How to get the actual calibre from the marketed calibre? (and other stuff too)

P

Pond James Pond

New member
Apologies in advance but the more I learn about BP shooting the more I realise I don't know and it's frying my brain!!

So, I've been researching the Remington Revolving Carbine for a little while now. It is marketed as a .44 cal. However, it takes round-balls at .454 cal.

Being a revolver this is because it is loaded into the cylinder which will direct the bullet in to the forcing cone and rifling. The .44 cal apparently comes from the land to land diameter in the bore.

However, then come conicals. They could also run with the 1:38 twist (and are perhaps even better suited), but at what diameter?
Same for a possible purchase of the Smith carbine or Hawken in .50cal.
Same problems!

What is the rule of thumb for adding diameter or substracting diameter from a given bullet type for a given calibre in Muzzleloading?

Which bullet types need to be over-bore and which under?

How do I know what patch thickness to get?
Do I need a patch or a wad of something?
How big should they be?

Then there seem to be a myriad of lubes!
How much lube do patches and bullets need and which type?
 
I wish there was one!

For the .44 use the same diameter for conicals that you'd use for RB. (0.454").

For actual muzzle loaders (as opposed to revolving guns which do not actually load at the muzzle) the usual starting point is bore diameter minus 2X the patch thickness. For a .50 that is actually .50 that's a ball of 0.490" & a patch of 0.005". For bullets (like minies or Lyman REAL which don't use patches) match the diameter to the bore diameter.

In practice a little fudging is usually required but those are good starting points.

Lubes break into "dry" & "wet" & patch lubes are different from ball or bullet lubes.
Patches are usually allowed to absorb a liquid lube (like Ballistol diluted with water & left to dry.) or for traditional lubes Google "Moose Milk", "Moose snot" & "Moose Grease" & so on.

Balls & bullets usually use a "grease" of some kind. Never petroleum based though as it forms horrible deposits. I use a commercial product but you can make a traditional one with a 50/50 mix of beeswax & "Crisco" shortening heated to melt & mixed together.
 
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A 44 or a 36 caliber cap and ball - originally - were bored those dimensions and THEN rifled. Thus a 36 caliber will have a groove diameter larger than .360.

That is why "conversion" revolvers - converted from C & B to cartridge, required the used of a "heeled" bullet.

Todays reproductions - I'm talking cartridge - are rifled to modern specs. I.e. - a 36 caliber Richards & Mason conversion (sold that way by Uberti for example) will have a standard .357 barrel for using "modern" bullets. The same with the Army Conversion (made that way) will use the "modern" bullet as used in today's 45 Colt.

A C & B revolver - use 36 caliber as an example - will be bored the "old way" - i.e. with a bore of .360 and THEN rifled so the groove diameter is larger than .360. Loading the .36 for example, with a .375 ball, will shear the "lead circle" when seated in a chamber - necessary for tight fit and necessary so that when fired, you won't get a "chain fire" - hopefully! :) The .375 ball, already reduced in diameter by the seating in the cylinder, is then forced when fired into the forcing cone and then rifling - which is of course larger than .360. The same applies for a .44 Army caliber - whether Colt or Remington.

If you convert a C & B with something like a Kirst cylinder, etc. - you'll still have to use a "heeled" bullet or similar that will expand into the rifling to have a good bore fit.

Older revolvers chambered in 45 Colt, Schofield, etc. utilized a .454 mold as that is what the original cartridge utilized - as well as the old revolvers. The common mold for example was a 454-160 which cast a 250 grain round nose traditional cast lead bullet. Today, most of the reproduction cartridge revolvers are made to the "modern" specs which utilize a .452 mold.

Don't know if that helps at all? As far as the Remington carbine - you would load it the same as you do a C & B revolver. You do not use a patched ball.

You then switch to ML rifles which is a whole different ball game than the C & B revolver.

Usually, but not always - for a muzzle loading rifle utilizing a patch - you would use a ball .010 or .005 smaller. In other words - in a 45 caliber rifle - a .440 or .445 ball. Patch thickness depends on the rifle itself, depth of rifling, etc. What works best in one does not always work the same in the next. And . . just because the barrel is stamped a particular caliber - does not mean that it IS that caliber. You really need to slug the bore, measure it and go from there. I have an older Hopkins & Allen under hammer that is marked .45 caliber. The barrel was made by Numeric which was well known for having some barrels that were "under size". I'm doing some repairs to it as it was in pretty sad shape when I got it. I haven't slugged the bore yet but I imagine I might have to go to a .437 or even a .433 size ball due to the undersize bore. Patch thickness will be determined by the ball size.

Do some googling on dertermining patch thickness for a muzzle loading rifle. There should be a number of good reads on how to do it. The Lyman Cast Bullet Handbook (3rd edition) does a good job of explaining it. If yu don't have access to a copy - PM your email to me and I'll scan it off for you in PDF.

