Help me slug my 44-40 please

[Stopsign32v]

This is my plan, will this work? I do not like the idea of just cramming a fishing sinker into a bore then measure it. So I got to thinking and want to know if this would work...

I could use a 44-40 casing and put a couple fishing sinkers in it.
Heat the casing to melt the lead.
After it cools I could remove the lead.

Shouldn't this produce a pretty much perfect tool to use to push down the bore of a 44-40?

My only other question is how do I measure the chamber? Heck, dumb question but where is the chamber of a revolver? Are we talking about the barrel end of a single cylinder chamber?

[Outpost75]

To measure the chamber neck of your .44-40 revolver, remove the cylinder from the revolver.

Take some soft pure lead muzzle-loader round balls of .445-.450" diameter and drop them into the chambers from the rear. If a .445 ball falls through the shoulder cone and chamber neck and stops solid at the ball seat, say a prayer of thanks for your good fortune, and just tap a bit more, to wedge the ball in the ball seat without driving it through, then tap it out and measure both diameters and you are done!

If the .445 ball fits tight at the shoulder and is a drive-fit into the chamber neck, tap it tightly into the neck of the chamber only to up, but NOT into the ball seat in front of the case. Then tap it back out and measure them with a micrometer.

To measure the diameter of the cylinder throat or "ball seat" do the same thing, except using smaller .430-.433" pure lead round balls and drive them ALL THE WAY through and out of the chambers, then measure them.

Well worth it to buy a couple boxes of pure lead Speer or Hornady round balls for this purpose. A box will do 15 or so cylinders if you only drop a couple. Yes, you WILL have leftovers, but this is the least expensive, safest way for a novice to do this. You can then be the great gun guru to all of your friends in being able to give them the proper implements for the job.

If you have a modern .44-40 revolver assembled with a barrel of ".44 Magnum" .429-.430 groove diameter, you want .44-40 chambers with a .447" neck diameter and .430 ball seat to have safe release clearance for a .430 bullet in Starline brass.

After you have measured your chambers, you can put the upset pure lead balls in your casting pot!

[Stopsign32v]

To measure the chamber neck of your .44-40 revolver, remove the cylinder from the revolver.

Take some soft pure lead muzzle-loader round balls of .445-.450" diameter and drop them into the chambers from the rear. If a .445 ball falls through the shoulder cone and chamber neck and stops solid at the ball seat, say a prayer of thanks for your good fortune, and just tap a bit more, to wedge the ball in the ball seat without driving it through, then tap it out and measure both diameters and you are done!

If the .445 ball fits tight at the shoulder and is a drive-fit into the chamber neck, tap it tightly into the neck of the chamber only to up, but NOT into the ball seat in front of the case. Then tap it back out and measure them with a micrometer.

To measure the diameter of the cylinder throat or "ball seat" do the same thing, except using smaller .430-.433" pure lead round balls and drive them ALL THE WAY through and out of the chambers, then measure them.

Well worth it to buy a couple boxes of pure lead Speer or Hornady round balls for this purpose. A box will do 15 or so cylinders if you only drop a couple. Yes, you WILL have leftovers, but this is the least expensive, safest way for a novice to do this. You can then be the great gun guru to all of your friends in being able to give them the proper implements for the job.

If you have a modern .44-40 revolver assembled with a barrel of ".44 Magnum" .429-.430 groove diameter, you want .44-40 chambers with a .447" neck diameter and .430 ball seat to have safe release clearance for a .430 bullet in Starline brass.

After you have measured your chambers, you can put the upset pure lead balls in your casting pot!


What is the ball seat? Is that where you see the "step" in a cylinder chamber? Where is the best place to find these Speer or Hornady round balls?

So am I not driving any lead through the barrel of the revolver?

[Harry O]

I have several 44-40's, have measured them, and have been disgusted with what I found. I start out with a slightly larger pure-lead ball for muzzle loading. They are available at Cabela's, Sheel's, Bass Pro Shop, etc. They are available in quantities of 50 generally, but I have seen 25 on occasion. It is best to have more than one for repeat measures. In this case, I would use a 0.451 (45cal) round lead ball.

