What's the black magic involved in DD's Mk18?Originally Posted by John Hearne
All I know is that it's svelte to handle, reliable, and shoots as softly as my 14.5" BCM middy.
The time it takes me to get two shots on a 25y steel plate with the legacy Mk18, I can put 5 on target with the Daniel Defense Mk18.
"Are you ready? Okay. Let's roll."- Last words of Todd Beamer
Rifles belong up front in LE vehicles. The one instance I’ve found where short barrels are a real advantage is deploying from within or out of vehicles.
Nothing wrong with suppressed guns but on an issued gun, set it up suppressed (reduced gas port) and run it suppressed all the time.
can't speak to the former, but agree on the latter.
For an agency, that might be easy-ish to do (although 40 guns/uppers might not be enough to get the attention it would require), but again I may be out of touch with the industry. Getting a particular barrel/suppressor/ammo combo to work together *and* getting people to stick to that combo used to be pretty hard to actually make happen, hence my original threadjack into adjustable gas blocks (and just so we don't have to keep beating on that horse, I'd like to reiterate that I agree with you about not putting them on issued guns).
What type of environment does your agency patrol? Urban or rural, or a mix of both? You mention wanting good terminal effects out to 200 yards. For most LE agencies, 200 yards is a long shot. Unless the officer is taking direct fire, identifying and justifying lethal force from 200 yards away could be a challenge. Especially in today's legal environment. In my agency, it's mostly urban to inter-city. The majority of armed threats are well under the 50 yard range, and I'd say mostly under 25 yard range. At these distances, you don't loose much by going to the SBR over the 16" guns.
SBR's are easier to deploy when exiting a vehicle under stress. But when we started switching from the Crown Vic's to Explorers, the larger door of the Explorer makes it easy for me to roll out with my 16" patrol rifle. So it depends on what type of vehicles your agency is fielding, and how much crap is inside of these vehicles, as to how much of a benefit converting to SBR's would add.
If your officers are doing mostly perimeter work with their rifles, the 16" barrels are just fine. If it's more building clearing work, then the SBR may be the way to go.
If you do decide to covert your existing guns, I would use 11.5" barrels instead of the 10.5's. The extra inch is definitely worth it for the almost 40% increase in dwell time and decrease on the wear and tear on the guns. Longer dwell time will increase the reliability of the gun.
There is also the ugly but ever present issue of cost. Do you have the funds in your budget to convert 40 guns? If so, then I'd strongly consider buying 40 11.5" uppers and being done. If money is tight, then you might make a convincing argument that buying new uppers is cheaper than buying new rifles. Or convert a number of guns per year, as budget permits, until your entire inventory is converted. Starting with the oldest guns with the most rounds through the barrels.
I just wanted to drop some more thoughts. By the time you suppress an 11.5 you're at or near 14.5/16" guns depending on suppressor length so maneuverability is about the same. If your department doesn't get suppressors whether you're going to 10.5-12.5" you're still going to have a flashing attached to the end of your muzzle. You may not get suppressors with the added costs. I'd plan for that since budgets are a thing for most departments. (I'd present both plans, 11.5's with suppressors and 14.5's). If I knew I would get the shorter barrels and suppressor and was in a more urban environment then I'd get the 11.5's and suppressors but if that's not likely I'd go with the 14.5's get better ballistics increased terminal performance at longer ranges and not be blowing everyone's ears out. You'd also be reducing cost and would probably be easier to sell. Also I believe it was Pressburg who mentioned another advantage for the 14.5" is being able to work the barrel out past intermediate barriers like a windshield which makes a lot of sense for LE running one from inside a vehicle, (maybe not highly likely but still possible).
Another consideration is ammunition. Whatever your current duty ammo choice is for 16" guns, may or may not perform as well out of a 10.3/10.5" barrel. More often than not, ammunition that performs well in 16" guns will over-penetrate out of 10.5" guns.
So if you ended up running both barrel lengths, as many departments do around here (16" for patrol, 10.5" for SWAT), then you will likely end up needing to purchase two kinds of ammunition.
Last edited by StraitR; 08-10-2019 at 03:26 PM.
The MK18 is an intentionally designed, vetted, and tested solution for a less than 11.5" gun. It's been a proven over gassed solution that will run at the cost of long term durability. And realistically, it's a 10.8" barrel - that's less than half an inch shorter than an 11.5" upper.
Last edited by John Hearne; 08-10-2019 at 03:26 PM.
- It's not the odds, it's the stakes.
- If you aren't dry practicing every week, you're not serious.....
- "Tache-Psyche Effect - a polite way of saying 'You suck.' " - GG
Yeah, I get that.
I was asking what makes the Daniel Defense Mk18 so good compared to other 10.xx" guns. You stated you wouldn't take a 10" gun unless it was a true-to-god Daniel Defense. Why?
He already stated Speer Gold Dot 62gr, which is fine out of 10" guns out to ~200 yards.
Last edited by TGS; 08-10-2019 at 04:02 PM.
"Are you ready? Okay. Let's roll."- Last words of Todd Beamer
I did a poor job of reading his thread, didn't I. Kind of jumped right into the responses.
In that case, I would suggest the OP have their local Speer rep come by and do a demo shoot (all protocols), with multiple (different) lots of 62gr GD to ensure they see what they want to see.
Last edited by StraitR; 08-10-2019 at 04:57 PM.
One thing to consider is even on agency guns you must do ATF form 5s and add your ARs to the NFA registry to SBR them. This could also be extra work if you wanted to trade or sell them later,
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