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Browning made two versions of these muzzleloaders.
The "Jonathan Browning Mountain Rifle" had a single set trigger which is cocked by pushing it forward, a engraved lock plate and select walnut stock. It was a cased gun with a medallion and powder horn. 1000 of them were made in 1978.
The "Mountain Rifle" was a plainer version that was made starting about the same time.
Over the years as I understand it, several different manufactures were hired by Browning to make these rifles and their quality diminished during that period.
A few people have noted that these rifles "don't look like a Hawken", but they were never intended to "look like a Hawken". They were intended to look "like a Browning" and reflect the spirit of the guns made by Jonathan Browning (1805-1879) who built guns from 1825 thru 1879.
He was the father of John M. Browning who is the person usually thought of when the name Browning and guns are mentioned.
There are several of our members who own Browning Mountain Rifles and they find the guns shoot well.
The latest values I have for these guns is from the book, "Third Edition Blue Book of Modern Black Powder Values" which, being published in 2003 is out of date.
At that time the cased rifle was worth $750 and the plainer version was worth $595.