Recommendations for an adjustable gas block for DDMK18?

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[ARCHIVED THREAD] - Recommendations for an adjustable gas block for DDMK18?

Posted: 3/29/2017 3:33:48 PM EDT

I know this has been asked here before but the last post I have found was from 2015 so I wanted to re ask this question in case any better options are now on the market. So typical DD MK18 issue, the 10.3 inch barrel spews hot gas in the face when shooting suppressed. The consensus on a solution seems to be buy an adjustable gas block. What do you guys recommend?

Bonus question - I get a jamming issue probably once every 20 rounds. Also, the brass is very very dirty coming out of the rifle. Rifle is cleaned and well maintained, I'm using brass PMC .223 ammo with my SilencerCo Omega attached via QD. Would fixing the overgas problem also solve the jamming issue or is this something else and what recommendations would you have? I'm thinking about going to only 62grain 5.56 ammo I've heard it likes that bullet weight the most.

Thanks in advanced

Posted: 3/29/2017 4:36:43 PM EDT

[#1]

I just addressed a similar situation on my suppressed 10.5 SBR. I knew it was over gassed even without the suppressor but the suppressor made it chuck brass at 1 o'clock or less and the brass looked almost like grey steel case on the ground. This is a Noveske barrel with a pinned gas block so I tried an adjustable gas key. This didn't do much to resolve the issue. So I tore the upper apart and put on a Superlative Arms bleed off adjustable gas block. This combined with tuning the gas key has made this gun run like it should and much cleaner. Brass now ejects at 4 o'clock in a neat pile with less discoloration to the brass. YMMV.

Posted: 3/29/2017 4:50:41 PM EDT

[#2]

It is possible, if not likely, that the function issue is over gas related.

I haven't had personal experience with Superlative Arms' adjustable block, but everything I have hear has been good. I have used SLR"s so far, with good results.

Another option would be a Gemtech adjustable bolt carrier group or a Bootleg adjustable bolt carrier group.

Either the adjustable block or bolt carrier,option will have you rifle shooting cooler, cleaner with less and smoother felt recoil and a slower cyclic rate - likely source of your jamming issue is too fast a cyclic rate. Bolt life and brass life will be extended and fired brass as well as unfired cartridges in the mag won't look so dirty either.

JPK

Posted: 3/30/2017 9:32:57 AM EDT

[#3]

I have also used an SLR adjustable gas block on my 7.5" AR and have had nothing but good experience.

Posted: 3/30/2017 12:20:44 PM EDT

[#4]

Micro MOA gas blocks are a good option and they have ports set up for this specific application.

If you're shooting suppressed your brass is going to be filthy. No way around that, it's normal.

What buffer are you running? I have a H3 in my DDMK18 and it runs great.

Posted: 3/30/2017 3:33:32 PM EDT

[#5]

I know MicroMOA makes an adjustable block (plates) specifically for the DD Mk18. However, they haven't been in stock for sometime now. Anyone know what's going on there?

Posted: 3/30/2017 5:15:29 PM EDT

[#6]

I'm going to check that when I get home. I called DD to ask for a recommendation as well and they said don't do the gas block. They want me to check the buffer first and if it is H-H3 then send it in and they will tune it to work properly. Figure I'll give that a try first then if it doesn't help I'll go to the gas block.

Posted: 3/30/2017 6:49:31 PM EDT

[#7]

A heavy buffer is a bandaid, reducing gas is a cure.

If you post a Q to MicroMOA via there contact page you will get a reply. The owner has been dealing with some family health issues.

JPK

Posted: 3/31/2017 12:35:18 PM EDT

[#8]

MicroMOA Govnah, SLR rifleworks, Superlative Arms or JP gas block if you want an iron sight.

Posted: 4/4/2017 10:49:03 PM EDT

[#9]

SLR on mine. Made a night and day difference. Using factory H buffer. I have it set pretty low. Will not cycle without my Surefire RC2. But i have zero intentions of shooting the gun without the can on a regular basis.

Posted: 4/7/2017 7:04:58 PM EDT

[#10]

I have the black rain ordinance branded syrac adjustable gas block and love it. I would not bother with the adjustable bcg's. All the gas and carbon still will end up in your face just a millionth of a second later. With an adjustable gas block or adjustable gas tube you restrict the excess gas from ever getting into your upper reliever. I would try either the syrac ( I love it) or the slr ( I have heard nothing but good things)

Posted: 4/8/2017 7:31:37 AM EDT

[#11]

I've been quite happy with my SLR Sentry 7.

Posted: 4/18/2017 8:37:47 AM EDT

[#12]

Love my SLR on my factory DD mk18 upper. Really made the gun smooth and fun to shoot again. Way too over gassed from factory!!

Posted: 4/18/2017 11:54:40 AM EDT

[#13]

For those with an SLR, what are the different settings/port sizes? I can't seem to find it on their website.

