From what I have read and been told the introduction of the 700 Mil Spec rifles came about mainly brcause Remington had barrels that did not meet the full requirements needed to meet the M24 and M40 standards. These barrels were turned down to Remington's Varmint contour and then coupled to a 700 action. The stock is a HS Precision with alum bedding block. These rifles were them sold as limited runs. The Mil-Spec refers solely to the 5-R rifling profile designed by Boots Obermeyer and used in the single broach-cut barrels he produces for use in the M24, M40, and other sniper rifle systems. The contour of the hammer-forged production Remington barrel is much thinner than that used in the M24 and M40 rifle systems. The 700 Mil Spec rifle have been sold in .223, .308 and I believe .300 Win Mag. The .223 has a 1 in 9 twist, compared to a normal 700 which has a 1-12 twist.