Here is some of the information I have found on Sharon Rifle Barrel Co. and the successors to Green River Rifle Works in old muzzleloading magazines of the period.
Sharon Rifle Barrel Co. began producing quality muzzleloader barrels around 1974 and started making Hawken kits in 1976. Sharon offered a half stock and a full stock Hawken along with a smooth bore English fowling piece and a less common trade rifle. Sharon's Hawken kits were well received in the marketplace, helped by the positive reputation their barrels had established. The company ran into financial trouble and closed in 1978.
The Sharon barrel making equipment was sold to Hayden-Holmes in Colorado Springs, Colorado. It didn't last very long, and the equipment went either to California or Oregon.
Sharon's impact in the market is disproportionate to their time on the market. Their actual production run was less than two years with enough Hawken kit inventory built up at the time of bankruptcy that another company, Old West Arms of Lakewood, CO, was able to continue sales post-bankruptcy for another year or so.
Green River Rifle Works went bankrupt in the fall of 1980. Efforts to reorganize the company and bring it out of bankruptcy failed, and the barrel making equipment was sold to a Hamilton in Duchesne, Utah who formed a company called Green River Company. That company only lasted about a year, and the barrel making equipment was sold again.
It was moved to Grand Junction, CO and a new company called Green River Barrel Co. was formed. It operated there for a few years. The company may have been sold again. In any event, it was moved to Las Vegas, NV and operated there under the same name until about 1990. During the mid-1980's, TOTW sold Green River Barrel Co. barrels.
I visited with Doc White last May while on a trip to Roosevelt, Utah and asked him about the Australian company and where the barrel making equipment ended up. He said the Australian Green River Rifle Works started using the company name without his permission and has no connection to the old company in Roosevelt. Since he hadn't registered the name or trade mark in Australia, there wasn't much he could do about their use of the name. None of the old GRRW barrel making equipment went to Australia. On one of his trips to Las Vegas a couple years ago, he went by the location where the old equipment had been used. He said that the building had new security set up around it, and the equipment was being used to make .50 caliber machine gun barrels again. Since that was what it was originally designed and set up for, it has come full circle.
Phil Meek