Can you do me a favor tell me how much the reciprocating mass weighs?
Thank youGive me an hour or so
No problem. Thank you very much!Sorry, got stuck at work late
1lb 8.8oz
Trying to make my POS mdr work. It seems like it has a similar gas port location to the scar but the reciprocating mass is only 13oz. Despite assurances from DT that it was fixed each of the THREE times I've returned it to them it still doesn't run. Short strokes and stuck cases.So what's the project you need the info for ?
DT just put a video out about the MDR issues with specific ammo used and gas block settings. Apparently you will be getting a new gas block on them. Search youtube and you will find it.
What I dont understand is they explicitly state the ammo the gun was designed for. It should work with all brands of ammo. A big failure IMO and very drastically limits who uses it.
I have 10-15 clicks of adjustment on my SLR gas block and can run 150s to 178s no problem with fine adjustments. Internals are different for sure, but having a fine adjustable block would ensure all types of ammo can be ran instead of a course adjustment that limits range.
Sure, but if you tune too wide you get folks bitching that the gun is over gassed. See all the SCAR re-jetting conversations, and DD MK18 overgassing issues that have been discussed.
The way the mdr is set up it has a narrow operating range. Enough gas to reliably cycle the action and ejection system is on the edge of ripping case rims off and it eventually does when it gets dirty enough. It unlocks too early. It's easily the dirtiest operating firearm I've ever seen. Go a click down on the gas adjustment and it doesn't have enough bolt inertia to operate properly.
I'm aware of the issues with the MDR. I saw their response video, and I hope the new valve works better for folks.
I guess the points I was trying to make:
1. Ammo is highly variable in quality.
2. A gun company typically gets blamed when their firearm doesn't cycle horrendously out of spec ammo.
2a. Gun companies proactively "overgas" to quell the whining of people shooting under spec steel cased ammo in $3000 rifles
2b. Because of 2a, people who shoot in spec ammo, or shoot suppressed complain about guns being over gassed
3. Gun owners will bitch about anything
4. Giving consumers more ways to adjust the gas system doesn't == nirvana. Usually quite the opposite. Typical consumers have no idea what they are doing, or why. They are monkeys with hammers working on watches.
Yes these are all broad brush statements. I stand by that on average, they are accurate.
All mostly valid but the mdr absolutely needs adjustment to fire different types of ammo. Take any typical ar-10 with the same ammo and it just works. The design is flawed.