Ball size

[mikeinpa]

I picked up a 19th century German percussion rifle made by J Adam Kuchenreuther this week. What would be the correct size ball and patch for a bore that measures .540 across the groves and . 524 across the lands?

Thanks,

Mike

 

[TDM]

.530 ball would work.

 

[ord sgt]

More pictures of your new purchase.

 

[Spillikins]

.530 ball would work.

I think you may have misread the OP.
A good starting point for a ball would be 0.010 less than the land-to-land measurement, would it not? With a 0.012 to 0.015 patch.
Thus .514 or as close as the OP can find.

 

[Grenadier1758]

@TDM, that 0.530 ball would have to be bare balled over a wad as the ball will have to engrave on the lands as it is loaded. After all it is 0.006" over the land to land diameter.

I would start with the old tried and true ball that is 0.010" under the land to land diameter, in this application 0.514". This is not a common ball size, so either a custom mold or something close to that size. The grooves are ((0.540-0.524)/2) 0.008" so, my first recommendation is 0.015 that with reasonable compression will fit. A smaller ball should have a thicker patch, perhaps a 0.500 ball and a 0.025 canvas patch.

@Spillikins has good advice.

 

[TDM]

I think you may have misread the OP.
A good starting point for a ball would be 0.010 less than the land-to-land measurement, would it not? With a 0.012 to 0.015 patch.
Thus .514 or as close as the OP can find.

@TDM, that 0.530 ball would have to be bare balled over a wad as the ball will have to engrave on the lands as it is loaded. After all it is 0.006" over the land to land diameter.

I would start with the old tried and true ball that is 0.010" under the land to land diameter, in this application 0.514". This is not a common ball size, so either a custom mold or something close to that size. The grooves are ((0.540-0.524)/2) 0.008" so, my first recommendation is 0.015 that with reasonable compression will fit. A smaller ball should have a thicker patch, perhaps a 0.500 ball and a 0.025 canvas patch.

@Spillikins has good advice.

Yes, yes, I agree. I just read through the OP comment to quickly.

 

[Uncle Miltie]

The shop of I. Adam Kuchenreuter in Regensburg Bavaria turned out some of the best target pistols in the world, and I'm sure their rifles weren't far off. I would try a .515 ball ( 13mm) and. 015 patch. Lee makes a mold. The Log Cabin Shop sells cast round ball in a .500 or .520. Would like to see more photos of your rifle!

 

[mikeinpa]

Thanks guys, I just ordered a lee .515 mold from Track. I'll get some more pictures out today.

Mike

 

[mikeinpa]

Some pictures.

 

[Relic shooter]

Very nice Jaeger, I'm betting you will enjoy the light weigh & accuracy when matched with the right load setup !!

It's typical for muzzles on vintage Jaegers with this style of rifling to be funneled for easier loading without a short starter.
I would recommend that you drop a length of slightly smaller diameter brass rod down the barrel & pound a larger diameter round ball down 6-8" down past the muzzle so you can accurately determine measurements on the bore & rifling depths.
While rocking the barrel back & forth the brass rod will serve to fully seat the ball into the bore as it's being pushed out.

Most Jaegers I've owned & shot typically have rifling .012- .018 deep. To get optimum accuracy with minimal fouling they require a compressed lubed patch & ball combo that completely fills the lands along with the proper ball dia.
Note; to be safe, get best performance & protect your investment I highly recommend that you install a new quality nipple like Treso before firing, these nipples will provide a lifetime of top notch performance if not abused.
Relic shooter

 

[mikeinpa]

Relic shooter,

Thanks for the great info. Just so I understand you correctly, I drop a piece of brass before the ball is jammed in, then the brass works like a ram to get the ball out? It looks like the nipple threads are 7.75 mm. I think Track has those.

Mike

 

[Uncle Miltie]

Very nice Jaeger, I'm betting you will enjoy the light weigh & accuracy when matched with the right load setup !!

It's typical for muzzles on vintage Jaegers with this style of rifling to be funneled for easier loading without a short starter.
I would recommend that you drop a length of slightly smaller diameter brass rod down the barrel & pound a larger diameter round ball down 6-8" down past the muzzle so you can accurately determine measurements on the bore & rifling depths.
While rocking the barrel back & forth the brass rod will serve to fully seat the ball into the bore as it's being pushed out.

