I think it is pretty clear that the Mk12 is supposed to be in whatever cartridge everyone else is carrying for logistical reasons not just on a large scale but on a small scale unit basis. If in this hypothetical scenario DOD changes everyone to the cartridge of choice....well that is a whole another can of worms. But regardless of the chosen cartridge, no matter if it is 5.56, .308, 6.5G, 6.5CM, .224Valk, etc. (outside of the new poiy case stuff) the ideal mk12 would be:
- Based on the AR10 or AR15 or the "hybrids" out there like the DPMS G2.
- Use DI/Stoner Gas System operation.
- Use a proper gas port size and placement for optimized use with a suppressor, but be able to run without one.
- Use a gas block seal like LMT's or KACs.
- Use an Inconel gas tube like V7s.
- Use an enhanced bolt like LMTs or KACs, and enhanced carrier like LMTs.
- Use lithium alloys like 2055 and/or 2099 for the receivers, extensions, handguards, etc like Hodge and V7.
- Use a monolithic or enhanced upper to ensure handguard doesn't torque barrel nut, and for easier use with NV like Seekins, LMT, or Larue.
- Use a Bartlein or similar high end cut-rifled barrel, gain twist, nitrided, using 5/8x24 threads. Length would depend heavily on cartridge chosen but I don't think any of them should be longer than 16in-18in or so max.
- Use a JP (finished BAT) barrel extensions.
- Use a Vltor A5 buffer used with Tubb's flatwire spring.
- Use a LMT's DMR stock or something similar that can be collapsed for use with armor but also offer a cheek piece and increased stability (the new B5 might be similar).
- Use a An AEM5 (or AEM30) made from titanium and with a flash hider "end cap."
- Use a quality two stage trigger like an SSA-E.
- Be issued with some quality match ammo, but be able to run whatever standard issue is.
Would basically improve on the current iterations in every way (depending on cartridge): weight, length, accuracy, durability/reliability, and so on. No one currently makes a rifle like this but KAC, LMT, and JP are closest.
