Jaeger Rifle Specs

[ejcrist]

The third rifle I'll be putting together after I finish the second one I'm working on at the moment is a TOW jaeger kit in 62. In wanting to learn more about jaeger's I ordered the Shumway book "Jaeger Rifles" and got it in the mail today. It's an outstanding reference for the various schools and I highly recommend it to anyone interested in these rifles. One thing that caught my eye was something I've read about recently and was a question I had in another post about the twist rates on the big bores. I originally wanted a 1:72 Rice barrel but ended up with a 1:66 and was a little concerned it might be too fast for hunting. After skimming through the Jaeger Rifles book I'm convinced 1:66 will be just fine. Some of the original rifles did in fact have relatively fast twists compared to today's standars. One rifle in the book on pages 36-39 made by Joseph Fruhwirth of Vienna around 1710 (58 caliber) had a 1:27 twist. Quite a few rifles in the book had very fast twists that I thought would be way too fast to shoot accurately, but I'm sure the gunsmiths back then wouldn't have been masters in their craft if the rifles they made for aristocrats didn't shoot well. So I guess I have to re-think my opinions on slow twist rates for the big bores. I just thought this subject was very interesting and wanted to share the info.

Gene 

[jerrywh]

 I have read that jaegers were loaded without patches. The bullet was pounded down the bore with a mallet.  I don't think they used very heavy charges in them.  Most of their hunting was close range.

[Stophel]

That's a myth.  They used patches.  

I have a German rifle from about 1830 and a Massachusetts rifle from around 1810-1830.  Both of them have twists of one turn in around 32" or so (something like that, it's been a while since I looked).  The German rifle is SHORT, with a 16" barrel and around .65 caliber.  The Mass. rifle barrel is 41", I think, and about .58 caliber.  I don't have access to any other rifles, but my expectation would be to find a great many "fast" twist old American rifle barrels.  

While the book is useful, I have found some of the information given by Shumway to be incorrect, but he admitted himself that he was treading on unfamiliar ground.

[kaintuck]

Any twist can shoot....you just have to tinker with the amount of powder for that given rifle.....
Then there's the thickness of patch......

Marc n tomtom

[Mike Brooks]

 of the original jeagers I have seen and knew what the twist was they were always one turn in the length of the barrel. So, if the gun had a 28" barrel it had a 1 in 28 twist.They must have loaded them far different than we do.

[Acer Saccharum]

They drank a lot of beer, and then got loaded.

[Acer Saccharum]

I can't imagine loading up a fast twist with a lot of powder. Maybe this allowed less powder to be used for short range shooting? Would these short barreled guns be much good beyond 50 yards?

[Long John]

The understandings regarding how black powder burns inside the rifle barrel was developed in the late 1800's.  The Jaeger rifles were made without knowing the physical chemistry that enables us to now optimize twist and rifling form to bore size.

Black powder burns most efficiently at a pressure of approximately 10,000 PSI.  To optimize your barrel you need to develop a load that achieves and maintains that pressure for the entire time the bullet is traveling down the barrel.  This can be facilitated by slowing down the twist as bore diameter increases, all other variable held constant.

My 54 caliber rifle has a 72 inch twist and shoots an 85 grain load of FFFg very nicely.  I would expect a 62 caliber rifle with its heavier ball would do best with a slow twist.  I imagine that a rifle of that bore with a faster twist the charge will have to be reduced to prevent excessive fouling.  Every rifle has an ideal load for what you plan to do with it.  Finding that ideal load is part of the load development process.

Best Regards,

John Cholin

[Gaeckle]

of the original jeagers I have seen and knew what the twist was they were always one turn in the length of the barrel. So, if the gun had a 28" barrel it had a 1 in 28 twist.They must have loaded them far different than we do.

I think a barrel maker of old would have just one twist lead for their rifling bench. So would that dictate, for instance, that the barrel maker if all he had was a 1 in 28 inch twist lead would he only be able to make a 28 inch barrel? All the old barrels I have have a twist in the area of 1 in 60 inches, despite the caliber. I've always wondered if the old timey guy with a rifling bench had more than one lead for different twist, but I have a tendency to to believe that the old smiths had just one. Makes me wonder if those European guys rifled at a faster twist.

