[Newton]

I'm having trouble finding some good information on these new 5.56mm rounds. All I can establish is that they are some kind of new long range sniping round for military M16/M4/AR type rifles in the 77 grain weight range and with a BTHP (OTM) configuration (not sure about the HP part).

Where are we up to with these rounds, are they accuracy only deals, are they field issue yet, does the HP open up, has testing shown unexpected performance benefits for the shorter M4 style weapons - what ?

Thanks in advance.

[Bartholomew Roberts]

Newton, check out the Ammo forum under AR15s at AR15.com. It has a tacked post discussing the Mk262 Mod I ammo.

There are terminal performance increases for all 5.56mm weapons with this round as I understand it.

The Mod 0 used the 77gr Sierra Match King Open-Tipped Match round.
The Mod 1 uses a 77gr. Nosler Open Tipped Match Round (Georgia Precision is selling some Black Hills ammo loaded to Mk262 Mod 1 specs)

The Mod 0 was used in Afghanistan and I believe the Mod 1 is being used in Iraq.

The round doesn't open up. It is a match hollow point and isn't designed to expand - the open tip is just a result of how the jacket is applied. It fragments similar to military FMJ ammo; but does so more violently (bigger round), more reliably, and at lower velocities.

[Newton]

Good info., thanks BR.