Industrial AR15 hydraulic shock buffer

[N555]

Upper is a 16 inch midlength, in the 1 true AR15 caliber.
*not an original idea* I got the idea from the M4 buffer tube that has a buffer stop screw. I figured why not make it a shock instead of a dumb screw?
I sacrificed one of many no thrills M4 carbine tubes I have laying around, drilled it out to to 10mm installed an industrial hydraulic shock absorber from SMC (made in japan, they make industrial automation stuff). It took up about 3/4 of an inch of the bottom of the M4 tube. So I dropped in a heavy stainless steel body, 2.5 inch long AR10 buffer (2 weights), both weights tungsten. The SS AR10 body buffer with 2 tungsten weighs about 5oz. AR10 carbine buffer is about 3/4 of in inch shorter than the standard M4 carbine buffer.
The buffer starts touching the hydraulic shock just past bolt catch, so it should work.
I can punch the tube hole out and put in a bigger 12mm shock if needed.
Only draw back is the hydraulic shock sticks out the back of the stock and can only lock the magpul ctr M4 stock down in the number 4 position if say fully collapsed is 1 and fully extended is 6.
What do I expect it to do? Hopefully produce very soft pleasant recoil.
Should be able to test today.

 

[N555]

Like butter.
Full auto or 3 round burst would probably be controllable with no training. I found 3 round burst to be useless beyond about shotgun range on carbines as setup by the dot mil.
Note that is the 12mm, next size larger hydraulic shock absorber shown.
Actual AR10 buffer shown.


Installed with stock removed.


Magpul full retracted.


M4 stock retracted, with the shock sticking out about 2mm, one click away from the fully retracted position. Aside from the length of pull being about 4 inches off for me it seems shootable.

 

[NIGHTLORD40K]

Neato!
Of course longevity is an open question in this application, but you would know pretty quickly if the shock blows out, lol!

Heckler and Koch tried something similar with the .380 P7s and they didn't last very long.

 

[N555]

These things do thousands of cycles per day, 7 days a week for several months straight before they wear out.
If the buffer is hitting it too hard, then I'll go up to the 12mm. I put one of these 12mm shocks in a vice before and hit it with a hammer trying to make it blow out, I was unable to.

 

[DukeConnor]

is it quiet ?

 

[N555]

is it quiet ?

For a suppressed AR with full power ammo, it's pretty quiet. No twang sound.

 

[taliv]

i had the original version of the enidine hydraulic buffer back when i had my full auto AR

M4 Recoil Buffers & Devices | Recoil Reduction | ITT Enidine

it was cool but didn't make THAT big a difference for me

 

[FOGeologist]

I really appreciate your sense of innovation here. I would be interested in hearing about what happens after you shoot a thousand rounds. I wonder if this would work through a carbine class?

 

[N555]

If the 10mm shock dont, the 12mm will.
The worn out shocks I have replaced over the years die slowly, getting easier to depress until they offer little to no resistance. They wear out over hundreds of thousands of cycles.

 

[OrangeCat]

Be interesting to see if you could make a buffer weight body and screw the hydraulic buffer into it instead of the tube that way you could just drop the buffer in as is and set the stock as low as you need.

 

[gotboostvr]

Someone already makes a tailor made hydraulic buffer system. Replaces the spring and buffer entirely.

https://www.jprifles.com/1.4.7.2_os.php

It'd be interesting to see this DIY set up ran side by side against the JP system.

 

[N555]

Mine is for po people.
Problem is people barely want to cough up the money for an H3 buffer, which is only like $50 for the whole thing, $30 of you open up the buffer and load it with tungsten weights your self.
I need the buffer to be heavy on mine.

 

[mshootnit]

I see this as being useful in the overgassed AR10s

 

[Zerodefect]

I'd love to see it work against the JP.

And nearly everyone running a LPVO has the stock no closer than #4 usually. So the 3gun crowd setup's should work fine for you. I wouln't want to do this to a 1x reddot carbine or KISS carbine.

 

[Varminterror]

In addition to the JP Silent Captured Springs on the market, Nemo uses a “bouncing BCG” design to reduce the impact of the reciprocating mass against the receiver extension - same idea, but potentially with a greater deadening influence, as the “spring” in your system is catching the reciprocating mass at dead length, and the Nemo design, in theory, allows the buffer to arrest and begin recoil before the BCG has fully arrested. I’m not certain the math on the relative spring rates in their system and not certain whether I believe or not that the springs are never at full compression concurrently, but I do know in direct side by side comparison, the Nemo system has a notably reduced recoil impulse sensation compared to equivalent weight conventional reciprocating mass.

