1" Barrel

[Daehenoc]

For heavy bullets and "heavy" charges what's the largest caliber most folks use in a 1" barrel? 50? 54? 58?

[dbm]

The bore on the British long range match rifle of the 1860s/70s was .45, with rifling twist 1:18-1:22 or gain twist.

What are you seeking to do: make a match rifle or something to hunt with?

David

[Daehenoc]

So, what do you think should be the max bore for a one inch barrel?

[Riley/MN]

I have a 1" .58 cal CVA Mtn rifle bbl.

Not for long-range, but for hunting (round ball).

[Daehenoc]

Are flintlock barrels stronger or weaker than a percussion set-up for the same size bore? Any difference? A threaded hole in the side of the barrel could be a liabity whether it holds a nipple or a flash hole.
But, it doesn't seem likely though that a flinter would be preferable to percussion for long range does it? Still, it might be fun to try and find out!

[dbm]

I wouldn't fancy being next to someone with a flinter set up for long range. The blow back through the flash hole when using heavy bullets and charges would lead to loss of pressure (and MV) when compared to percussion.

If you're building a long range rifle then give serious consideration to the breech plug. The link is to an article on my web site.

David

[Daehenoc]

Yes, I'd seen that article. The selection of rifles to make into a "long range" rifle (along with caliber and the loads to use) is not a subject one should approach with a cavalier attitude.  After reading the 1855 "Report Of Experiments With Small Arms For The Military Services" and in light of my age (decreasing visual capabilities), I tend to think of "long range" in terms of two or three hundred yards rather than a thousand. I will see what is out there and have a rifle built.
Hence the question, For heavy bullets and "heavy" charges what's the largest caliber most folks use in a 1" barrel?, "heavy" obviously being a relative term subject to alteration and interpretation with changes in barrels, bullets, etc.
I'm very interested in learning what others have experience with.

[dbm]

I have no experience in building rifles and cannot comment on the largest calibre for a 1" barrel. You specifically asked about " 50? 54? 58?" and I observed that .45 was the calibre used in British long range match rifles. Largest calibre won't necessarily give you best accuracy.

Here in the UK we shoot .577 Enfields out to 800 yards... that's long range, but the accuarcy doesn't compare with the .45. In Continental Europe and for the mid-range distances you refer to, .40 cal rifles are popular. These will need twists in the order of 1 in 16.

David

[Daehenoc]

A .47 bore barrel would work for paper patching the .46 molds that everyone makes for .45 rifles.

[tg]

I think that 1" barrels are used for .62 rifles and smoothbores now, I think I would want more meat at the breech if going for a gun that uses heavy charges, at some point you loose threads  for the liner or drum with larger bores in a given barrel size that has always concerned me.

[mossie]

I have a 15/16" .50 caliber that I shoot 385 and 410 grain conicals from with 90 grains of Goex 2f and it's a flinter. I do admit I wonder if I am pushing the limits; the book that came with the barrel actually recommends such loads.

I also just bought a 15/16" .54 GM barrel that I intend to make a flinter with; I was planning on a load up to 100 grains of 2f.  Seems like if the drill and taps are no more than .050 deep it should be ok.  They sell the same barrel as an IBS so I can't see any difference.

So with a .58 in a 1" I don't think I would worry about not having enough meat on the barrel if you kept load under 110 grains of 2f.

[Daehenoc]

Still haven't had a rifle specially put together but a lot of research has been plowed through, as well as a lot of shooting.
That original point being pondered on four years ago was "For heavy bullets and "heavy" charges what's the largest caliber most folks use in a 1" barrel? 50? 54? 58?"
Well, Lymans book that came with a Great Plains Rifle (15/16" barrels) says that in a .50 with a 420 grain bullet the maximum charge is 100 grains of FFg. I think that's about as much oomph as I'd care to launch out of a TC Renegade, much less an Interarms type rifle. Looking at the TC manual, it says 100 grains FFg with a 370 grain bullet. And those are not particularly built with a breech design to limit the pressure feeding back to the base of the nipple.
So, ah ha. As the guy in the white hat used to say, "Big bubble, no trouble".

I've been shooting a .40 with 16" twist for a few years and find that I mostly like honkin' 240 grainers paper patched. It will shoot heavies long and slow but mostly I just don't. I'd just as soon drift .395 round ball across the yard for fun. And I'm fixin' to try out some 250 grain plain base lubed bullets to see what happens.
But I really do want to see how accurately I can make a flintlock perform with a faster twist barrel. I'm thinking maybe a 1" barrel, .52 caliber and fast enough twist to paper patch with the 450 grain molds made by Lee and Lymans.

[Stormrider51]

Hi,
Unfortunately, your original question is one that has no set answer because there are so many variables.  What you were really asking is "How much barrel wall thickness is required to withstand heavy loadings?"  No gunsmith is going to answer that one unless he is building the rifle and has control over the quality of the parts used and how well they are fitted.  He will also need to know what you mean by "heavy" in terms of powder charges and projectile weight.  

When it comes to accuracy, whatever the distance, other factors come into play.  Barrel rigidity and heating for instance.  The thicker the barrel wall, the more rigid the barrel, and the slower it heats up/cools down (greater thermal stability).  A rifle barrel actually vibrates like a tuning fork when the gun is fired.  The heavier the barrel the less the vibration.  That's why bench rest rifles have those huge barrels.  The same goes for thermal stability.  A thick barrel will maintain a more stable temperature from shot to shot.  As a barrel heats and cools it actually changes its dimensions slightly.  It can also warp, which will change the point of bullet impact.  I believe these factors are why the .45 caliber became so popular in long range shooting.  There's nothing magical about .45 as a caliber, it's the fact that it permits good barrel wall thickness at a weight a person can carry around and shoot comfortably.

I think you can answer your own question regarding biggest caliber in a 1" barrel though.  If you haven't already done so, take a look at the offerings from various barrel makers.  I think you will find that .58 is the biggest bore offered.

Storm

[Daehenoc]

The original question was...

" For heavy bullets and "heavy" charges what's the largest caliber most folks use in a 1" barrel? "

Cut and dried. No variables. Was looking for input from people that had already seen it, been there and done got the tee shirt.
Since then I have done a lot a research and a lot of testing. Specifically on 1" barrels as that is most convenient for my purposes. As intimated above, .52 is looking pretty good for a flinter.

[Daehenoc]

The 38" long .52 barrel is being completed (rebored). Went with cap lock because I had a percussion GM "drop-in" barrel to work with.
Got the plain base 450 grain mold to paper patch. A Lyman .515 diameter mold is on the way for tight patched round ball.
Got my fingers crossed. This is an all used parts scavenger type production.
Hopefully come spring time she'll be ready to go.