I take out the cylinder and cut a wooden dowel about an inch longer than the cylinder window. A 3/8" dowel will work here. Keep the rest of the dowel (the longer section) for later use. Then, take the round ball and put it on the muzzle. Start tapping it in with a leather hammer. A wooden one would work, too. Don't use a metal one. When it is mostly in, press it fully into the barrel with the remainder of the wooden dowel (the longer section). There will probably be a small ring of lead that peels off. Ignore it. Then, put the cut down dowel into the cylinder window with 1" stuck up into the barrel.

Press the ball the rest of the way into the barrel with the remaining dowel. When it reaches the shorter dowel take a hammer to the end of the longer dowel sticking out of the muzzle and beat it. This will make sure the lead piece deforms outward and gets a true inside diameter. Just pressing it through the barrel without resistance will give an undersized reading. When you are done beating it, remove the shorter dowel from the cylinder window and press the lead slug out the rear of the barrel. Then measure.

You can also feel if there are large or small spots in the barrel while pressing the lead ball thorough the barrel. It is easy to press it if the barrel is in good condition. You can do the same thing to measure the different sections of the cylinder. In most recently made 44-40's, the cylinder throats are smaller than the barrel. That is why you don't press a ball through the cylinder first. Older 44-40's often have larger cylinder throats than the barrel, which is why you check the cylinder separately.

You will probably find a crazy mismatch of dimensions on a 44-40.

[Outpost75]

What is the ball seat? Is that where you see the "step" in a cylinder chamber? Where is the best place to find these Speer or Hornady round balls? So am I not driving any lead through the barrel of the revolver?

The cylinder throat or ball seat is the cylindrical portion in front of the case mouth to the front of the cylinder.

CORRECT! The old wives tail about "slugging the barrel" is absolute balderdash and has NOTHING to do with how well a firearm will shoot. The ONLY dimension which matters in ANY firearm, revolver, autopistol, rifle, is the diameter of the UNRIFLED portion of the chamber ahead of the case mouth before the rifling starts. The bullet should enter this without being forced, a slight resistance to "feel" or about 0.001" under is OK.

[Stopsign32v]

The cylinder throat or ball seat is the cylindrical portion in front of the case mouth to the front of the cylinder.

CORRECT! The old wives tail about "slugging the barrel" is absolute balderdash and has NOTHING to do with how well a firearm will shoot. The ONLY dimension which matters in ANY firearm, revolver, autopistol, rifle, is the diameter of the UNRIFLED portion of the chamber ahead of the case mouth before the rifling starts. The bullet should enter this without being forced, a slight resistance to "feel" or about 0.001" under is OK.

Wow, I'm getting much more knowledge than I bargained for!

OK...So I'm still not 100% sure what these terms are so I'm going to point to some stuff.

Outpost are you saying I need to slug this section of the cylinder chambers? Where you can see the rings: Which from what I can tell from eyeballing is the same size as the rest of the cylinder chambers...?

https://farm5.staticflickr.com/4348/36191535752_5167bf9425_c.jpg (https://flic.kr/p/X985FJ)

Or are you saying to slug this section before the rifling starts?

https://farm5.staticflickr.com/4341/36223422251_31126d514b_c.jpg (https://flic.kr/p/XbWvqX)

[Outpost75]

The front end of the CYLINDER as shown in your first pic. You can't tell; by eyeballing if they are the same size. You should drive SOFT lead balls through them all or use gage pins.

The chamfer in the barrel extension which protrudes into the frame window is called the "forcing cone"

I can see from the leading in your forcing cone that you are using bullets which are too hard and too small, such that the powder gases are washing away lead from the surface of the bullet and depositing it on the barrel walls. This also happens when the ball seat diameter of the cylinder is smaller than the groove diameter of the barrel, which sometimes happens.

That's why DougGuy has a niche business honing cylinders. He does a great job BTW.

[runfiverun]

that gun looks like it has had some work done to it.

follow Outpost's directions, and I would also take his warning about the too small/too hard thing to heart, I would guess that is where your problem is.

[rondog]

Use small hole guages and a micrometer.

[Stopsign32v]

that gun looks like it has had some work done to it.

follow Outpost's directions, and I would also take his warning about the too small/too hard thing to heart, I would guess that is where your problem is.

What do you mean "has had work done to it?"

It's a new out of box Cimarron Uberti 45 Colt SAA. This is not my 44-40 in question.

[Stopsign32v]

The front end of the CYLINDER as shown in your first pic. You can't tell; by eyeballing if they are the same size. You should drive SOFT lead balls through them all or use gage pins.

