Can someone tell me if the Knight barrels from a mountanieer will fit a disc extreme? I'd like to have my .50 Extreme barrel swapped out for a 1:22 twist .45 cal.

They will IF you have the more modern stock! A stock that will accept the winged recoil lug. If it is an older stock it would have to be inletted.

This is a Knight Mountaineer dropped a DISC thumbhole stock

That barrel does not appear to be fluted like a Mountaineer barrel

You are right - sorry about that it is a An Ultra Lite barrel with the same fluted recoil lug.

Here is the mountaineer in a Knight TH stock

I got a response from Knight with this response: You can order a 45 cal in a 1:20 twist which is the Knight twist rate in a Mountaineer barrel which will work in the Disc stock.. These are direct drop in barrels and the barrel and receiver are 1 piece. If you do this though, you will need to change your breech plug due to the length of the one for Disc being shorter. You will be able to use your Disc bolt handle and firing pin.
At $339 plus shipping and a different BP it would be pretty cool to have a rifle that I can switch out from .45 to .50 in a snap.
But in all honesty I'd probably only shoot the .45.

I am assuming this was Steve that sent you that response - and I believe he was right on with all of his points!

Bronko, My experience with switch barrel guns (and I've had several) is that;
(a) one barrel quickly becomes the favorite and the other one sits in the closet unused, or
(b) you soon start looking for a second stock and end up with two guns anyway.

Option "b" above is how I ended up with the Sinful Sisters.

Love the sisters on the bottom. I have the same sister on top but without the scope.

Ed, a guy can get in trouble when he loves three sisters.

The scopes are all Simmons fixed 4X ProDiamond models. Here are a 200 and a 300-yard 5-shot group with the .45 and your soft lead bullets.







Anyway, getting back to Bronko's thoughts. In comment #5 he said, "At $339 plus shipping and a different BP it would be pretty cool to have a rifle that I can switch out from .45 to .50 in a snap. But in all honesty I'd probably only shoot the .45." I think he's right and will either be looking for a second stock to have two guns, or be putting the .50 barrel up for sale.

Mike I hear you about shooting the 45. I sold my White UltraMag in 50cal because I never shot it much. Those 465gr conicals shoot great for me also. But for hunting with the range being mostly 75 yds or less my 345gr bullets work great for deer. The most accurate bullet I ever shot out of my Whites was a mold made by Accurate Molds was the 45-510M. It wasn’t mine but a fellow DWB that I did him a favor and made a batch for him and kept a few for myself.