Most Jaegers I've owned & shot typically have rifling .012- .018 deep. To get optimum accuracy with minimal fouling they require a compressed lubed patch & ball combo that completely fills the lands along with the proper ball dia.
Note; to be safe, get best performance & protect your investment I highly recommend that you install a new quality nipple like Treso before firing, these nipples will provide a lifetime of top notch performance if not abused.
Relic shooter

It's not a Jaeger, it's a target rifle.

 

[Relic shooter]

Relic shooter,

Thanks for the great info. Just so I understand you correctly, I drop a piece of brass before the ball is jammed in, then the brass works like a ram to get the ball out? It looks like the nipple threads are 7.75 mm. I think Track has those.

Mike

Correct on use of the piece of brass rod
As for the nipple threads it can be iffy getting threads on a modern mfg. nipple to fit hand cut vintage threads properly but occasionally I've gotten lucky.
If the new nipple isn't a tight fit but if the outside diameter of the nipple treads are a tight fit you might be able to chase the threads with a 7.75mm tap & get that to work. Treso makes a wide variety of nipple thread sizes so won't be a problem coming up with a safe & reliable fit.

You may already have experience with what I state below, if so just ignore.

If your original nipple is corroded & frozen solid, soak the bottom 2" of the breech in a 50/50 mixture of auto transmission fluid & acetone overnight & that should do the trick, is the method I've successfully used for years. With real hard cases you may need to apply heat to the breech plug around the nipple.
On really stuck nipples I often use automotive ignition wrenches in metric or American sizes or cut a slot in a 1/4" drive socket to get the best fit as some nipple wrenches don't hold up well.
Once you have your barrel slug measurements taken I'll do my best to make a RB mold size recommendation. The original Jaegers I've rifles owned & shot all had deep rifling & required cotton pillow ticking with a high thread count to shoot the best groups. Likely won't find patches' on a dealers shelf, but take your micrometer to the fabric store & get a couple yards of the compressed thickness material you require & punch them out with an Arch punch on a hard wood or nylon surface after washing a couple times to get the sizing out.

Patch tip; I place stacks 50-75 patches & run a piece of nylon thread through the center with a needle to hang from my hunting bag. A knot at the bottom will prevent lost patches & allow for fast loading.
Happy trails !
Relic shooter

 

[mikeinpa]

You are a great help. Thanks again. I did get the nipple out after an overnight soak with Kroloil. I'll slug the barrel tomorrow.

Thanks,
Mike

 

[mikeinpa]

Correct on use of the piece of brass rod
As for the nipple threads it can be iffy getting threads on a modern mfg. nipple to fit hand cut vintage threads properly but occasionally I've gotten lucky.
If the new nipple isn't a tight fit but if the outside diameter of the nipple treads are a tight fit you might be able to chase the threads with a 7.75mm tap & get that to work. Treso makes a wide variety of nipple thread sizes so won't be a problem coming up with a safe & reliable fit.

You may already have experience with what I state below, if so just ignore.

If your original nipple is corroded & frozen solid, soak the bottom 2" of the breech in a 50/50 mixture of auto transmission fluid & acetone overnight & that should do the trick, is the method I've successfully used for years. With real hard cases you may need to apply heat to the breech plug around the nipple.
On really stuck nipples I often use automotive ignition wrenches in metric or American sizes or cut a slot in a 1/4" drive socket to get the best fit as some nipple wrenches don't hold up well.
Once you have your barrel slug measurements taken I'll do my best to make a RB mold size recommendation. The original Jaegers I've rifles owned & shot all had deep rifling & required cotton pillow ticking with a high thread count to shoot the best groups. Likely won't find patches' on a dealers shelf, but take your micrometer to the fabric store & get a couple yards of the compressed thickness material you require & punch them out with an Arch punch on a hard wood or nylon surface after washing a couple times to get the sizing out.

Patch tip; I place stacks 50-75 patches & run a piece of nylon thread through the center with a needle to hang from my hunting bag. A knot at the bottom will prevent lost patches & allow for fast loading.
Happy trails !
Relic shooter

I slugged the bore and got grooves -.522, lands - .570.
Mike

 

[Old Hawkeye]

I slugged the bore and got grooves -.522, lands - .570.
Mike

The land diameter can't be greater than the grooves. ????? Least not on my rifles.

 

[Uncle Miltie]

I think he flipped 'em around.

 

[mikeinpa]

I think he flipped 'em around.

I certainly did. Thanks.

Mike