The chamfer in the barrel extension which protrudes into the frame window is called the "forcing cone"

I can see from the leading in your forcing cone that you are using bullets which are too hard and too small, such that the powder gases are washing away lead from the surface of the bullet and depositing it on the barrel walls. This also happens when the ball seat diameter of the cylinder is smaller than the groove diameter of the barrel, which sometimes happens.

That's why DougGuy has a niche business honing cylinders. He does a great job BTW.

Thanks for the clarification. I think I will go the hole gauge route.

When I get home I will list the bullets I use and size in the pictured 45 Colt

[mehavey]

Previous advice notwithstanding.....:???:

1. Go get some 44caliber round ball (Note they are 0.433"), and a piece of 3/8" dowel
http://www.jgsales.com/.44-caliber-hornady-lead,-.433-round-ball,-100ct-p-40386.html

2. Clean the barrel thoroughly, and then oil with whatever gun oil you have around (or even motor oil for this purpose)
3. Lube the roundball similarly (I use RCBS Case lube for what it's worth)
4. Lay the round ball on the muzzle and tap it in with a plastic mallet or piece of wood til flush
5. With a short piece of dowel, tap it into the barrel an inch to get started, then the rest of the way through. It will not be hard.
5a. If it goes through too easily (and doesn't leave a wide band on the ball), lay another ball on a hard surface and tap it a few times w/ a hammer to "squish" the ball to larger in diameter -- the perform 4 & 5 again.

6. Measure the resulting flat-worn/grooved band on the ball a few times -- that's your groove diameter
7. Take that same ball, and press it into the back of each cylinder and on through out the front. Ideally you should be able to push it through with a pencil eraser (cylinder throats should be at least groove diameter -- if really too much smaller, ream the throat out to groove+0.0005")

Cast SOFT (30-1/BN=6-7 for standard loads, and never more than Lyman#2 (BN=15) for that cartridge.
Size to groove + 0.001"

[Outpost75]

But I say again. Barrel groove diameter is not what matters.

Slugging your barrel is a complete waste of time.

Cast bullets should fit the THROAT.

Let's pound a wooden stake through the heart of this obsolete folklore for good folks!

[whisler]

Wouldn't slugging the barrel be necessary to be sure that the cylinder throats are larger than the groove diameter? Not for fitment but to be sure the throats are not undersizing the boolits. Otherwise it seems that undersized throats would result in undersized boolits. Am I misunderstanding?

[runfiverun]

the only reason to slug a barrel is to look for a tight or loose spot.
getting the bullet through the throat is the real deal, everything after that will take care of itself, unless you have one of the above barrel issues.


what I meant when I said 'work' was.
the throat in the barrel looked cut and the cylinder throats looked like they had some work done on them in the pictures.
but since those pictures were not of your gun it doesn't matter.

[Stopsign32v]

what I meant when I said 'work' was.
the throat in the barrel looked cut and the cylinder throats looked like they had some work done on them in the pictures.
but since those pictures were not of your gun it doesn't matter.

Those pictures were of my gun. Just a 45 Colt that I had laying around.

[mehavey]

Take the barrel groove. Period.
Check that the cylinder throat (if a pistol) is at least that.**
(If it's significantly smaller, you are fighting a losing battle no matter you size them to)

In the end you want the bullet to fit the barrel.
Even if you have to ream out the throat.

Add 1-2 thou and call it a day


**
Rarely do I find a throat that's significantly larger than the barrel.
(And when I do, as w/ my #3 Smiths, I still size just over groove diameter anyway since that's what the bullet first encounters)
postscript: SOFT. BN-15 or way less for a standard 44-40

[DougGuy]

I can see from the leading in your forcing cone>

What forcing cone? That is a terrible excuse for a forcing cone in the photo that OP showed. There is freebore there, but it looks more parallel to the bore than tapered, and the rifling is way too abrupt. This gun would shave lead off the boolits even if every other dimension was perfect.

