Green Mountain Barrel

[shifty]

Thinking about fitting a 54cal 1/70 twist  15/16"GMB to one of my half stock  rifles ,this barrel comes 36" long ,what would be your choice to cut it to or would you cut at all.

[galamb]

You plan on fitting this to an existing stock such as a T/C or a Lyman etc???

While @ 36" it would be "long" compared to what is there now, from a more historical perspective, it wouldn't be long for the type of rifles those were supposedly patterned after/purporting to represent.

There are enough advantages to using a longer barrel (better sight plane, more efficient use of powder, a bit more velocity from the same charge) that unless the longer barrel would hinder the use of the rifle, I would leave it alone at 36".

At worst, if you don't like it - get's hung up a lot while carrying etc, you can always cut it back later.

Unless I was building a specific rifle based on an original that had a barrel sub-36", I would use a 36" barrel on any half-stock patterned after a 1840's onward design to keep it "typical" of what would have been built "back when".

[D. Taylor Sapergia]

If you decide to cut it, cut it off at the breech and re-thread for the plug.  If you cut the muzzle, you may find run-out in the bore, and the hole won't be centred in the barrel.  I'd leave it 36"...with 15/16" AF, it won't be too heavy.  Don't forget, you need a new rib too.

[WadePatton]

Don't be afraid of long.  Now that i've two seasons on toting a 42" bbl, I'm quite satisfied that it's no hindrance to my movement through the brush.  and now "modern" length stuff looks awkward and feels clubbish to me.  (I do realize that some guns correctly call for shorter bbls-but those aren't me.)

Another advantage of long is moving the report further from your eardrums-if you hunt.

Try 36", you can always chop it back later if you decide to.

[JTR]

So is a 1 in 70 twist common to a 54 caliber?

I'm familiar with 1/48 for pea shooters and 1/66 for bigger bore guns, so is 1/70 just a twist on 1/66.

John

[WadePatton]

So is a 1 in 70 twist common to a 54 caliber?

I'm familiar with 1/48 for pea shooters and 1/66 for bigger bore guns, so is 1/70 just a twist on 1/66.

John

Them fellas up in PA put a 56-inch twist in my .54-as their standard rate.  Their published normal twists are: 48 for .36 and .40, 56 for .45-.58, and 66 for .62.    http://colerainbarrel.com/rifled_barrels.html

I used to sweat those details, but have gotten over it with the PRB.  The variables are relatively limited with powder and ball, so long as the bbl maker gives me what he thinks is good for PRB/cal then I don't even need to know anymore.

[galamb]

My Green Mountain 50 cal is 1:70 as well.

Probably just their take on a round ball twist.

[JCKelly]

Rumor has it their barrels are (or were?) choke bored, another reason not to chop it off at the muzzle.
Some of you know how picky I am about the steel in anything I shoot.
Bob Elka has finished a Frederick Sell for me with a .45 cal 38" swamped Green Mountain barrel (light enough for a miserable left shoulder to lift)
All I gotta do now is finish paying for it.
Pictures in about a month.

[mountainman]

Are green mountain barrels still available?

[galamb]

Depends who you talk to.

TOTW has told some customers that they will discontinued and they have cut their offerings down to three (from 8 a few months back), but they are all currently in stock.

Green Mountain still has them available on their website (at least some barrels show "in stock").

MBS replenished some that were out of stock a few months back.

There is no listing anywhere, including the GM site for any of their swamped profiles.

It looks like the only thing out there is 45/50/54 cal offerings in 7/8, 15/16 and 1" straight profiles.


 

[shifty]

Yes that is what the GM barrel specs are  1/70 twist and the straight barrels are all i can find listen too,my 58cal Robby Hoyt has a 1/60 twist, they all work but generally it is believed the slower twist will still be accurate with heavier charges of powder , that is what i was looking at.

[moleeyes36]

Depends who you talk to.

TOTW has told some customers that they will discontinued and they have cut their offerings down to three (from 8 a few months back), but they are all currently in stock.

Green Mountain still has them available on their website (at least some barrels show "in stock").

MBS replenished some that were out of stock a few months back.

There is no listing anywhere, including the GM site for any of their swamped profiles.

It looks like the only thing out there is 45/50/54 cal offerings in 7/8, 15/16 and 1" straight profiles.


 

I called GM a few months ago because they showed their swamped barrels on their website.  I asked if they were still available and was told no and also that they had been discontinued.

Mole Eyes