What 5.56mm Nato loading is the US Army using now?

[Lone_Gunman]

is it the ss109 62g?

or something in 55g? if so, what is the M designation.

 

[Quintin Likely]

As far as I know, SS109 is still the standard issue, with smatterings of MK262 in special forces groups.

 

[NMshooter]

M-855 ball 62gr. (with the green tip) standard issue. M-193 ball 55gr. still issued to some National Guard and Reserve units (and some Air Force units). Mk 262 mod 1 OTM (open tip match, 75 or 77 gr. Hornady or Sierra can not remember which) limited issue to some units.

The ammo oracle in the ammunition forum at AR-15.com has much greater detail.

 

[VG]

http://www.fas.org/man/dod-101/sys/land/556.htm

AR-15.com is Wilson Combat. I think you mean http://www.ar15.com