This is the forcing cone of my Uberti, it was too small, and a tad off center, and the throats were huge at .4565" so I knew there was no way this tiny bit of shaving at the cylinder mouth on the barrel was gonna fly so I recut it before I even took the gun to shoot it the first time. I knew better, why waste ammo? This is what a forcing cone needs to look like:

http://i1202.photobucket.com/albums/bb374/DougGuy/Guns/DSC03772crop768_zpsznqzv9v8.jpg (http://s1202.photobucket.com/user/DougGuy/media/Guns/DSC03772crop768_zpsznqzv9v8.jpg.html)

And in case the Uberti photo is not convincing enough, here is my own 44 mag SBH which was a collection of radially oriented tool marks that Ruger called a forcing cone.. After cutting to 11 degrees:

http://i1202.photobucket.com/albums/bb374/DougGuy/44%20Magnum/DSC01739_zps53352b7c.jpg (http://s1202.photobucket.com/user/DougGuy/media/44%20Magnum/DSC01739_zps53352b7c.jpg.html)

If you have any mechanical abilities at all, you can rent the same cutter I used for both these guns from 4D rentals, the cost is very affordable and they have a very well done video showing how to attach/install the cutter and how to use it to achieve results like the two photos above. 2 important things. 1, use Tap Magic on the cutter, 2 GO SLOW and check often as it cuts rapidly.



That's why DougGuy has a niche business honing cylinders. He does a great job BTW.

Thank you sir you are too kind.

OP what kind of 44-40 is this? Ruger?

The problem(s) with the 44-40 are not easily cured. The biggest thing and the worst thing to contend with is that most mfgrs that are cutting cylinders for this chamber, use a 44 magnum barrel, which is either .429" or .430" in the groove diameter. 44-40 cylinders are usually throated at .425" or maybe .427" if you are lucky, and they will never work well in a .430" barrel because the boolits are just plain undersized which groups terribly and leads a barrel like nobody's business.

Well, ream the cylinder throats! That's easy enough! Not quite.. The neck of the 44-40 cylinder's chamber won't generally accept a round that has been loaded with a .430" or .431" boolit. The neck of the chamber itself needs reaming so that you can ream the throats to .4315" and use .431" boolits in your 44-40 which will then reward you with great accuracy and no leading. Provided you use a relatively soft alloy such as 50/50+2% and some soft lube.

If you are slugging the throats, and the gun is a Ruger or other 44-40 with a .429" or .430" barrel, it takes a lot more than just throat work to fix it.

[Stopsign32v]

OP what kind of 44-40 is this? Ruger?



It is a Uberti 1875 Outlaw

[DougGuy]

It is a Uberti 1875 Outlaw

Uberti says the groove diameter is .429" http://www.cimarron-firearms.com/bore-groove-twist

So we are at the scenario I described in my post. 44-40 is usually loaded with .427" boolits, and you would need to go larger to seal the bore.

[mehavey]

I'm running 0.429 in both my Uberti/Taylor-SmokeWagon'd SAA 44-40; and my Uberti/Taylor-Commanchero'd `73Win 44-40
Both run perfectly using Starline & Rem brass.

Both love as-loaded BlackHills, and my own handload that effectively duplicates that.
https://thefiringline.com/forums/showpost.php?p=6065580&postcount=7

[Stopsign32v]

Uberti says the groove diameter is .429" http://www.cimarron-firearms.com/bore-groove-twist

So we are at the scenario I described in my post. 44-40 is usually loaded with .427" boolits, and you would need to go larger to seal the bore.

So Doug correct me if I'm wrong but it sounds like my chambers will be much undersized over my bore, resulting in poor accuracy? I need to measure first but the gun won't be here until next week.

If this is the case how do I get it corrected?

[Stopsign32v]

The front end of the CYLINDER as shown in your first pic. You can't tell; by eyeballing if they are the same size. You should drive SOFT lead balls through them all or use gage pins.

The chamfer in the barrel extension which protrudes into the frame window is called the "forcing cone"

I can see from the leading in your forcing cone that you are using bullets which are too hard and too small, such that the powder gases are washing away lead from the surface of the bullet and depositing it on the barrel walls. This also happens when the ball seat diameter of the cylinder is smaller than the groove diameter of the barrel, which sometimes happens.

That's why DougGuy has a niche business honing cylinders. He does a great job BTW.

Ok so the bullets that I use for this revolver are these.

http://missouribullet.com/details.php?prodId=49&category=5&secondary=14&keywords=

[DougGuy]

So Doug correct me if I'm wrong but it sounds like my chambers will be much undersized over my bore, resulting in poor accuracy? I need to measure first but the gun won't be here until next week.

If this is the case how do I get it corrected?

