15/16" vs 1" .54 Green Mountain barrel and Green Mountain vs Colerain Barrels

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lonewolf172

40 Cal
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Hi all. First. Just got an email from Doug at Pecatoinia Rivers about their Underhammer kit and what's available right now. They don't have any 1X36" Green Mountain (GM) in .54 cal barrels in stock and he said that GM won't be making any ML barrels in that configuration for at least 2 months. He does have a 15/16X36" GM barrel in .54 in stock OR a 3/4"x 16" Colerain in .54 cal. Never heard of Colerain. Is the 15/16 GM barrel just as strong and accurate compared to the 1" barrel and what about the Colerain? I really like the 1 in 70" twist in the GM barrels compared to the 1 in 56" in the Colerain. So I need some expert advise and opinions.
 
Colerain has been making high quality barrels for years. They are among the best available. The only negative I have to say about them is the outside of the barrel needs to be draw filed to remove some of the machining marks on them.

I don't know what you plan to do with your rifle but IMO, a 1" octagon barrel is too heavy for doing anything beyond target shooting off a bench or over a log.
The 15/16" barrel will be about 1 pound lighter and with a 36" long barrel, that will make a noticeable difference in how "muzzle heavy" the rifle will feel.
 
Colerain has been making high quality barrels for years. They are among the best available. The only negative I have to say about them is the outside of the barrel needs to be draw filed to remove some of the machining marks on them.

I don't know what you plan to do with your rifle but IMO, a 1" octagon barrel is too heavy for doing anything beyond target shooting off a bench or over a log.
The 15/16" barrel will be about 1 pound lighter and with a 36" long barrel, that will make a noticeable difference in how "muzzle heavy" the rifle will feel.
Do you see any difference in strength and accuracy in going with the 15/16" Green Mountain barrel over the 1" barrel? I'd rather stay with the Green Mountain barrel mainly because of the 1 in 70 twist. can you PM me?
 
I promise last post asking for advise and opinion on this subject. I have 2 chooses in barrels for my Underhammer build from the kit by Pecatonica Rifle. I'll be using the Underhammer for both target and deer hunting here in Indiana. Target shooting from a bench and hunting from log or cross sticks so really not worried about weight. Prefer using patched round ball with Triple7 in FF or FFF powder with
70-90gr. Here are my barrel options:
1) 15/16X36" .54 cal Green Mountain full octagon barrel with a 1-70" twist
2) 1X36" .54 cal Colerain full octagon barrel with a 1-56 twist
My other option would be to totally change calibers and go to a .50 but I have to see if Pecatonica has a 1X36" Green Mountain barrel in .50cal. YEs I do prefer the Green Mountain barrel s mainly because of the slower twist. Looking at ballistics between a .50 and .54 at say 50yds using 90gr FFF GOEX there isn't much difference and both would probably take down the size of deers we have here in Indiana. The ballistics are:
So there you have it, sorry this post is so long. let me hear your advise and opinions please.
 
For target shooting, I would go with the stiffer 1" barrel. The 1 in 56 twist will give excellent accuracy with less powder than the 1 in 70 twist and also be effective on deer sized game. Just my opinion.
 
For target shooting, I would go with the stiffer 1" barrel. The 1 in 56 twist will give excellent accuracy with less powder than the 1 in 70 twist and also be effective on deer sized game. Just my opinion.

Yes Mike has a point to consider, fur sur.... ;)

(I have both Colerain and GM straight barrels in rifles and I like them both..., so can't say one brand is better than the other)

To Mike's point, the prevailing thought is that while the slow twist is great for a round ball and heavy loads, they tend to need heavy loads. Now of course this can vary and might not apply to a 1:70 twist, GM barrel that you get, but..., the 1:56 twist rate has a chance to shoot better with a light "plinking" load, at least that's a prevailing thought.

The weight difference between the two will not be a factor.

A further thought. So say you get the Colerain which is the thicker barrel, and after a time you decide you want something different. IF you want a smooth bore to do both shot and ball you're fine with either barrel being reamed smooth BUT if you decided you wanted a rifled .58..., I think you'd be only able to get that done in the thicker, Colerain barrel.

LD
 
For target shooting, I would go with the stiffer 1" barrel. The 1 in 56 twist will give excellent accuracy with less powder than the 1 in 70 twist and also be effective on deer sized game. Just my opinion.
Hi. I assume you're referring to the Colerain barrel. I really don't know anything about them. Are the good barrels?
 
I have a GM with 1:70 ROT and a Colerain with 1:56 ROT. They are 40" long and 54 cal. I like the GM more. It is less picky with loads. I can shoot a long string without swabbing and the POI doesn't move. With the Colerain, after 3 shots the POI starts moving if I don't swab really good. When clean, the GM seems to take less effort and a lot less patches before they come out clean. The Colerain barrel is a bit tighter, and if I shoot 3 without swabbing, the fourth needs to be really pounded in. The GM with the same components will load 15 or more without swabbing without much noticeable increase in loading pressure, certainly not to the point of pounding. They are both good barrels and serve the stock and action they are on well. My Colerain is swamped and much lighter than the GM. Overall though, I prefer the GM.
 
The Colerain barrels are very good barrels. That's an observation, not an opinion. I have a Colerain barrel in my Harper's Ferry 1803. Mine has round roove rifling.

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It's just my opinion but, there should be no difference in accuracy or strength between the two barrel sizes. Regardless of which barrel you choose, you are going to have to do a lot of shooting to find the best, most accurate combination of powder type, powder load, ball size, patch thickness and patch lube for your gun.

By the way, Green Mountain data says a 15/16" octagon X 36" long barrel in .54 caliber weighs 4.93 pounds. In a 1" octagon, the 36", .54 caliber barrel weighs 5.95 pounds.

