DD MK18 Range Report

AR/M4 AR General Discussion
1

First time out with my DD MK18, pictured below, and was impressed with the setup.

I took some extra buffers as I wasn’t 100% sure the VLTOR H4 in the VLTOR A5 system would function 100% with a variety of ammo.

The good news is with PMC Bronze, XM193 and my medium-ish power 4198 55gr hand loads the setup functioned flawlessly with the VLTOR H4 and recoil was negligible. The bolt locked back on the last round every time, with every round shot. The bolt picked up rounds very smoothly and didn’t have a single hiccup.

The rifle:

DD MK18 Upper
Spikes Lower
ALG ACT trigger
Colt LPK
VLTOR A5 RE - Spring and H4 buffer
VLTOR EMOD Stock
Troy Micro HK flip sights

The Target:

Distance: 100 Yards
Iron Sights: (At my age I can barely see the target at 100 yards, so cut me some slack when using irons please)
Cartridges: 20.5gr IMR 4198 / 55gr Hornady Soft Points

2

I love the florescent safety markings and spikes spider dick on the lower. It compliments the white DD billboard on the upper. The 6" groups look good too.

3

Looks good.

4

If you have nothing of value to add I would appreciate you not soiling my thread with your tripe.

5

How many rds did you end up firing? Was it your first time shooting with this gun/upper?

6

I also have a factory DD Mk18 upper running on a stock LMT defender lower with carbine buffer and it has never had a hiccup. Time to paint yours.

7

I would love for anyone else running a DD MK18 upper to weigh in on their chosen buffer / spring combos. There seems to be a lot of variety with the H2 and standard spring or sprinco blue leading the way. I must admit, the A5 system is intriguing.

8

I’d love to see a picture that shows the entire weapon OP.

And I 2nd that it’s time to paint it.

9

With a gas port of .083" on the DD MK18’s the VLTOR is about the only option. The spec is .071-.073" on a 10.3" barrel and DD chose a .083" for the ability to shoot TULAmmo, this means with anything less than a rifle system(or VLTOR) you are looking at horribly reduced bolt life and less than stellar reliability. My MK18 when I had it snapped the bolt lugs around 5,000-6,000 rounds and probably had 1 FTE every 70 or so rounds. My LMT(which uses a .071" gas port) has performed significantly better all the way around. This is with a carbine spring and H2 buffer fyi.

10

Were you running an A5 in your rifle when you had it or something else?

11

Yep, when I had the DD MK18 upper it was on my A5 lower. My LMT is on my basic carbine lower with a H2 buffer. Even with the A5 the DD upper was insanely overgassed, that is why I think the A5 is a must have when using the DD upper.

12

Most of the shots went into at least the eight ring…you done good, sir.

13

Yes A5 with H4 VLTOR buffer.

Most of the reason for the post was to document the function of the A5 H4 buffer with this upper and the PMC Bronze which is about the lightest load I ever shoot.

14

That A5H4 buffer is an awesome option to have. Thanks for the report.

15

Where did you find the DD rail covers? I didn’t seem them on their website. Good shooting with irons at 100yrds.

16

They came with the upper…the upper I bought earlier in the year came with “normal” ladder style rail covers. I was surprised this one came with something different.

Thanks for the compliment, at my age, shooting irons, the target is a blurry blob in the background there is little to no precision involved. I wish I still had my 20 year old eyes. When I shoot for groups at any range I am forced to use an optic anymore.

Perhaps I should start a thread on tips for shooting irons when you’re 50+…

17

Yes, first time with this upper / lower SBR. I shot a total of 120 rounds. 50 hand loads and the others were sighting in the irons with PMC / XM193. (Not pictured)

I appreciate the feedback on the red spider, but I paid extra for that! :slight_smile: (Joking of course)

I’ll snap a quick shot of the entire rifle and post it up, but it won’t be the same quality as the other pictures.

I lied, this one is fairly high quality as well.

18

Wow, definately overgassed. Instead of going with special buffers and springs, wouldnt it be easier to use an adjustable gas block such as the SLR or Syrac and not worry about it?

Sent from my SAMSUNG-SGH-I747 using Tapatalk

19

Perhaps…Personally, I like leaving things stock, to the extent possible.

20

So, to what degree should one expect a blue Sprinco spring and H3 buffer to mitigate undue wear? That is what I currently have in my DD Mk18 pistol.