Tactical Life posts that the military is changing to the 6.8 in SAW and M4

[LRRPF52]

I just did a little "what-if" on their presumably min requirements of 3000 ft/s MV and 600 yd "effectiveness".
I used the .277 SMK 135 gr bullet, G1 BC=0.488 and 3000 ft/s.
Supposedly only a 6.8 will "meet Government requirements." Presumably X amount KE at 600 yds...
A 6.5 PRC, or a new "superdooper" powder and 6.5 Creed, with 143 (Eldx) at 2800 ft/sec gives 100 ftlb KE greater than their "270 NewWsm"...
At 600 yds, starting at 3000 ft/s, the 270nwsm has 72" drop, 1980 ft/s and 1175 ke.
At 600 yds, starting 2800 ft/s, the 6.5/ 143 Eldx will have 76" drop, 2013 ft/s and 1286 ke.
Of course all these nbrs are with a 24" barrel +/-... certainly not a carbine.

Granted this is a lot of assuming in here, but interesting that "da Gubmint" has made up its mind that only a 6.8 will do.

Still doesn't add up imo.

The overbore of the case width to bore diameter looks like a .270 WSM, so a 6.5 WSM would gas check the throat even worse than the ~1000rd barrel life threshold they're currently looking at.

One of the ideas is to let soldiers train with the rifle in virtual sims more than anything, with very rare moments of actual live fire, because it will expand the battle simulation centers even bigger than before. Those are huge programs with way more money in them than a rifle range.

The scary thing that this concept brings to light is that the first time some soldiers might actually fire this with live ammo would be in combat.