First thing is to figure out what you have. Get ahold of a couple of jacketed bullets if you can, a .429" and .430" which are common sizes for 44 caliber made by many mfgrs. See if you can push these into the cylinder throats from the front. If they go, then try and use the .430" size for your cast boolits as this is "theoretically" .001" larger than groove diameter.

You could alternately order some single gage pins from Meyer Gage Co. I would get some Minus pins, these are .0002" under, in the sizes of: .427" .4275" .428" .4285" .429" .4295" .430" which should run you maybe enough to get their minimum order which is $25. If that falls short, add .4305" and .431" and that should get you there. This is the cheapest way to get a precision measurement.

Hole gages and then measuring with a micrometer only measures across the hole, and there is usually the chance for erroneous readings since no two people will perceive the tightness or lack of, in the cylinder throat for the correct "feel" to set the hole gage and then the same with the mic. Calipers are out totally as you will get more mis information from them than information. Pin gages, actually assimilate the geometry of a boolit, they gage the entire hole not just across the center of it, and they act like the boolit will act, if you have an oval throat a pin gage will find it, if the throats are uneven, pin gages will find it in a heartbeat and they will be accurate about it.

You have time to get these from Meyer, and let's not go and put the cart in front of the horse until the gun arrives and you have accurate measurements.

Remember that the 44-40 of old used a pretty soft lead boolit so you could shoot one from a .427" cylinder into a .429" barrel and have great accuracy and no leading because the pressure from burning gas will obturate the boolit and seal it in the bore once it clears the cylinder throat. *IF* you got a soft enough alloy and soft lube!

[Outpost75]

And don't worry about leading from "too soft" lead. This is another old wive's tale which needs to be buried.

With respect to the .44-40 and similar black powder era cartridges, the bullets in original BP ammo were either pure lead, or only minimally "sweetened" with a small amount of tin, 1:75, 1:50, 1:40 were typical mixes before 1900. 1:20 and 1:16 tin-lead were considered "hard" alloy in their day, being about 8 BHN, versus 5-6 for pure lead.

I use 1:30 tin-lead from Roto Metals for all of my revolver bullets in "non-magnum" calibers, such as the .32-20, .32 S&W Long, .38 Special, .44-40 and .45 Colt. This approximates the hardness of modern factory lead bullets and works wonderfully for subsonic revolver velocities and in rifles up to the velocity limitations of plainbased bullets, about 1300-1400 fps. With gaschecked bullets 1:30 provides wonderful game performance in full-charge Winchester '92 and 1894 Marlin levels up to 1600 fps, and also for standard-pressure full charge loads in the .44 Magnum revolver, when bullets "fit" and are properly lubricated.

[Stopsign32v]

Thanks Doug! That is exactly what I will do. So this is what you are saying to look at? http://www.meyergage.com/products/individual-gage-pins/

Another question I had and you actually might have answered it. My indoor range will not allow lead bullets so when I go to shoot my 9mms, the cowboy guns have to sit at home. Could someone use .44 Cal RMR plated bullets in 230gr for 44/40 loads with smokeless powder like Unique? They are 0.429" and from my understanding the modern 44/40s are this size to minimize tooling AKA manufacturers can use the same process as 44 special barrel for 44/40 revolvers as well.

[Stopsign32v]

And don't worry about leading from "too soft" lead. This is another old wive's tale which needs to be buried.

With respect to the .44-40 and similar black powder era cartridges, the bullets in original BP ammo were either pure lead, or only minimally "sweetened" with a small amount of tin, 1:75, 1:50, 1:40 were typical mixes before 1900. 1:20 and 1:16 tin-lead were considered "hard" alloy in their day, being about 8 BHN, versus 5-6 for pure lead.

I use 1:30 tin-lead from Roto Metals for all of my revolver bullets in "non-magnum" calibers, such as the .32-20, .32 S&W Long, .38 Special, .44-40 and .45 Colt. This approximates the hardness of modern factory lead bullets and works wonderfully for subsonic revolver velocities and in rifles up to the velocity limitations of plainbased bullets, about 1300-1400 fps. With gaschecked bullets 1:30 provides wonderful game performance in full-charge Winchester '92 and 1894 Marlin levels up to 1600 fps, and also for standard-pressure full charge loads in the .44 Magnum revolver, when bullets "fit" and are properly lubricated.

Outpost also, thank you for your helps as well!

