Anyone running a DDMK18 Suppressed?

[mkollman74]

I believe the RC2 and MK18 were purchased by SOCOM as a package that was supposed to work quite well together. Also, here is a good article.

Surefire SOCOM556-RC2 5.56 AR15 SBR Suppressor Test — PEW Science

Surefire SOCOM556-RC2 5.56 Silencer Test with first round pop data. Real sound signature data with the Suppression Rating from PEW Science. Hearing Safe determinations for your use case. How does it do as a 5.56 SBR suppressor? Can it suppress 5.56? Is the Surefire SOCOM556-RC2 the best 5.56 AR1

pewscience.com

 

[benchmstr]

This one has probably close to 500,000 rounds through it with 3 suppressors and countless barrels..run it hard..it’s what it’s for.

To tell you how old it is? Still rocking a quad rail after all these years

 

[darkfader]

I love the Mk18. I have a Mk18 inspired build and run a Sandman S while I wait on the RC2 in jail. Currently only at a little over 100 days on that so it’ll be a while I guess. Love the rifle though.

I should add, I have the enlarged gas port and run an H2 buffer. Gas isn’t terrible unless I’m advancing on target while firing a string.

 

[Alexs15]

I love the Mk18. I have a Mk18 inspired build and run a Sandman S while I wait on the RC2 in jail. Currently only at a little over 100 days on that so it’ll be a while I guess. Love the rifle though. View attachment 8194785View attachment 8194786

I should add, I have the enlarged gas port and run an H2 buffer. Gas isn’t terrible unless I’m advancing on target while firing a string.

I’m working on a build that’s all FDE. Did you cerakote the rail?

 

[darkfader]

That’s actually MolyResin from John Norrell. Stumbled onto that looking for an accurate “Colt Grey” from the Vietnam era M16. It’s good strong stuff, applied with an airbrush and cured in the oven. I have several colors and they are accurate.

 

[benchmstr]

I love the Mk18. I have a Mk18 inspired build and run a Sandman S while I wait on the RC2 in jail. Currently only at a little over 100 days on that so it’ll be a while I guess. Love the rifle though. View attachment 8194785View attachment 8194786

I should add, I have the enlarged gas port and run an H2 buffer. Gas isn’t terrible unless I’m advancing on target while firing a string.

I’ve never had to enlarge a gas port or use an adjustable gas block..just a Jp flat wire buffer spring and spikes ST-t2 buffer..I started doing that a long time ago and all my personal SBR’s have that setup

 

[darkfader]

I could be misinformed, but I believe the real Mk18 barrels were configured with a larger gas port than normal due to the shorter dwell time. I didn’t enlarge my gas port, I bought a barrel that was a clone of the original Mk18 barrels and advertised to have the larger port. No idea if that’s necessary or not.

 

[Diesel79]

.070 is the Crane Spec for the MK18 gas port. The older DD MK18’s had a larger port, but I think 2018? forward has the .070.

 

[darkfader]

Gotcha, mine is .070”.

 

[houndog]

I shoot my MK18 suppressed almost 100% of the time. Run a Sandman S and a Trijicon MRO red dot. I believe I either have an H2 or an H3 buffer. Gun is pretty soft shooting, and I've run 1000+ rounds through it. Don't think I've ever had a FTF/FTE, including when I've shot in subzero temps.

 

[Chicory01]

This one has probably close to 500,000 rounds through it with 3 suppressors and countless barrels..run it hard..it’s what it’s for.

To tell you how old it is? Still rocking a quad rail after all these years

>500k rounds

Do you shoot for a living wtf

OP: I've been running a MK18 for a couple of months, hands down my favorite SBR upper so far. The new (Post 2017) uppers have a .70 gas port, much softer than the older versions.

Get yourself a MK18 and shoot it.

 

[LRRPF52]

This one has probably close to 500,000 rounds through it with 3 suppressors and countless barrels..run it hard..it’s what it’s for.

To tell you how old it is? Still rocking a quad rail after all these years

It would be good to list the schedule you shot and when you replaced:

Extractor springs
Ejector springs
Recoil/action springs
Bolts
Barrels

From fleet data, there are reduced parts life that have been observed.

For those recommending adjustable gas at the gas block with set screw chokes, those will see erosion, which equates to opening the gas flow up into the system. SOTAR had a great video recently showing that on borescope on 2x 10” suppressed LE guns that had all sorts of problems (Black Rain Orifice).

They had huge ports at CLGS 10”, then tried to compensate for that with extra power action springs. Guns were beating themselves up badly, not working.

A good thing to remember about the whole deal was when SOCOM asked LMT to develop a solution, which was a regulated carrier, not choking the gas up at the block. The enhanced LMT carrier had additional gas relief to run the CLGS barrels more optimally.

I personally love the adjustability and approach with the Bootleg Adjustable Gas Carrier, which uses a flat head choke right through the ejection port. No need to remove the BCG, no need to fish into the handguard with tiny Allen wrenches, no set screws getting carbon-welded.

With a high-efficiency can, I run it fully-suppressed. You can watch the clock position of the ejection pattern change when you adjust the settings, so it really does regulate the cyclic rate noticeably.

 

[Diesel79]

This one has probably close to 500,000 rounds through it with 3 suppressors and countless barrels..run it hard..it’s what it’s for.

To tell you how old it is? Still rocking a quad rail after all these years

Half a million rounds and nary a scratch and no anodizing wear on the brass deflector?

 

[SilentStalkr]

Half a million rounds and nary a scratch and no anodizing wear on the brass deflector?

That’s a very good point. I never really looked at his pics! But after looking at the blurry pic again, that thing looks like a safe queen. It certainly doesn’t look like anything ive ever seen that’s been run remotely as hard as claimed. I suppose parts could have been replaced to make look new again or he is referencing this pic of the rifle before it had that many rounds on it though.

 

[darkfader]

I just got my RC2 a couple days ago. I put this pic in the AR15 thread but…gratuitous pic:

 

[metroplex]

500,000 Call of Duty rounds

That’s a very good point. I never really looked at his pics! But after looking at the blurry pic again, that thing looks like a safe queen. It certainly doesn’t look like anything ive ever seen that’s been run remotely as hard as claimed. I suppose parts could have been replaced to make look new again or he is referencing this pic of the rifle before it had that many rounds on it though.

No anodizing wear and brass marks on the deflector are a dead giveaway. Must have been 500k Call of Duty rounds

 

[hlee]

500,000 Call of Duty rounds


No anodizing wear and brass marks on the deflector are a dead giveaway. Must have been 500k Call of Duty rounds

Nah, he’s on his 5th barrel, 6th upper, 3rd lower, second stock, 3rd set of lower parts, and 5th muzzle device…

 

[Charmingmander]

Bait

This one has probably close to 500,000 rounds through it with 3 suppressors and countless barrels..run it hard..it’s what it’s for.

To tell you how old it is? Still rocking a quad rail after all these years