Since the Nemo gear is all internal to the tube, there are no undue compromises forced on stock position.

 

[David Hoback]

I run a sound mitigation H2 buffer & prefer an adjustable gas block. Setting up proper gas for a specific load is the best way to control the system. The beauty of limiting gas pressure, is controlling the buffer so it never slams the rear of the buffer tube.

I do appreciate the OP’s thinking. Although, the buffer not not in constant contact with the shock absorber is sure get a beating! Possibly damaged? If it were to come apart, it could obstruct operation.

 

[Nicky Santoro]

No offense to anyone posting, but this is a solution in search of a problem.

 

[citizenconn]

I see this as being useful in the overgassed AR10s

I just use adjustable gas blocks instead in AR-10/308s. More useful for a variety of reasons.

 

[RainDodger]

Not sure if they're still made, but it's not a new idea. I have one I purchased maybe 10-12 years ago, made for an original A2 rifle. It still works just fine... it's just about like the pneumatic cylinders that hold up the hood on your car. Yes, it's quieter than a spring. Rarely shoot it anymore, as it's in a carry-handle A2 and my eyes tend to like scopes these days.

 

[N555]

I see this as being useful in the overgassed AR10s

Most pistols and "carbines" are way over gassed, especially if they have a silencer, like me.
Rifle setups seem to handle silencers pretty well. I might try and add a tungsten weight to my rifle buffer and then make sure it still cycles my rifle handloads, M855 over the speer13 max load of w748, should cycle.
Midlength 16 inch barrels, pretty over gassed, add a silencer then you are way over gassed. Even with my "carbine only load", 55gr fmj-bt which is 22.5gr of h322 (start load), overgassed even with a vltor H4 buffer and A2 rifle spring.
A 16 inch carbine upper, stupid over gassed with a silencer.
I stole a load off here: https://www.thehighroad.org/index.php?threads/clandestine-5-56-223-loads.889873/
I barrowed a 1/4 cup of RE7 form my 45-70 loading buddy and tried loading some up.
They were very accurate, and just like that my 16" carbine was barely to not at all over gassed.

 

[N555]

No offense to anyone posting, but this is a solution in search of a problem.

Guess you don't have any suppressed AR15s.

 

[N555]

I run a sound mitigation H2 buffer & prefer an adjustable gas block. Setting up proper gas for a specific load is the best way to control the system. The beauty of limiting gas pressure, is controlling the buffer so it never slams the rear of the buffer tube.

I do appreciate the OP’s thinking. Although, the buffer not not in constant contact with the shock absorber is sure get a beating! Possibly damaged? If it were to come apart, it could obstruct operation.

These things get pounded for hundreds of thousands of cycles. Only time I have see one break is when something else breaks and causes the tip of the shock absorber to shear off. I suppose it would break in a rifle if some one uses their rifle to poke a landmine or some sort of unexploded ordnance and sets it off. Then it would break.

 

[N555]

Still going strong. I remade my buffer tube but drilled and threaded it this time and did it all on a lathe. The original was a hole hand drilled with a nut inside and a nut outside the tube. It's just easier to set the depth with a threaded tube and nut.
I'm going to take the original tube and thread it for the bigger 12mm strut, just to try it.

 

[N555]

The cheap black oxide AR stoner LR308 buffer is back in stock at gouge way usa dot com.
I got the stainless $40 one as seen in the picture because the cheap one was out of stock everywhere. The cheap black oxide one is half the price.

I forgot to add this is one of the works I was reading when I came up with this.
https://www.thehighroad.org/index.php?threads/eliminating-ar-buffer-twang.873904/
Plus who puts grease on the buffer spring, gross. And yes I do get sand storms here usually every year.
That's one of the reasons I tried the JP, but it's expensive and not heavy enough.

 

[N555]

Forgive me highroad for I have sinned. Last night I chucked up a valtor A5 tube on the lathe, drilled and lathe tapped it for 10x1mm threads and installed the hydraulic strut.
Paired it with a standard carbine buffer, H3 weight and A2 rifle spring, as it's a 16'' midlength with silencer a bit over gassed.

Next I'm going to try a standard carbine buffer in H4. But you might be thunking there's no such thing as an "H4 carbine buffer". Well yea, but no. If you clone a standard carbine buffer out of stainless steel, instead of the usual aluminum and fill it with tungsten you would get about an H4 and then some, as now the empty buffer body weights about 4x as much as the aluminum one.
An all steel buffer is a good way to get an H to H2 buffer without any using any probably chicom made tungsten.
Ordered a Brownells steel body buffer last night.