Yeah, my history with the MDR was an order for one chambered in 300BLK. Back then I had to order the MDR in something else (.223 wylde) and also order a conversion. I got disgusted after 5 years of waiting and cancelled the conversion with the .223 Wylde in hand (after 4 years). Built my own AR 300BLK after researching the (IMO) optimum build and never regretted it. It was more $ but IMO better all around. Since 300BLK subsonics can be tempermental as to build I expected to tailor my handloads to the gun and yes, they require tweaking. But ALL my loads get tweaked to every gun I load for. If I had waited for a working 300BLK conversion it would have been another 2-3 years (I stopped counting after requesting my refund). Looking back on it I don't think Desert Tech had a clue what was involved in a 300BLK conversion before they began taking $ for them.
My MDR is an anchor and I had no thoughts that it would be a lightweight even years before I received it, I knew what to expect so I'm not casting aspersions on it's weight, not really as a .223 Wylde. I didn't design my 300BLK AR build to be lightweight but it's still lighter even with it's can in place that's designed to handle .300 Win Mag, and if I remember correctly, still a hair shorter than my MDR with the can that's on it 24/7/365. It's a dense AR, deceptively heavy, but also built right. IMO the MDR would be too heavy for it's role as a CQB rifle. That's where I was going with this paragraph. But if I want a reliable extreme cold weather rifle the MDR is the one I choose due to it's massive internals and the tiny cartridge it pushes.
OK, a bit off subject... Why don't ammo manufacturers tell us what their 300BLK is ammo is designed to work with? I have factory ammo on hand that is clearly designed for manual actions. The few (one?) that works with a self loader designed for CQB, which is what the 300 BLK is designed for, claims to be suppressor friendly and it is. Supersonic is easy to make work in pretty much ANY 300BLK. The ammo boxes need more data on them IMO. That's if they care about actually selling ammo to the consumer who can use it. If they just want to sell ammo and piss people off they're doing it right. I don't want factory ammo that turns my semi-auto into a manual action. I don't buy factory ammo anymore, so their one time sale to me is their last sale to me. They made one minor sale, that seems sorta like not what they would want, or I wouldn't want that if I was in the factory ammo business. Whatever. I don't have $ invested in their businesses. They do. Those folks with bolt actions and single shots can use anything that fits in the chamber.
edit: (I forgot some stuff)
Recently they introduced the really short MDR. It seems tailor made to be chambered in 300BLK and that's the only way they could get me to do business with them again. Yet, last I checked it wasn't chambered in that. OK. I don't get it.
