to a high rail that came welded to the M82A1A from Barrett.

As to who did the BDC conversion, I have no idea. It worked pretty well.

 

[abnrgr]

Re: MST-100 Mount Question

Wolf-I'm new to this forum business. Please advise what "11RC" refers to, at the beginning of your reply.
You have been a great help. It appears that nobody knows jack about this. Luckily I was able to procure the Badger MAX 50 ulra-high rings at 1.425" height -necessary due to the bulbous nature of the Unertl 10X Sniper Scope. I was afraid that the rig would be too high considering the raised scope rail as you mentioned. However, with the cheek rest it gives an outstanding field of view, if that's the term. Semper Fi, Bro.

 

[LoneWolfUSMC]

Re: MST-100 Mount Question

IIRC = If I Remember Correctly

 

[long-shot]

Re: MST-100 Mount Question

Artic,

You may want to just use a standard Pic rail and 1" rings. The eye relief with the total A1 setup isn't quite right, and there's almost not movement back and forth to make it right. I can still shoot it reasonably well, but just food for thought.

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1074474#Post1074474