The MK-18 SA-ASR  has been engineered to also run 300 Norma and 338 Norma calibers reliably and accurately suppressed and unsuppressed. Utilizing our Quick Change Upper Receiver Assemblies, the end-user can quickly, easily, and without tools change between calibers. The concept behind development of the MK-18 was to provide U.S. troops with a lightweight semi-auto platform suitable for extreme distance accuracy.  While also providing system capable of rapid multi-target engagements and anti-material applications. Utilizing a rifle design familiar to U.S. troops while chambering it in 338LM and 300NM gives end-users an overmatched capability in a semi-auto platform, that can be jumped, roped or patrolled with ease.