Lubes? There are "oodles" of different lubes - everyone will tell you theirs is the "best". The purpose of the lube is to keep fouling soft. I have shot BP for over 50 years - everybody does it different. On a round ball rifle - I normally fire a "fouling shot" - either just powder or an actual load. The first shot out of a clean barrel will often be a "flier". I then spit patch the bore between shots - using a dry patch with a little spit - run it in and out of the bore and then re-load. But that's just me - others do it differently.
 
If you convert a C & B with something like a Kirst cylinder, etc. - you'll still have to use a "heeled" bullet or similar that will expand into the rifling to have a good bore fit.
Click to expand...

That is not quite correct. Yes, for a 36 caliber C&B revolver if you put a conversion cylinder in it, you will have to use a hollow based bullet to expand and fill up the rifling, or you will have to sleeve the barrel for .357 bullets. A friend has a pair of 1851 Navy revolvers and he had the barrels sleeved so he could fire conventional .357 bullets in them, loaded conventionally into 38 Special cases.

However the story is different with 44 caliber C&B revolvers. I have two 1858 Remington New Model Army revolvers with Taylors/R&D conversion cylinders. Here is one of them.


Remmie.jpg



By chance, the rifling groove diameter of a 44 caliber C&B revolver is just about perfect for 45 Colt cartridges with conventional .452 bullets. I slugged the bore of this revolver a long time ago. The rifling diameter is .449. A little bit tight for 45 Colt, but it works fine. I have not slugged my other Remmie, but it shoots 45 Colt fine too. I can also fire 45 Schofield ammo in these revolvers, with conventional .452 bullets. If one wants to shoot 44 Colt in these revolvers, then yes one will need heeled bullets, or hollow based bullets to expand to fit the rifling. And a 44 Colt cylinder. But the most commonly done conversion of these revolvers is using a 45 Colt cylinder, made either by Kirst, Howell, or Taylors, chambered for 45 Colt. But they work just fine with conventional 45 Colt bullets loaded into 45 Colt or 45 Schofield cases. I only shoot my Remmies with Black Powder, but if I wanted to I could shoot light Smokeless loads in them too.
 
How does one slug a barrel? I've seen the term, but never seen it explained.
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I second the question. I understand that it involves driving an over-sized lead object (round-ball?) down the bore so that you get the exact dimensions of the bore, both between the grooves and lands. I believe a dowl of near-bore diameter is idea

I also believe that if done carefully you can also discern any changes in resistance that might indicate an inconsistent bore, less resistance being a widening and an increase being a tightening.

I do hope others will elaborate as I've never done it and I'd like to know how.

For example, taking that .44 remington as an example, would one of the .454 round-balls suit?
 
using a dry patch with a little spit
Click to expand...

Finally something in shooting that is cheap!!
:D

Thanks for the offer of some info via email: PM sent!!

Overall, it does seem like conicals are a little less hassle to load up: one step less with no patch to source, prep and measure.
 
You need pure, soft lead, a little over bore diameter.
You apply lube, lots of it, to the internal bore & the object you're using as a slug. LEAD fishing "torpedo" weights are popular. Be careful though many aren't pure soft lead any more.
Now you secure the bore to be slugged so its firmly held in place with out being crushed.
Take some hardwood doweling just under bore diameter & a tad longer than the bore.
hammer the lead slug through the bore till it exits onto a soft surface (folded towel is fine) & measure the "negative image" of the bore.

This will give you the minimum internal bore diameter.
 
Nice description! Thanks.

Well I have the dowel, and I was planning to use a single plated bullet for my Redhawk. They seem pretty soft, but I couldn't say if they are pure lead under the plating or not. They also have a polymer coating that aids movement in the bore. I hope ballistol would work for the lubing aspect.

They are conical meaning they'd feed easily into the bore and have a concave end meaning that they could be driven with the dowel squarely centred on the bullets base in that concave dip: a somewhat minie-esque shape, in a way...

As a clamp, I could use my work bench in the garage: it is wooden and so shouldn't affect the gun's barrel.
 
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ROUND BALLS
in a muzzleloading pistol or rifle are about 5 to 10 thousandths smaller than land to land diameter of the barrel, because they are normally wrapped in a cloth patch, that is about .010 thick. the patch forms the gas seal

In revolvers the ball is about .003 to .006 larger than the chamber size.
During loading, this excess is shaved off and rest is squeezed (swaged) into the chamber, thus creating a friction fit and a gas tight seal.
Properly machined the chamber is normally about .446 to .449 inches.
The barrel bore is .440 (thus you 44 cal) land to land.
The forcing cone further squeezes the ball down in size as it goes through and rolls some of the excess lead backwards thus further creating a gas seal as it enters the lands and grooves.

