Unlike the M16, it does not blast gas and fouling directly into the bolt carrier. The six-lug bolt and carrier are of conventional design, riding back and forth on two hefty steel rails wrapped with stainless steel recoil springs. The SABR's carbine accepts standard M16 magazines. If necessary, the carbine module can be separated quickly from the rest of SABR by simply removing the captive pin that anchors it to the main housing. Since this is the part with the pistol grip and trigger already attached, the gunner is immediately ready to shoot.
Later development is likely to include some sort of rudimentary iron sights.
Indeed, an impressive system adapted specifically for the OICW has recently been installed at Aberdeen Proving Ground. Their candid feedback is being systematically collected and used for improvements to the system. Subsequent trials are to be conducted in jungle, desert and Arctic environments to see if laboratory results hold up in the real, muddy world of boot soldiers. Among reasons for this given by the Army and Alliant are the need to increase the system's capability and decrease its weight. Since we currently enjoy a peacetime disposition, this can be done in a methodical and cost-effective manner.