Huben Huben GK1 .22: A Beginner's Journey to a DIY Mini Carbine

No I agree, that is a very fair price. I love the robust after market for this pistol. On the other hand, certainly one must notice that I have made my own unit. Cost me about 1 hour in design and prototype time, maybe a dime in materials, $10 in screws. Also, I am making my stock from a broken hiking stick.

Converting a Ski Pole to a Stock!






I knew I was going to cut the sticks at the portion where it would be a uniform diameter, altho the black and white portions obviously have different diameters.

I designed the mounting block in several pieces.

The first was a piece to attach to the pole:


The side blocks would be threaded to 6-32 for set screws to lock to the pole.




This interface bracket would then mount to a bracket that would clamp to a picatinny rail:








The picatinny clamp portion:


I designed the block to exactly reciprocate the shape of the picatinny tower (red outline).

2x6-32 screws would pass through the smaller clamp block into the body of the main block, which would be threaded (Yellow arrows).

The little green block sits exactly between 2 slots of the picatinny rail to prevent the block from sliding up and down the pic rail.




So, off they went to the printer.
I bonded to pole mount to the clamping block with Tap Plastics Acrylic cement--literally melts the plastic into 1 solid piece.






Mounted up with the pole:

Hi all! Back after some traveling.

DIY Ski Pole Stock, Mark 1

Next I designed the shoulder interface portion:

This was actually the most complex thing I had designed thus far.



I went for a J shape, which is channeled to accept some rubber gasket I had laying around the shop. Then there is the tube interface portion with the set screw mounts. And finally the wing between the pole interface and the J in order to stabilize the J.




Off the printer:






Added the gasketing, stuck it on there with some hot glue:








Cut the poles to the appropriate length:











Added a little heatshrink to cover up the white portion of the pole, and I give you my adjustable length pic mount stock made from a ski pole:

DIY Stock from a ski pole, Mark 2

My first version as pictured above had just a tiny bit of wiggle at the pic rail attachment.

So I revisited the clamping method.

After examining various off-the-shelf clamps of all sorts, I realized that my approach was wrong. The point of the clamping portion is NOT to reciprocate the shape of the picatinny rail tower. The point is to use the shape of the picatinny tower to clamp to, in order to stabilize the attached device. A subtle but important difference.

So here was my redesign:



Stability is all about the clamping surface, highlighted in red. You need to generate strong force in the direction of the arrows, so that you clamp hard against the reciprocal face on the pic rail. Since the interface is slanted, this force will both hold the clamp centered as well as pull it tight to the pic rail.

For this reason, I went with a 3 piece design. I felt the symmetrical clamps would give more stability.

To generate more clamping power than a reciprocal shape could make, what I did was slightly bevel the center block portion (blue highlights) until they are actually slightly smaller than the reciprocal face on the pic rail. The difference is only about 0.4mm--too much difference and you will crack the clamping blocks. Too little difference and you will get less clamping power.

Next, I moved the through-screws much lower down, so that they are clamping as closely to the red surface as possible. They are low enough that you have to position them to go in between the pic towers. See the yellow circles.

The green highlighted stub remains, also lying in between the pic towers, which prevents the clamp from translating up or down the pic rail.



Here is the set, off the 3d printer.






And mounted up. Now this was fully stable, with no wiggle, even when exerting strong torque at the far side of the stock.