Radical Firearms Forged Milspec Rifle Semi-Auto 6.5 Grendel 16" Stainless Steel Match Barrel Medium Contour 1:9 Twist Mid Length Gas System B5 Stock Grip Pepper Pot Brake 15" RPR M-LOK Handguard 1-15 Rd Mag Black Finish

Designed by Bill Alexander in 2003, the 6.5 Grendel is based on the 7.62X39mm case necked down to take a 6.5mm bullet. Designed for the AR platform, the intent was a military cartridge that would provide greater knockdown power than the 5.56X45mm. As with the several other potential replacements for the 5.56X45, the 6.5 Grendel has not found favor with the military, but with a 123-grain .264-inch bullet at 2610 fps it has a following in the AR community as an accurate and effective medium-range hunting cartridge. Conversion of existing ARs to 6.5 Grendel is a simple matter of swithcing out an upper receiver. — Craig Boddington