[jerrywh]

 The German gunmakers of old were a lot smarter than some of us today think they were.  These large bore guns were intentionally made for short range light load shooting in my opinion. Another hint is the fact that they had short barrels.  It doesn't do much good to put a large powder charge in a short barrel. I also suspect that all their powder for sporting arms was the same granulation. Today we use different granulations for various reasons.
  I also believe that almost all their hunting was at very close range and accuracy was their prime concern. Their is no advantage to a 120 grain charge in a 28" barrel for a forty yard shot. The hunters of the day also carried swords.  If you look in some of the books on hunting of the period you will see scenes of people shooting from a balcony of sort and the game was run past the shooters with dogs and game runners. This may not have been the norm but it did happen that way.  Most of the game then was owned by aristocrats as was most all of the land. It wasn't anything like we have today and the guns reflected the conditions to a large extent.

[Daryl]

Forsyth had a 13 bore (.705") that stripped if he 'gave' it more than 1 3/4 drams of powder.  It had a 13' trajectory over 100yards and was useless for shooting game due to that twist and ball arc.

1 3/4 drams is only 48gr. of powder.

His own written word was Drachms, however that would be, if in apothecaries weight, 1 3/4 x 60 = 105gr.  which would reduce the 100yard trajectory to only about 4 1/2 or 5 inches.

1 3/4 drams would indeed give very close to his 13" trajectory - thus again, his use of Drachms is incorrect - as he was clearly speaking of drams.

Big bores, tiny charges, wounded game - hounds catch the wounded game which is then 'brought to bag'. Everyone but the deer has fun - for that time.

[hanshi]

From what I've experienced/discovered/researched, generally all black sporting powder is burned in barrel lengths of 28" to 30" and velocity gains beyond that length are minimal.  Barrels of 20" can produce 90% plus the velocity of a 40" barrel.  A chronograph I purchased 20 years ago truly opened my eyes to reality vs expectation.  Jeagers, as I understand the breed, are typically "short?" barreled.  I have seen pictures of old jeagers with barrels longer than that but nothing like the 42" to 48" American longrifles.

Even a fast twist barrel can accurately handle solid powder charges given deep enough rifling and a good patch.  A large ball requires less velocity to attain lethality than a small one does.  Range and drop are another matter entirely, as is barrel individuality.     

[Mike Brooks]

of the original jeagers I have seen and knew what the twist was they were always one turn in the length of the barrel. So, if the gun had a 28" barrel it had a 1 in 28 twist.They must have loaded them far different than we do.

I think a barrel maker of old would have just one twist lead for their rifling bench. So would that dictate, for instance, that the barrel maker if all he had was a 1 in 28 inch twist lead would he only be able to make a 28 inch barrel? All the old barrels I have have a twist in the area of 1 in 60 inches, despite the caliber. I've always wondered if the old timey guy with a rifling bench had more than one lead for different twist, but I have a tendency to to believe that the old smiths had just one. Makes me wonder if those European guys rifled at a faster twist.

Only reporting what I have personally observed on 18th century German hunting rifles. What was going on in colonial America may have been quite different.

[Stophel]

Rifling grooves tended to be DEEP, too.  Sometimes rather deeper than what you see today.  I would suspect that has something to do with it.  

Both my old rifles (again, one German, one American) have bores so wore out and beat up, you can't really measure anything, but even heavily worn, the grooves are still as deep or more as, say, on a Colerain barrel.  On the Massachusetts rifle, ONE groove has a decent looking spot near the muzzle where it's still relatively deep and crisp (square grooves... actually the others appear round, they are so worn out!) and it appears nearly twice as deep as a Green Mountain rifling groove.  Other old rifles I have seen have shown similarly deep grooves.

