So with PPU 55 grain ammo I averaged 1. In the bolt carrier, the cotter key firing pin retainer has been replaced with a captured pin that stays with the carrier. Copy the SKU into a google search to see some actual photos. The program commenced in June of These soldiers wanted a rifle that was extremely reliable, required little maintenance, would work in all environmental conditions and function with or without a sound suppressor. The sling hardware is Magpul, the magazine is steel and is an HK. Everything else is kinda irrelevant. I'm willing to be the HK is probably as good as it gets in that department. So lets get to it. Alex C. Please click the green box stating it as the best answer. This is to be a lightweight magazine fed rifle that was to replace the heavy belt fed M This is the same key feature critical to the success of the HK rifles used by leading military and law enforcement customers. The firing pin is held in place by a lever that only is disengaged when the top of the hammer lifts the rear of the lever allowing the firing pin to move to strike the firing pin. Is it 3rd best because of lack of folding sights and proprietary pins?