Suppressing the SOCOM 16
- muleequestrian
- 10 minutes ago
- 3 min read
One of my favorite rifles is the M1A (M-14) platform. I wasn’t issued one in the Marine Corps — we only had the M-16A2, not even the newer M-4 carbines they had for a while. These days the Corps uses the M-27 which operates basically the same way.
For a while I tried an AR-10 short barrel in .308, but the balance just didn’t fit me. I have a full sized M1A, and I like it a lot, but it’s a bit long. Then I found the SOCOM 16. For me — it fits like a glove. I’m a dinosaur I suppose for using an “obsolete” firearm by modern standards, but I can really ding the bullseye with this thing. Of course, there’s not a lot of accessories for this old war pig but I decided to add a suppressor to the old girl. I also opted for the lowest optics mount I could find, since I wanted to keep the cheek weld of the stock low without adding a riser. I chose the M14.Ca SHG handguard and scout scope.
My can of choice was what we had in stock at the gun store where I work, so I opted for a Yankee Hill Machine Phantom in titanium. I was going to need a quick detach muzzle device for it, so I opted to use a YHM attachment. Delta P Designs made a great adapter so I bought one. Unfortunately from what I’ve discovered, they shut down in 2023 and it appears they’re no longer available. There are other adaptors available, but I haven’t used them so I’m not posting here about them.
Here’s the difficulty of suppressing a SOCOM rifle. The gas flow needs to be reduced a slight bit because the suppressor builds up some extra pressure. The added over pressure can bend the operating rod and prematurely wear out an otherwise expensive rifle. I searched around for an adjustable gas piston system, and at the time of this project, one wasn’t available. So I had to improvise.
After some research, I bought spare spindle valves for my SOCOM. Normally these are reserved for ON/OFF for the grenade launcher function, but I’m NOT a tossing grenades from the muzzle. I drilled a hole across from the factory hole to reduce gas flow to the piston. There are many combinations of load, bullet, barrel length and suppressor design, so it is impossible to determine what will work best, the expectation is that 0.052″ is likely too small, and the bolt will not lock back on an empty magazine. Using a couple small carbide bits, you would drill a 0.052″ hole at the entrance, so you have a 0.052″ exit and a 0.054″ entrance, and try again. It’s a PITA, but the idea is to reassemble the gas system and test fire for function until you arrive at a hole size that allows the gun to function with the suppressor and just lock open on an empty magazine.
The spindle valve is cleaned out each time I tear down the rifle for a good scrubbing to prevent carbon build up from making it seize. The gas assembly is extremely hard, but I managed to scratch in a “U” and an “S” for Suppressed and Unsuppressed settings. The gun will not fully cycle on the S setting without the suppressor and it will short stroke.
Once everything is reassembled, the YHM QD muzzle adapter is installed with some Locktite, and is ready to go.
The only thing is to remember that when you remove the suppressor, you flip the slot of the spindle valve to the “U” position.