[Stophel]

Now, realize that the grooves are individually "crowned", so they have a deeper appearance at the muzzle, but you can still see inside the bore they're fairly deep grooves.


A 19th century restock of a mid 18th century German rifle:
 
Again, the grooves are "crowned" on this rifle just a little bit, so the grooves are not actually quite as deep as they appear on the muzzle, but looking past the crown, into the bore you can see that the grooves are still quite cavernous.

[Acer Saccharum]

Crowning the grooves forces the patch to collect in the grooves as you push the ball into the bore. Maybe that helps fill the cavernous grooves.

[Stophel]

Has anyone today actually TRIED shooting a "fast twist" barrel to see what it actually does?  Or are we all just trusting "common wisdom"?

[Stophel]

Well, here's something:

http://www.ctmuzzleloaders.com/antique_guns/jaeger/jaeger.html

[ejcrist]

Thanks for all the info Stophel, that was really interesting. 

[jerrywh]

Hanshi.
 In General I agree with all you said As far as modern black powder is concerned. But the powder of 1700 or 1750 was not Goex.

Those fast twist barrels shoot very well with say 50 or 60 grain charges. Also remember a lot of Jaeger rifles had two bladed sights. They were probably sighted in for 50 and 100 yds. That would compensate for the drop.
as long as a 60 caliber ball is in the air it can kill.

[hammer]

Some similarities to the English deer rifle.   Shot from a stand up in a tree in a deer park.   Looking out over the open rides through the woods.   Large calibre for knockdown.    The heavy ball losses less of its power over distance compared to a light ball.   Some of these rifles also had a coned muzzle to aid quick loading.
 
I have assumed the particularly short barrel of the Jaeger was for improved handling in close country.  As with a 26 inch double barrelled 'covet' shotgun?

[Bob Roller]

Now, realize that the grooves are individually "crowned", so they have a deeper appearance at the muzzle, but you can still see inside the bore they're fairly deep grooves.


A 19th century restock of a mid 18th century German rifle:
 
Again, the grooves are "crowned" on this rifle just a little bit, so the grooves are not actually quite as deep as they appear on the muzzle, but looking past the crown, into the bore you can see that the grooves are still quite cavernous.

I think it's called an optical confusion.Looks good no matter what the name.

Bob Roller

[lexington1]

I measured three barrels I have on 18th c. German guns. They all have really deep rifling. I really doubt that they were loaded by hammering down a bare ball with a mallet. I've read that account numerous times but I would think that deep rifling  would be hard to fill with a naked ball. If they loaded like that they would need a mallet (or sledgehammer) to load it after the first shot. Every Jaeger I've seen has had a wooden ramrod, so I would think that they were not loaded too tightly. I do wonder what type of patching was used?

Of the three Jaegers I have one has a 25" barrel and has about a 1/35" twist. One has a 28" barrel and has straight rifling, and one has about a 31" barrel and has about a 1/40" twist.

Probably not much useful information, but there it is.....

[Stophel]

I think that for rifles, either German or American, the general rule was smaller balls, thicker patches.  This, of course, gives you more leeway in the choice of patching material, but the thicker patching would be able to cram tightly into the deep grooves.   Think about it.  They couldn't go to the fabric store with a micrometer and measure their pillow ticking, looking for exactly .018" thick fabric. Smaller balls and thicker patches means you can use more varying thickness of fabric (or leather), and even if one was looser than the other, it would at least still fill the grooves and be usable.  With the thick patches, I doubt that "stripping the grooves" was a problem.  I would bet that these deep grooves and thick patches are the key to accuracy with faster twists.

Your 1 in 35" and 1 in 40" guns show that not all the rifle twists were the fast 1 in 24".  That's similar to my two guns, which are in the 32-36" range.... I'll have to measure them again, but my memory, such as it is, tells me they were about that.

[jerrywh]

 you cannot shoot a heavy load in a fast twist barrel. Therefore they were made for lighter loads. Even with sharps rifle and a 500 grn. bullet if you exceed about 1350 fps. your accuracy goes to pot. Round balls are even worse.