Posted: 4/18/2017 4:36:31 PM EDT

[#14]

Got this response from DD. Very pleased with how they handled it as long as it works (see response in pic linked)

http://m.imgur.com/5r3gScH

Posted: 4/18/2017 8:29:24 PM EDT

[#15]

Quote History

Quoted:
Got this response from DD. Very pleased with how they handled it as long as it works (see response in pic linked)

http://m.imgur.com/5r3gScH

View Quote

Dude hell ya! Great CS there.

Posted: 4/18/2017 11:09:48 PM EDT

[#16]

I got one of the micromoa govnah gas blocks modified for use under the mk18 rail.

Installed it myself, and it's fantastic.

I should have just started with it instead of trying a suppressed bolt carrier and other band aids.

Posted: 4/19/2017 11:06:07 AM EDT

[#17]

Quote History

Quoted:
Got this response from DD. Very pleased with how they handled it as long as it works (see response in pic linked)

http://m.imgur.com/5r3gScH

View Quote

Wow, that is rockstar status customer service!

Posted: 4/21/2017 6:52:24 PM EDT

[#18]

Quote History

Quoted:
Wow, that is rockstar status customer service!

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
Got this response from DD. Very pleased with how they handled it as long as it works (see response in pic linked)

http://m.imgur.com/5r3gScH

Wow, that is rockstar status customer service!

Nice. Might have to go the route once my stamp is back.

Posted: 4/25/2017 1:08:56 PM EDT

[#19]

Quote History

Quoted:
Got this response from DD. Very pleased with how they handled it as long as it works (see response in pic linked)

http://m.imgur.com/5r3gScH

View Quote

Thats great but why don't they just sell the military/law enforcement version

Posted: 4/27/2017 7:26:47 AM EDT

[#20]

Quote History

Quoted:

Thats great but why don't they just sell the military/law enforcement version

View Quote

Probably because they'd get a lot of returns from customers who don't even know what a gas port is for failures to cycle with weak, commercial .223.

Posted: 4/27/2017 3:32:39 PM EDT

[#21]

DD has some of the best CS in the game.

I have personal experience with the DD 10.3 and SLR Adj blocks.

The first version they had blew up on me one day (and others)

The newer version Sentry7 is also now seized up and doesn't move. Also was once fine tuned with my specwar 556, but has consistently opened up and now im over-gassed again.

Thought about trying the microMOA, but it looks like they are out of business now.

Posted: 4/29/2017 12:03:56 AM EDT

[#22]

Quote History

Quoted:
DD has some of the best CS in the game.

I have personal experience with the DD 10.3 and SLR Adj blocks.

The first version they had blew up on me one day (and others)

The newer version Sentry7 is also now seized up and doesn't move. Also was once fine tuned with my specwar 556, but has consistently opened up and now im over-gassed again.

Thought about trying the microMOA, but it looks like they are out of business now.

View Quote

@amphibian

Posted: 4/29/2017 1:39:44 PM EDT

[#23]

Quote History

Quoted:
Got this response from DD. Very pleased with how they handled it as long as it works (see response in pic linked)

http://m.imgur.com/5r3gScH

View Quote

@vv83
Have you been able to shoot it yet? If so, can you give us a rundown on how this setup worked? Thanks in advance.

Posted: 5/5/2017 1:58:01 AM EDT

[#24]

Part of DD's reply to my email:

We are currently manufacturing mk18 rifles and URG’s with the mil-spec gas port diameter. I wish I could sell you one directly, however, we have cut off our internet sales so that we can better support local dealers who are trying to obtain our product.

If you do purchase a mk18 URG and it has the commercial gas port we will gladly get that URG back in house and install the mil-spec barrel with the mk12 gas block which is what we are currently using for this build.

View Quote

Posted: 5/5/2017 12:06:20 PM EDT

[#25]

The response I got when I asked about countering over gassing when running suppressed with mil-spec ammo.

Quote History

We went with the commercial gas port size on that particular rifle.
As far as countering the over gassing when running suppressed. I would recommend installing a heavier buffer and buffer spring.

View Quote

Posted: 5/5/2017 1:29:55 PM EDT

[#26]

Richard at DD replied after I expressed concerns with a bandaid solution. I'm okay with this.

When you receive your MK18 try it out suppressed and if you have any issues we would be glad to bring it in free of charge and correct the issue for you. Turnaround time would be 10 to 14 days.

View Quote

Posted: 5/5/2017 1:38:44 PM EDT

[#27]

Quote History

Quoted:
Got this response from DD. Very pleased with how they handled it as long as it works (see response in pic linked)

http://m.imgur.com/5r3gScH

View Quote

My experience with DD customer service has always been awesome, but this is over the top.

[ARCHIVED THREAD] - Recommendations for an adjustable gas block for DDMK18?

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