Machining a featureless stock - Opinions?

[TerraHawk]

Hey Guys,

I am making billet machined aluminum featureless stocks for myself and a few of my friends and I thought I would ask for opinions on the design. I saw one that was plastic and although it is probably fine, the engineer in me shudders at repetitive impact force on plastic. Especially since it is held on with a single 1/4-28 cap screw. Since I am starting with a block of material, adding features just adds a little weight.

It is pretty easy to change the overall length based on the distances I measure from my wife's and friend's preferred position on their adjustable stocks.

The shoulder piece is machined delrin with a sorbothane insert for shock.

So, any suggestions? Thanks in advance.

Todd

[Marauder2003]

I think as soon as you connect the buffer tube to the stock you have created a thumbhole stock. Even if you can put your whole hand in the hole.

[jeffyhog]

Agreed, I think that would be considered a thumbhole stock.

[MechaDad]

But a very innovative thumbhole

[AreWeFree]

Very cool, but not featureless and completely impractical.

[Exile Machine]

Not qualified to be offering legal opinion, but that particular topology is what is known in the field of higher mathematics as a "thumbhole stock."

Regarding the impact force on plastic causing you to cringe, polymer gunstocks are typically made from glass filled nylon. That's one of the strongest engineered materials available, and more than strong enough to handle the force of recoil, especially when you consider that the force of recoil is countered by the the shooter's shoulder. There is no part of the human shoulder which is strong enough to bust a thick chunk of glass filled nylon.

[SkyHawk]

Thumbhole. And plenty of Military issue M4s hold up just fine with 'plastic' stocks.

[sloppy joe]

Looks like a thumbhole stock to me.

[Ryridesmotox]

Suggestion,

The whole portion that connects to the buffer at the end can go away. the Aluminum will be strong enough with just the bottom structure (grip to pad) without needing to attach to the buffer... Also, that looks like a pretty long length of pull, even for me. What buffer length are you thinking? Because an A2 rifle buffer tube with that much space behind it would need some long arms to be comfortable

[luckyduck]

Would be helpful to get a legal opinion. From what I've understood is that the thumbhole stock is also held to the pistol grip definition in terms of positioning of the hand.

[spoof145]

Just get rid of the part that connects to the buffer tube. AND THEN send me one please, and thank you! It looks nifty. Standard A1 stock length of pull works for me.

[TerraHawk]

Thank you all very much.
"Thumbhole stock" is out.

Length of buffer tube is 7.35" from back of Lower as measured by my buffer tube. Distance to back of stock is 11.31" from back of Lower as measured from my adjustable stock at max extension (where I shoot).

Would a cheek rest attachment be desirable?

Suggestion,

The whole portion that connects to the buffer at the end can go away. the Aluminum will be strong enough with just the bottom structure (grip to pad) without needing to attach to the buffer... Also, that looks like a pretty long length of pull, even for me. What buffer length are you thinking? Because an A2 rifle buffer tube with that much space behind it would need some long arms to be comfortable

[TerraHawk]

Just to clarify, I am not against plastic! All of my collapsible stocks are made of plastic and they are fantastic. The issue is that my plastic stocks are mostly loaded in axial compression with relatively even stress distribution. Attaching the stock off the center of impulse guarantees bending moments. The interface available for attaching the stock is 60 degrees from horizontal and has only a single screw. Over time, I think there is the potential for issues to arise.

[Ryridesmotox]

I was referring to the whole top half of the parallelogram there... You could probably just take that whole portion out.

Or the bottom portion. If you could remove the bottom portion that would probably be even more desirable for a precision competition shooter. That way you could get a good positive hold with a support hand to press the stock into a shoulder. maybe even have a small removable attachment for a monopod or pic rail.

[Ryridesmotox]

Forgive my horrific 'paint' skills

It would also remove half of the weight. Aluminum should be able to handle that no problem