While I can appreciate the durability of newer ARs, I've seen that video before and with the exception of the explosive test I have issues with every other test they did.
1. Dirt test - The dirt they covered it with is nowhere near as fine grained as the "moon dust" crap in the middle east that gets all over everything and in every nook and cranny.
2. Water test - Anyone in a combat zone who falls into a canal or has a vehicle rollover into a river isn't going to have time to tape their barrel. At best, they'll be able to rack a new round and drain the water and hope there's no silt clogging the end.
3. Shotgun test - They shot it with birdshot. I'd like to see how it does against buckshot. Or ricochets/glancing shots from a 7.62x39, which is what it's most likely to get hit by.
4. Vehicle test - A Jeep Wrangler weighs about 3500 lbs. An up-armored Humvee weighs upwards of 12,000 lbs or more depending on armor kit and crew loadout. MRAPs weigh even more. I've seen M4s run over by lesser kitted up-armored Humvees and it bent the rifle into a slight banana shape and completely crumpled the rails. To be fair, there ARE plenty of Jeep Wrangler-equivalent civilian vehicles driving around in Iraq/Afghanistan, but...still.
5. Explosives test - This is the one test I feel they actually did really well. It simulates a soldier walking along and getting hit with an IED that may not kill him or her, but IEDs are sometimes accompanied by small arms fire where the soldier would need to return fire immediately after getting hit. There's some videos on YouTube and LiveLeak of that exact scenario happening.
6. Drop tests - Well, first of all, you're dropping it onto grass and dirt...as opposed to hard rocks and concrete. Secondly, you just blew it up. The force of the explosion is far more than a 100 ft drop from a helicopter onto grass.
All in all, an effective marketing video, buuuuuuuuut...that's all it is.
I counter with HK's 416 video...which shows similar testing to the water test from Daniel Defense, but improved.

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