CONICALS
Muzzle loading rifles and pistols.
Normally have lube grooves and are about .002 larger than bore diameter.
This along with the lube allows them to cut into the rifling as they are seated thus creating a gas tight seal and no patch is needed.
the lube reduces the friction during loading, helps keep fouling soft afterwards, and acts as a gas seal.

In Revolvers, pretty much the same.
they have lube grooves and are about .002 to .006 inches over size.
Most have rebated heels to make easier loading.
For instance the custom ones I cast
the heel is .446 the first sealing band is .451 the top sealing band is .455
this "tapered" design, allows easier starting in the chamber, and easier to keep straight and centered while loading. And creates a good tight seal.
These rarely shave a lead ring, as the excess is rolled forward as it is being seated.
The bottom ring is swaged and rolled forward into the grease groove and the upper is rolled a bit too.
They are about 50 grains heavier than the round ball at 190 gr.

Neither round balls or conicals use patches in a revolver.
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Muzzle loading round ball and patches.
Normally there are two round ball sizes and patch thicknesses.
IE: 50 cal .490 and .495 round balls are common.
patch material cotton .010 to .012 thick and pillow ticking . 016 to .018 thick.
Normally .490 plus the .018 patch as this brings you just above bore diameter
But it is a trial and error to see which of the 4 combinations work best in your gun.

The conicals in revolvers. Lee was one of the first to offer moulds for this.
their original was 45-200

the bullet was 200 grain and was .450 from base to the start of the ogive(rounded part into the nose)
But that wide flat base made it a bitch to get it started in the chamber. Thus after a few years they rebated the heel a bit.
Custom mould makers also rebated the heel.
In mine above, I requested the mould maker for those specific dimensions, making it easy to load, but yet tight enough to make a good tight seal.
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lubes
I would stay away from crisco altogether.
If making your own use lard (tallow) which is animal fat an beeswax.
BTW: toilet bowl rings are not necessarily pure beeswax any more don't use them.
petroleum based lubes in muzzleloaders, tend to leave a hard nasty deposit behind, so no petroleum based.
Bore butter or such is good for patches, but like crisco, too soft for an overball lube.

Hollow base bullet is not the same as heeled.
Heeled the base is smaller in diameter than the rest of the bullet
hollow base, the very bottom of the bullet is hollow like a spoon.
this hollowness allows the hot gases from ignition to force the thinner edges outward to make a better gas seal.
Is ok in a cartridge conversion and even in a muzzleloader, but not really needed in a standard C&B revolver, even though they are used in them by some people.
 
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I use Bore butter to grease the wads that I make. I have a set of hole punches so I use one of the correct size and punch out wads out of a torn flannel short. After the wads are greased I store them in an empty shell of a chapstick tube. I use the wads that I make for over powder and use an oxwad over the ball. for long term storage of a loaded cap and ball I use the bore butter and form a bead of grease along the edge of the over bullet wad.

I have had BP revolvers charger for more then three years and had them fire fine. On one occasion I dropped one gun in a puddle and only one cylinder require a new percussion cap to fire.
 
Howdy

I NEVER clamp the barrel in place when I slug a bore. And you don't really need to lubricate the barrel either, I did it dry for years. And I have used everything from hard cast lead bullets, to dead soft lead bullets.

Here is my handy-dandy guide to slugging a bore, I wrote it up a bunch of years ago. Yes, there are other ways to do it, but this is the way I do it.

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Slugging a Barrel
There are lots of ways to slug a barrel. Here's how I do it.

First off you need to come up with a slug. I have used all sorts of things to slug barrels. Ideally, your slug should be just a few thousandths larger in diameter than the grooves you are slugging. If it is too big, you spend a lot of effort driving it into the muzzle in the first place. I have used soft cast bullets, hard cast bullets, soft lead round balls, whatever I have laying around that is just a tad larger than the bore I am trying to measure. I have even taken a 44 caliber soft lead round ball and hammered it down to a rough bullet shape in order to slug a 30 caliber rifle. Some folks also use lead fishing sinkers, if you can still buy them where you live.

When I slug a rifle I lay the gun down on a soft towel on my bench. Or else I support it in a felt lined rifle rack. I do not jam it in place so it does not move. I allow it to slide slightly with each hammer blow, hence the soft towel or felt to protect the finish. I used to slug bores completely dry, but lately I have taken to running a patch dampened with Ballistol down the bore. You don't have to soak the bore. Frankly, I don't think it makes much difference if the bore is lubricated or not, I've done it both ways and don't really see much difference.

