The last thread got archived- here is some further information-
the Tri-wing screwdriver from ALI express (From China? Took four weeks to get here) noted in the original thread is the smaller one- won't fit the screw in the gun. BladeHQ has Mictotech tri-wing screwdrivers- medium size, that will fit. Downside is that it was $22 dollars. @MadDogDan

The reinforced mag catch from Promoted Pawn came in.
Have any members taken out the catch,  would you mind describing the process?  @Manticore_Arms
Also, is there a separate spring that needs to be swapped out? Or is a leaf spring or something?
Thanks and Merry Christmas!

@PiGood

What does the tri-wing screw look like? Please Post a photo. If it’s what I think it is it is what we use on aircraft. Particularly what was used on the Lockheed L-1011 Tristar.

I no longer have my MSAR, but I can tell you it's tri-pin, not wing.  

Tri-Pin (makes more sense- but on the site they call it medium domed  Tri-wing tool bit) from BladeHQ, medium size.  I saw someone else's post of the screwdriver with a T-handle attached, the ones I are just the bits.

My post sort of reads like a smartass; I didn't intend that.  I was searching "tri-wing" for the correct MSAR images, and they were all just different variations on basically a 3-legged phillips.

I do see the MSAR tip being labeled as Tri Wing, but I wanted to be sure everyone knows that it's in fact a correctly sized bit with 3 pins they want to look for.

You should be able to get either the tri-wing or 3 dots from “apex”. They make all types of screwdriver bits. I forget the technical name for the 3 dots. I think it’s called a three pin or tri-pin Spanner. It’s a security type bit so that things can’t easily be taken apart. We used them to install the armored cockpit doors after 9/11.

Sorry haven't been over here for a while.

It is pretty strait forward, although a little bit of a pain.
Personally I remove the trigger pack, and barrel/receiver. It is not necessary, but it makes it easier to manipulate the stock.

Loosen the tri wing screw until it is free.  
There is a decent Coil spring under the magazine release your just applying enough counter pressure to allow you to pull out the screw.

The magazine release shouldn't pop out yet. There is a retaining flat on the end of the magazine release closest to the trigger pack.
You will need to lightly press the release upward into the stock and slide it forward towards the muzzle just enough to clear that latch. It is only a 1/4-1/2in forward, don't go any farther or you risk smashing the coil spring. Once your past the ridge you can release the spring pressure. Almost out, you will need to depress the Magazine latch in the magazine well and wiggle the release a bit and at this point it should come out the bottom of the stock with out too much issue. Be warned when this comes free both the coil spring under the magazine release and the spring under the magazine latch like to go flying, unfortunately both of your hands are full at this point so I haven't really found a good way to keep it from happening.

Now your down to the latch, pivot it out 90 degrees so it will be perpendicular to with the magazine well. Pry or pull it towards the opposing wall of the magazine well and it should fairly easily pop out of the split circle guides that hold it.

Putting it back together is just doing it in reverse and saying bad words when the springs go flying.

As far as I know the bits were proprietary. I gave up trying to find the correct bit and ended up making my own, it nothing amazing but it dose the job.



It was just a piece of 1/4in hex crs and 3 1.2mm hss drill bits. I think I had about $10 and an hour in it.
Mind you that was a 10 pack of China Drills for $4.50ish and the rest was a 3ft drop of 1/4 in hex steel.

So here is my drawing and my process, it might help some one.
Gun is in Metric, so the print is in metric.



I just cut about a 1 in piece of hex, length don't really matter, tossed it in the lathe to face off the ends and added the stock clearance. Then over to the mill.
Set zero at the center, and used the china drills to drill the three holes 1/2in deep or so. These were slightly oversize but I didn't have anything the proper size for a press fit, so I lightly peened the holes and filled them with glue, aka red locktite, and pressed in three of the 1.2mm drills shank first.
After that I got fancy and used the cut off in surface grinder with the bit mounted in a rotary head to cut all the pins off at roughly 2mm but you could probably do this with side cutters or a dremel and get the same result.

Edit : Small note, the holes in the screw are actually 1.25mm+ I picked 1.2mm drills due to availability and it gave me some tolerance to work with if I didn't quite get my dimensions perfect. Also I made a 3D print with thru holes that would just need the drills pressed in, but never tested it because I figured I would be taking it in and out enough with developing the custom one for my rifle that I should probably make it out of steel.

Thank you @PiGood, sounds like a huge pain in the ass rubix cube.  I'll play with it and either fix it or fuck it up and take it  Drury's Whalen.