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Author Topic: barrel twist, calibre  (Read 928 times)

Offline greggholmes

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barrel twist, calibre
« on: April 05, 2016, 08:30:51 PM »
I ordered a replacement barrel for my tc hawkens off ebay that I'm going to have rebored to shoot slugs. Its a 15/16s .45. I'm looking for recommendations for caliber and twist.
I'm making a "flint slug gun".
I'd like opinions.
Thanks
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Skagit Muzzle loaders
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Any arm save our mothers', that arm is Brown Bess!


Offline Uncle Russ

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Re: barrel twist, calibre
« Reply #1 on: April 05, 2016, 09:02:00 PM »
Quote from: "greggholmes"
I ordered a replacement barrel for my tc hawkens off ebay that I'm going to have rebored to shoot slugs. Its a 15/16s .45. I'm looking for recommendations for caliber and twist.
I'm making a "flint slug gun".
I'd like opinions.
Thanks

Sounds like fun!
I have one Green Mountain "fast twist" barrel in .50 that is 1:26, if I remember correctly.
It does fairly well out to 100 yds, but I often wish it was a bit faster.

In  .45 caliber I would think you might want it a wee bit bit faster...perhaps even 1:18 or 1:20.
That is just my thinking and I have nothing handy to support those thoughts, just experience.
The Greenhill formula has been around for ages, many swear by it, while just as many swear at it.  

http://kwk.us/twist.html

At one time I had a much more simple formula to help in such matters,  but I can't seem to find it in my bookmarks.
The "preferred" rate of twist is always in relation to the diameter, and length, of the projectile for best performance at any given distance....when it comes to Long Range Muzzleloaders, that relationship seems to be a bit flexible based on a given propellant and the amount of that propellant.

Uncle Russ...
It's the many things we don't do that totally sets us apart.
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Offline dbm

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Re: barrel twist, calibre
« Reply #2 on: May 01, 2016, 04:36:10 AM »
For .45 call, 1 in 18 is the twist most commonly used today, although some have been moving to 1 in 16. The 19th Century British long range match rifles were most commonly 1:18 - 1:20.

I don't know what sort of weight bullets you're planning on trying, but be sure your breech plug is up to the job. Also, match rifles are commonly fitted with platinum lined nipples as otherwise they burn out quickly. This may be an issue with your touch hole if you're shooting flint.

David
« Last Edit: May 01, 2016, 01:15:41 PM by dbm »
David Minshall - www.researchpress.co.uk ~ www.facebook.com/ResearchPress
Firearms, Long Range Target Shooting & Associated History

Offline greggholmes

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Re: barrel twist, calibre
« Reply #3 on: May 01, 2016, 07:31:51 AM »
thanks for all the input, got a good deal on the barrel so im going to try something diferent
Member #675
Skagit Muzzle loaders
Expires June16, 2017

Any arm save our mothers', that arm is Brown Bess!