Whenever possible, I will slug a bore from the chamber end. However with revolvers and most lever guns it can only be done from the muzzle end. I start with a short rod, only around 8 or 10 inches long. It is much easier to control a short rod when you are whacking it than trying to whack the end of a 3 foot long rod while still trying to hold onto the gun. I grasp the muzzle in my left hand, and jam the slug into the muzzle so it holds still. I also hold the rod in place with my left hand, leaving my right hand free to use the hammer. I place the end of the short rod on the center of the slug to get it started, grasping both the muzzle and the rod in my fist. I like to use brass rods. Some prefer wood, but I find wood splinters and shatters. I start with a brass rod about 10 inches long. I have a few lengths. 5/16" diameter will work for everything from 38 (.357) on up to 45.

Most any hammer will do, I have a nice 8 ounce ball peen hammer that works well.

The key here is to not hit the muzzle with your hammer. I start with the short rod. Getting the slug completely into the bore is the hardest part. Once it gets into the bore, it moves more easily. Don't be scared, I have never gotten a slug stuck in a barrel. Just be careful. I change the short rod to a longer rod long before my hammer gets anywhere near the muzzle so I don't risk striking the barrel. I change over to a 3 foot rod to run the slug all the way out the bore of a rifle. I keep a soft cloth by the chamber, so the slug will fall out onto the cloth without marring it.

With a revolver I stand the gun up with the barrel horizontal and the butt resting on the towel on the bench. The procedure is the same. I grasp the muzzle and the rod with my left hand, I jam the slug into the bore, and I control the rod with my left fist. The right hand is for the hammer. A 12 inch long 5/16" rod usually works for all my revolvers.

A few facts about slugging a barrel. The slug only measures the narrowest diameter of the rifling. If there is excessive wear near the chamber, like with some old rifles, the slug will slide along easily through the worn part, it has already taken the shape of the narrowest part of the bore. With a new gun, this should not be a concern. However with an old gun, it can give you a feel for if there is wear in the bore.

The slug must completely fill the rifling grooves. If the slug did not completely fill the grooves, any measurement you take off of it is meaningless. When your slug emerges, look for lengthwise drag marks on it. You should see these marks on both the low spots on the slug, corresponding to the lands of the rifling, and the high spots, corresponding to the grooves. If you don't have drag marks on the high spots, you may not have completely filled the rifling grooves, and any measurements taken from the slug are meaningless.

I hear a lot of guys say you have to measure a slug with a micrometer so you can measure it right down to the .0001 level. Frankly, I think a standard caliper is fine for measuring a slug. Measuring down to .001 is fine, particularly on a dial caliper, where you can interpolate what the dial is telling you between the tick marks. A digital caliper will round off to the nearest .0005, so you may not get as accurate a measurement. But using a micrometer that measures down to .0001 on a soft lead slug is overkill, in This Cowboy's Humble Opinion. Just the act of closing the tool on the slug will deform the lead a couple of tenths, killing the usefulness of the accuracy of the micrometer.

Obviously, you want to measure across the high spots of the slug, to get your groove depth diameter. This is simple if the rifling has an even number of grooves, so that you are measuring across the diameter of the slug. Some barrels though, like many S&W revolvers have 5 grooves. It is very difficult to get an accurate measurement on a slug made from a barrel with an odd number of grooves with a caliper or a micrometer. If you try to add the depth of one side of the rifling, there will usually be some error involved. It ain't impossible, but it is tough.

Slugging a bore is really very simple, I have made it sound complicated. It usually only takes me about 5 minutes to set up to slug a bore, and about 5 minutes to run the slug all the way through. The key is finding a suitable slug just a little bit oversized, and don't whack the barrel!
 
Slugging a bore is really very simple, I have made it sound complicated. It usually only takes me about 5 minutes to set up to slug a bore, and about 5 minutes to run the slug all the way through. The key is finding a suitable slug just a little bit oversized, and don't whack the barrel!
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The detail is appreciated. I have 10mm doweling right now and that is about 2mm narrower than my .44s bore.

I am curious as to what you think of my proposed slug
(from an earlier post):

I was planning to use a single plated bullet for my Redhawk. They seem pretty soft, but I couldn't say if they are pure lead under the plating or not. They also have a polymer coating that aids movement in the bore. I hope ballistol would work for the lubing aspect.

They are conical meaning they'd feed easily into the bore and have a concave end meaning that they could be driven with the dowel squarely centred on the bullets base in that concave dip: a somewhat minie-esque shape, in a way...
Click to expand...
 
I suggest you find a lead bullet. I have never tried slugging a bore with a jacketed or plated bullet. As I said, the bullet does not have to be soft lead, a regular hard cast bullet can be used, I have done it lots of times. It also does not matter if the bullet has a cup at the rear to encapsulate the end of your rod. Just place the rod at the center of the bullet when you start. As I said, I prefer a metal rod, because wooden rods tend to shatter.
 
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