Fitting a Loose Kydex Grip to a CA-94

For Christmas 2011, I received a Solar Tactical grip wrap for my Coharie Arms CA-94 MP5 clone. Unfortunately, the CA-94's pistol grip geometry is apparently a little bit different from what the Solar Tactical grip was designed for. The end result was that there was about a half-inch of play in the grip - you could pull the Kydex fin down but not entirely off of the grip, no matter how tightly one cinched down the screws.

Why do this to a rifle?

In California, the reason it may be desirable to attach kydex fins or other goofy items to otherwise perfectly comfortable rifles, is that it enables us to use detachable magazines. California law requires that all semi-automatic centerfire rifles must have magazine locks installed (aka "bullet buttons") if they have a pistol grip, flash hider, collapsible stock, folding stock, or forward pistol grip. The kydex fin is used to neutralize the pistol grip as far as CA law is concerned. Once the kydex grip is installed, it's no longer possible to maintain a pistol-style grasp on the weapon. Because that was the only prohibited feature on my CA-94 (and the overall length is over 30"), I may now restore a normal magazine release onto the weapon and then use my lawfully owned 30rd MP5 magazines.

Inventory

3M Durapore medical tape - its description says "A "silk-like" tape with a latex-free, hypoallergenic adhesive that offers high strength and adhesion. It adheres well to dry skin." The nice thing about this tape is that it adheres to itself very well, but not so well to other things. This is perfect if your intent is just to widen the surface you intend to adhere the tape to.
Kydex grip wrap from http://solartactical.com/. This technique is relatively universal though, and would apply pretty much any time one had the same problem.

How It's Done

As always in Gunwiki articles, please be aware that if you want to zoom in on any of the pictures, just click them.

This picture is everything I used in this article, minus a screwdriver. The Solar Tactical kydex fin and the three screws and nuts all came in one package.
A close-up on the grip, and the tape. Note that the grip is relatively straight, but there's a ridge down at the base. This is important, as it guarantees that the tape doesn't have a chance to slide off.
I started wrapping the tape here at the very bottom.
With my initial try, I actually thought that just this amount of wrapping would take care of the issue with the play. Unfortunately, that was not the case.
It turns out that this is how much tape was necessary. I wound the tape around from bottom to top and then top to bottom, then added a couple of extra loops down below. What I was shooting for was ensuring that there was a taper to the grip, so that the kydex would be pushed up as I tightened down the screws.
Another angle of the tape, as well as some gratuitous 3M product placement.
The grip, with the tape installed. It's been tightened down, and is absolutely firm now (vs sliding freely up and down a half inch or so as originally installed).
Another angle. Yes, the bottom of the tape is visible - but a marker would take care of that.

-- SeanNewton - 01 Jan 2012

Topic revision: r2 - 01 Jan 2012 - SeanNewton

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