I don't know that I can add anything via a PM that I couldn't say here.
 
I have a GM with 1:70 ROT and a Colerain with 1:56 ROT. They are 40" long and 54 cal. I like the GM more. It is less picky with loads. I can shoot a long string without swabbing and the POI doesn't move. With the Colerain, after 3 shots the POI starts moving if I don't swab really good. When clean, the GM seems to take less effort and a lot less patches before they come out clean. The Colerain barrel is a bit tighter, and if I shoot 3 without swabbing, the fourth needs to be really pounded in. The GM with the same components will load 15 or more without swabbing without much noticeable increase in loading pressure, certainly not to the point of pounding. They are both good barrels and serve the stock and action they are on well. My Colerain is swamped and much lighter than the GM. Overall though, I prefer the GM.
Thanks. That's the kind of information I'm looking for. Instead of the .54 I may go with a .50 1X36" green mountain full octagon barrel. Heard from Doug at Pecatonia Rifle and he has one in stock After looking at the ballistics for the 2 different calibers there's not that much difference plus I get the GM barrel I want. Just thinking if I should have it cut 2-4", a little less weight, and recrowned. What do you think? Here's the ballistics I found, even though they were with FFF GOEX. I'd go with Triple& and just reduce load by say 15%.

>50 Cal.
Load Muzzle Velocity/Muzzle Energy 50-Yard Velocity/Energy 100-Yard Velocity/Energy
90 gr. 1,754 f.p.s./1,571 f.p.e. 1,369 f.p.s./957 f.p.e. 1,066 f.p.s./583 f.p.e.
100 gr. 1,837 f.p.s./1,723 f.p.e. 1,411 f.p.s./1,016 f.p.e. 1,101 f.p.s./617 f.p.e.

.54 Cal
Load Muzzle Velocity/Muzzle Energy 50-Yard Velocity/Energy 100-Yard Velocity/Energy
90 gr. 1,754 f.p.s./1,571 f.p.e. 1,369 f.p.s./957 f.p.e. 1,066 f.p.s./583 f.p.e.
100 gr. 1,837 f.p.s./1,723 f.p.e. 1,411 f.p.s./1,016 f.p.e. 1,101 f.p.s./617 f.p.e.
 
It's just my opinion but, there should be no difference in accuracy or strength between the two barrel sizes. Regardless of which barrel you choose, you are going to have to do a lot of shooting to find the best, most accurate combination of powder type, powder load, ball size, patch thickness and patch lube for your gun.

By the way, Green Mountain data says a 15/16" octagon X 36" long barrel in .54 caliber weighs 4.93 pounds. In a 1" octagon, the 36", .54 caliber barrel weighs 5.95 pounds.

I don't know that I can add anything via a PM that I couldn't say here.
Thanks. Great info
 
Thanks. That's the kind of information I'm looking for. Instead of the .54 I may go with a .50 1X36" green mountain full octagon barrel. Heard from Doug at Pecatonia Rifle and he has one in stock After looking at the ballistics for the 2 different calibers there's not that much difference plus I get the GM barrel I want. Just thinking if I should have it cut 2-4", a little less weight, and recrowned. What do you think? Here's the ballistics I found, even though they were with FFF GOEX. I'd go with Triple& and just reduce load by say 15%.

>50 Cal.
Load Muzzle Velocity/Muzzle Energy 50-Yard Velocity/Energy 100-Yard Velocity/Energy
90 gr. 2,011 f.p.s./1,643 f.p.e. 1,493 f.p.e./905 f.p.e. 1,139 f.p.s./525 f.p.e.
100 gr. 2,092 f.p.s./1,779 f.p.e. 1,552 f.p.s./978 f.p.e. 1,171 f.p.s./573 f.p.e.


.54 Cal
Load Muzzle Velocity/Muzzle Energy 50-Yard Velocity/Energy 100-Yard Velocity/Energy
90 gr. 1,754 f.p.s./1,571 f.p.e. 1,369 f.p.s./957 f.p.e. 1,066 f.p.s./583 f.p.e.
100 gr. 1,837 f.p.s./1,723 f.p.e. 1,411 f.p.s./1,016 f.p.e. 1,101 f.p.s./617 f.p.e.
Sorry I just realized that both ballistics shown are the same. Here's corrections if anyones is interested. Both at 50yds still adequate for taking deer.
 
The 54 barrel in the same size is usually lighter due to the bigger hole compared to the 50. I like the heavier ball of the 54 because I want to have good odds of an exit, and weight and size advantage if I hit a shoulder or spine. Personal preference of course, it’s a tough choice
 
I have built many plains type of rifles using GM 15/16" barrels in .50 and .54 calibers. They are great barrels and I find that the 15/16" .54 caliber X 34" barrel is a joy to shoot and carry for a hunter and as a target rifle. What ever brand you choose either one will work for what you want it for. I would go with the .54 caliber and 15/16" GM barrel :thumb: ;):ghostly::ThankYou::horseback:.
 
I built a pair of Hawkens, both in .54
The Green Mtn is tapered 1 1/8” to 1”x 36”
The Colerain is 1”x36”.
Both are excellent and equally accurate when given at least 70 gns 2F.
The Colerain seemed to need a longer break-in period than the GM... or maybe it was breaking me in ...?...
 
We have used both Green Mountain and Colerain barrels in my shop as well as Rice and
Getz. I received one Colerain barrel with a bad crown which was replaced immediately by the manufacturer. The replacement was simply not a good barrel.
Inspection with a borescope revealed a roughly cut bore. It would not shoot good groups from a benchrest. I had to scrap it and replace it with a Rice. My GM barrels are good ones.
The borescope shows a smooth interior surface and they shoot good groups from bench . The Rice barrels are superior to all others named.
 
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