http://www.patreon.com/ForgottenWeapons The German firm Heckler & Koch spent several decades building firearms all based on the same basic operating system: roller-delayed blowback (often called roller-locked, although they are not technically locked breech actions). The two best known worldwide are most likely the model 91 (aka the G3, in German Army service) and the MP-5. However, H&K also released a sporterized version of the HK-91 in an attempt to break into different aspects of the civilian firearms market. In fact, they made two sporting version, and these today are the SL-6 and SL-7, which were more or less "paramilitary" rifles chambered for the 5.56mm and 7.62mm NATO cartridges respectively. They feature a mix of civilian and military features...on the civilian side, they have small capacity magazines (3- and 10-round), sporting-style wooden stocks, and very nice triggers. On the military side, the retain the sling attachments and iron sights of the HK-91. Despite being relatively unknown in the US (where they were not available for very long, and also rather expensive), these H&K products are of excellent quality, and you will rarely find owners who are not very happy with them.