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How to modify your SCAR grip tang & fit MIAD backstrap

61K views 62 replies 30 participants last post by  PsYkHoTiK  
#1 · (Edited)
I for one do not care for the A2 grip. It's doable, but not something desired. Better grips are out there. I like the Magpul MIAD and MOE.

The FN Scar lower was molded incorrectly with an oversized grip tang. You could not simply remove the A2 grip and replace it with an after market one unless the grip tang cavity on the grip was oversized.

I called Bob (FN) and Jeff (Tangodown) and they said the same thing. Modify the grip or the tang. With the release of the black Scar, I had hoped that FN "corrected this", but no joy.

Two options....mod the grip or mod the tang? Modding the grip will weaken the grip (less cross sectional material left over when done) and you can't use another grip down the road. Mod the grip tang and you can attach almost any grip provided it didn't have a backstrap. So you could use a Hogue. Downside.....if you FUBAR the tang.....your fXXked.

So, here we go......(it is your resposibility if you FUBAR this up. I take no liabilty for YOUR mod.)

BE SURE ALL WEAPONS ARE UNLOADED!! :?

I presume that anyone that has a Scar, already has a M4 and clones. If so, this will go much quicker.

Here's my Colt 6920 (that I know is in spec). Remove pistol grip.
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Take a piece of paper so that you can use the corner to overlay against the grip tang. Crease along the three edges of the grip tang. Cut along the creases and corner. This will give you a rough template of the in spec grip tang. Trim the template to fit better on the M4 grip tang.
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Here's the template.
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Tools that make the job easier: safety glasses, dremel, medium grinding wheel, fine polishing wheel, flat file, pencil or marker.
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Again, be sure your weapons are unloaded!!
Remove grip from Scar. Use your new template and overlay it on the Scar grip tang. As you see, there is too much material on the diagonal edge. Approx. 1/8". (I already started grinding, so there's not much left against the template) Once that is removed, the other edges come into close to spec with the template. Use a pencil to mark the excess limit to remove.
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WEAR SAFETY GLASSES!! You'll get hot shards of plastic in your face depending on the rotation of the Dremel wheel.

GO SLOW if you use a Dremel and leave plenty of room to hand file for the final fit of the edges. Use the flat file to make sure the grip tang is flushed!
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Check for grip fit every so often.
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Personally, I like to choke up on the grip and the B1 backstrap is no better than the A2 grip to begin with. I wished someone else had posted a "How to do for dummies", since I wasted a MOE during the "learning process." :-(
This is the B3 backstrap I used as the "second" try. You can see the interior profile needed from the rear view.
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Here's the B2 backstrap on the left with the needed profile and the MOE on the right with a much shallower profile.
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Here's the top view of the needed contours of a B2 backstrap.
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BE CAREFUL GRINDING AWAY NEAR THE EDGES. I got too close on the MOE and B3 backstrap and caused a flat edge on the upper right curve as seen below. (MOE on right, B3 in the middle, B2 on the left).
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Go slow and try fitment.
Finished end results.
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The MOE was my first attempt. The B3 was the second and I got the profile needed down pat. The B2 was the final attempt. I did it in a minute. Remember to stay away from the edges or grind there too long. You don't want a flat when it should be a curve.

I used the original Scar grip screw and checked for clearence with the trigger components. Cleared fine. IF YOU REMOVE TOO MUCH MATERIAL FROM THE DIAGONAL FLAT OF THE SCAR GRIP TANG, THE FACTORY SCREW MIGHT CONTACT THE TRIGGER LOWER FLAT. IN THAT CASE, A CUTTING DISK IS HANDY.

And no I did not do this in my living room. A good vacuum can hide evidence. :D

Hope this helps someone out! :?

 
#4 ·
Nice job indeed.

Do you have a Hogue grip to put on and take photos?

Curious how that would look and fit with the receiver at the back strap area.
 
#5 ·
SONYtec said:
Nice job indeed.

Do you have a Hogue grip to put on and take photos?

Curious how that would look and fit with the receiver at the back strap area.
Unfortunately I do not. I long ago sold my Hogues when the MIADs came out. The Hogue would fit like the A2 along the backstrap of the SCAR. Without one, I can't say for certain.

FYI-there is a company that makes a hogged out Tan Hogue grip that fits the existing oversized Scar grip tang. It goes for $50 IIRC.
 
#32 ·
Unfortunately I do not. I long ago sold my Hogues when the MIADs came out. The Hogue would fit like the A2 along the backstrap of the SCAR. Without one, I can't say for certain.

FYI-there is a company that makes a hogged out Tan Hogue grip that fits the existing oversized Scar grip tang. It goes for $50 IIRC.
Desert Dog has them for $39. Ouch, thats twice the price as a standard Hogue but I think I'll take that option rather than go whittling on my grip tang.
Hi-desertdog Scar Grips - hi-desertdog.com - (Powered by CubeCart)
 
#6 ·
OK, thanks!!
 
