Looks like you have a half stock Hawken by Sharon Rifle Barrel Co. These were primarily sold as kits, which Sharon Rifle Barrel Co. introduced in 1976.
Since your rifle was likely assembled from a kit, and without some kind of makers mark, it's very unlikely to know the individual that assembled it.
Sharon sold a number of these kits before they went bankrupt in July 1978. A retail outlet called Old West Arms in Denver, CO may have purchased the remaining inventory of Sharon kits as they advertised and sold the kits for a couple years beginning in 1979.
Besides the markings on the barrel in your photograph, Sharon Hawken rifles are easily identified by the unique shape of the snail on the breech.
Sharon used L&R locks and triggers, but many of the other parts were their own design and manufacture. The lower entry pipe is also unique, but you can't tell the difference with it in place. The half stock kit came with a bar of pewter-like metal to cast the nose cap.
Sharon Rifle Barrel Co. made black powder barrels for a number of years prior to offering the kits, and they earned a good reputation for accuracy.
Phil