freddy
.308 Win
Here you go. Cheap too. Only $5 per round.308 is a bit of a waste in 16" but if you choose your ammo correctly
the 308 makes as much power as the two other combined.
See if you can find 155gr british surplus...
Otherwise winchester 147gr will give 200fps more than federal.
Other nato ammo might work better than lake city for that size. DAG possibly.
If you roll your own you can put a 175gr bullet to 2500fps or a 120gr to 3000fps with faster powders.
308 Winchester 125gr. Nosler Ballistic Tip 20rds.
If you don't mind spending a bit more then the 130gr TTSX from barnes comes out close to 3000fps from a 16" barrel.
Also see if you can locate the new M80A1. A friend has managed to get bullets but not the loads.
Those are also optimized like the Radway and they are 130gr arrohead like the 62gr M855A1.
ARMSLIST - For Sale: M80a1 epr 308 7.62x51 ammo