#9 ·
steve1968ls2 said:
jmoney911 said:
+1 :shock: nice write up sir. might give it a try if I get up the courage to cut on the SCAR...
You don't have to "cut on the SCAR"... just on the MAID grip.. :)
Great! Another way to skin a cat.

Steve, can you snap some photos of your modified MIAD in the grip tang/backstrap area? It would be nice to see a comparison.

Thanks
 
#10 ·
Perhaps they did change the tang on the later SCAR's, I didn't have to modify anything on mine, just the dovetail backstrap on the MIAD, to get it to fit. Everything else seated properly, but mine is a later black poduction run.
 
#11 ·
bm11 said:
Perhaps they did change the tang on the later SCAR's, I didn't have to modify anything on mine, just the dovetail backstrap on the MIAD, to get it to fit. Everything else seated properly, but mine is a later black poduction run.
Do you know the serial number? On mine, when I try to get the MIAD w/ b1 backstrap to be flush with the trigger guard, it drops down 1/8" from the lower ledge of the Scar frame. Is you frame tan or brown?

There is a photo of this over on ar15.com in the armory section under fn.
 
#12 ·
DOE said:
bm11 said:
Perhaps they did change the tang on the later SCAR's, I didn't have to modify anything on mine, just the dovetail backstrap on the MIAD, to get it to fit. Everything else seated properly, but mine is a later black poduction run.
Do you know the serial number? On mine, when I try to get the MIAD w/ b1 backstrap to be flush with the trigger guard, it drops down 1/8" from the lower ledge of the Scar frame. Is you frame tan or brown?

There is a photo of this over on ar15.com in the armory section under fn.
As he said, it's black. :?
 
#15 ·
bm11 said:
Yes, black frame. I didn't run into any issues with the grip itself, only the dovetail backstrap, which I sanded to match the contour of the reciever.
That's great! :shock:
I for one complained when I couldn't put my favorite (insert brand) grip on there. Good thing FN listens to suggestions from owners. It's actually saving them money on plastic in the long run.
 
#18 ·
Nice, DOE.
 
#19 ·
i refuse i take any files or a dremel to the lower on my scar so to get my miad onto my scar i only modified the grip and it still fit decent. I had to modify the backstrap and the depth of the inside of the grip but it works fine. Ill post pictures up when I get a chance, but I think I'll do the backdrop back strap again with the b3 because I accidently made the sides a little flatter, the contour sits not need to be changed just the inside area.
 
#21 ·
As a side note......if you remove too much material from the grip tang, you can shim back the "removed" depth with metal washer(s). Place them between the grip tang and grip and tighten down the screw. :?
 
#22 ·
MOUNT-N-SLOT said:
devilmoon said:
i refuse i take any files or a dremel to the lower on my scar so to get my miad onto my scar i only modified the grip and it still fit decent. I had to modify the backstrap and the depth of the inside of the grip but it works fine. Ill post pictures up when I get a chance, but I think I'll do the backdrop back strap again with the b3 because I accidently made the sides a little flatter, the contour sits not need to be changed just the inside area.
I agre with you!

IWC Team milled 0.100" from the flat inside a MOE HG and then used a Dremel with a Sanding Wheel to shape the tang. Now the MOE grip fits perfectly.

I'll post a pic in a few days.

MOUNT-N-SLOT
Pictures Please! :p
 
#23 ·
So.... I wanted a better grip (mostly because I love having the storage) but I was unwilling to cut on a $2400 rifle. However, cutting on a grip is no problem. I figured that even if I butcher it a bit who cares. Below are some pics of how I modified the inside of an MOE grip using a dremmel with one of their high speed cutters.

In the first pic you can see the high speed cutter as it would be placed while cutting. I took a little at a time off until it fit. Note that since the cutting bit is round you will have to cut a little in front and behind the slant to make sure it is properly hollowed out. None of this is visible when mounted.

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Here is a pic of all the grinding work I did. Note that this was my first attempt. I am happy with it but its not perfect. I ground a little to much on the back strap portion at places.

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Here is a pic of it mounted. Fits nice and snug though you can see where I took to much off the back strap.

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#26 ·
I too originally didn't want to "mod" the lower and went the "grip mod" route. It fit just like yours. For me, the grip interface area was just not thick enough for my liking. I didn't want to be in the field and have to one hand my rifle with all the other stuff (i.e. light, bipod, etc.) on and have it snap off at the grip screw area. Knowing my luck, it would happen.

I'm glad it works for you. Thanks for posting pics. This will give folks some great ideas on what to do and what is needed. :?