Hi all today I went to a local gun shop (bad idea for me)and they had a used sidelock labeled Jonathon Browning .50 cal Mountain Rifle it shows a lot of use but not abuse, bore is clean and not rusted the nipple area shows no rust.It has a single trigger, adjustable rear sight and brass hardware, my questions are who manufactured these (my first thought was Lyman) and if anyone knows what the rate of twist is I didn't think to measure it,The asking price is 350.00 it shows wear the stock could be refinished but I kind of like the used look.any info or opinions would be helpfull thanks.

The Jonathan Browning Mountain Rifles from all I read on them were great shooting well made rifles. As for barrel twists;

The JBMR's have the following rifling twist.

45 caliber......1-54"

50 caliber......1-60"

54 caliber......1-62"

the usual price you see being asked for them ranges from $350-$500 on the auction sites.

In good shape, those rifles are usually considerably higher priced. If you do a google search for "Browning Mountain Rifle" including the quotes - you'll quickly see his asking is fairly reasonable depending upon condition.

Thanks this is what I wanted to find out I wanted a rifle for shooting round ball and this may be it.

That should be an excellent shooting roundball rifle. I'd get some .018 thick patch like pillow tick, and a .490 ball for a tight fit, and that should drill holes out there... good luck. If you get it, be sure and post a picture.

well I missed it. things got messed up at work this morning so I went down at lunch time and it sold less than half an hour before I got there.

He who hesitates is lost. Better luck with the next rifle...

I can't say who made the Mountain Rifle. It was NOT Lyman! Lyman does NOT make ANY guns. They merely import them. Usually from Spain & Italy. But at the time Browning was selling those rifles, they were having a number of their rifles made in Japan. Probably still are. That rifle MIGHT have been made by B.C. Miroku. If so, it is of higher quality than most of the Spanish ones, and probably as good as those of Italian origin.....

I have one 50 and 54 cal.two barrels.Great shape.

I have a iron mounted Browning Mountain Rifle that was originally a .50, but i had it bored out by Bobby Hoyt to slow twist .58. The BMR has a single set trigger, one of the few production guns to have one. You push the trigger forward to set it.