[runfiverun]

once you get the gun figured out.
and your cast stuff figured out.
then just get the plated stuff the closest to your lead bullets in diameter and shape and use the same loads.

[gwpercle]

Stopsign,
This may have been mentioned , but in case it wasn't , it helps to lube/grease the barrel or chambers before driving lead slugs through....jus makes life easier and you wont have to find that sticky on removing broken wooden dowels from barrels.
Watch a couple U-tube video's on it and it will make more sense !
The Lyman manual recommends using boolits sized to .429 , you could buy a few load them up and see how they work...sidestep that pesky slugging thing altogether , this is the old fashioned way.
Gary

[DougGuy]

Thanks Doug! That is exactly what I will do. So this is what you are saying to look at? http://www.meyergage.com/products/individual-gage-pins/

Yep, you want English, Class Z, Minus pins..

[Harry O]

There have been a lot of good replies on this thread. Unfortunately, most of them apply to calibers other than the 44-40. The 44-40 is unique unto itself. I have measured 5 of them from 4 different manufacturers (three rifles including an original 1873 and two handguns) and EVERY one of them had far different dimensions when compared to each other. I never did find a bullet that would shoot well in all of them.

By far the worst were Ruger Vaquero 44-40's. I bought two of them when they first came out for CAS shooting. The neck of the chamber would not take any larger than a 0.427" bullet or the cartridge would get stuck in the chamber. The throats ahead of the neck were 0.424". The barrel was 0.430". The groups with factory ammo ran 6" to 9" in diameter from 15 yards from a rest. There is NO possible way to get dimensions like that to shoot without a trip to the gunsmith (they were originally returned to Ruger, who returned them without changing anything saying it "met their machining standards"). However, do not think that mismatched dimensions are limited to Rugers. The rifles had messed up dimensions, too, just not quite as bad.

If you do not check the largest bullet that will chamber, check the throat (in a revolver), and check the barrel, you don't have a clue on what it will take to make it accurate (if it is even possible to do that without the help of a gunsmith). No one dimension check will tell you what you need to know about this caliber.

[HP9MM]

Order some .44 bore slugs from LBT. They are easy to use. I used them on my Model 29-2 and then measured them.

[DougGuy]

Order some .44 bore slugs from LBT. They are easy to use. I used them on my Model 29-2 and then measured them.

As opposed to pin gages?

[Stopsign32v]

I just wanted to update that a member here was very kind enough to send me some .429 bullets to try out in reloading. I don't have a die set or brass yet for 44-40.

However I did place the .429 bullets in the chamber throats of the cylinder and they all went in the throats with the slightest of finger pressure pushing them in. So with that said should I be good to go in using .429 bullets?

[Outpost75]

I just wanted to update that a member here was very kind enough to send me some .429 bullets to try out in reloading. I don't have a die set or brass yet for 44-40.

However I did place the .429 bullets in the chamber throats of the cylinder and they all went in the throats with the slightest of finger pressure pushing them in. So with that said should I be good to go in using .429 bullets?

If you could feel slight resistance pushing them in, that is about right.

[Stopsign32v]

If you could feel slight resistance pushing them in, that is about right.

Fantastic!

I would like to thank everyone that has helped me in this thread.

[Larry Gibson]

My 44-40 SA is an old model Ruger Vaquero. The throats pin gauged .430 and taper to .429 at the front. Barrel groove diameter is .429. I use W-W cases and use .430 sized 200 gr RFs and 245 gr 429360 SWCs. With TL240 SWCs which I seat out to and crimp in the 2nd lube groove need to be sized .429 to chamber w/o thumb pressing.

Accuracy is excellent, as good as I can shoot, with the 240/245 gr SWCs. No leading ang 12 shots go into 2" +/- over sand bags at 25 yards.

[indian joe]

But I say again. Barrel groove diameter is not what matters.

Slugging your barrel is a complete waste of time.

Cast bullets should fit the THROAT.

Let's pound a wooden stake through the heart of this obsolete folklore for good folks!

I'm gonna call ya on that one - if your cylinder throat is smaller than groove diameter - you shootin an undersize pill - need to slug the barrel - then make sure cylinder exit point is sized correctly to that - also lotsa blackpowder rifles out there with little or no freebore (throat) - slug the bore is easy and its a start - got a lever gun ? need to take the bolt out to slug the throat the way you describe - aint gonna happen in many cases.