Id like to convert a modern sxs 12ga to black powder muzzleloader. I have the adaptors to plug the breech end. Now the question of choke and forcing cones. Should the forcing cones be altered or lengthen if using felt wads? Should the chokes be opened to cylinder for ease of muzzle loading or is there an alternate way to load felt wads and over powder and over shot cards thru chokes?
Converting a modern double to muzzleloader
- Thread starter brybenn
- Start date
Would a muzzleloader typically have forcing cones and/or chokes? Can't say I know a lot about front-stuffers..
Also gotta ask why would you want to do this? Just for the hell of it? Or is there a more significant reason (not that there needs to be...)?
Also gotta ask why would you want to do this? Just for the hell of it? Or is there a more significant reason (not that there needs to be...)?
- Location
- Western Manitoba
I would be interested to hear a bit more about your idea - I am sure I had read about conversions by installing new barrels and mono-block to a shotgun hinged receiver, but do not think I had ever heard of using the shotgun barrels for muzzle loaded black powder? So, a breech plug that uses an "in-line" primer to use the internal firing pins? A smooth bore musket type firearm? I suspect to load and fire patched balls that there can not be any choke at the front end of barrel, but I have never tried such a thing, but perhaps you have something else in mind?.
There is a currently made 12ga Howrah pistol called the Diablo that is built along the lines that you are talking about(break action 209 primers)I have a muzzleloading double that has cylinder and modified chokes and loading wads pose no problems.I do know that if you were using custom made breechplugs to permanently convert the gun to a muzzleloader you would have to get rid of the forcing cone as it would cause an unwanted air space that could blow up your gun but I don t know if you would have the same issue with temporary adapter plugs.I use to have a copy of Brockways recreating the the muzzleloading shotgun and he states this issue with forcing cones if you are adapting a pair of breechloading barrels to muzzleloading
Also traditions made a over/under 50cal muzzleloader express rifle built with a modern break open action and 209 primers
Also traditions made a over/under 50cal muzzleloader express rifle built with a modern break open action and 209 primers
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Of course original vintage muzzle loaders had no forcing cones and no chokes. Felt wads were commonly used. Forcing cones for the transition of the shot from cartridge shell to the barrel interior was usually very abrupt on early black powder cartridge guns to try to get the best seal with the common wads of the day, which again was often felt. And throughout this period up until about the early 1870's choke didn't exist either but sort forgotten in firearms progression is the fact that the transition from muzzleloader to break open guns wasn't sudden. Breech loaders came into use in the early/mid 1850's and by the late 1860's had become the most prominent form of new guns being produced but old traditions die hard and muzzle loaders continued to be produced well past 1900.
Old timers clung to tradition, many shooters didn't trust these new contraptions and while powder, caps, lead and shot were available in any far flung point on earth the correct fixed ammunition for a specific breech loader might not be.
These later muzzle loaders, some of them still of best quality, of course still had no forcing cones and I've never heard of one with original choke boring. One problem I see with your idea is that the overpowder wad needs to be quite hard and a good seal against the barrel walls. This is commonly fibre, card or occasionally cork. Something like this would be a problem to start in a choked barrel. Same for the over shot card which needs to be rigid. Bare felt against the shot would end up with various amounts of the shot payload embedded in it, the felt needs to be protected from the shot, it's just a cushion in a muzzle loader.
Old timers clung to tradition, many shooters didn't trust these new contraptions and while powder, caps, lead and shot were available in any far flung point on earth the correct fixed ammunition for a specific breech loader might not be.
These later muzzle loaders, some of them still of best quality, of course still had no forcing cones and I've never heard of one with original choke boring. One problem I see with your idea is that the overpowder wad needs to be quite hard and a good seal against the barrel walls. This is commonly fibre, card or occasionally cork. Something like this would be a problem to start in a choked barrel. Same for the over shot card which needs to be rigid. Bare felt against the shot would end up with various amounts of the shot payload embedded in it, the felt needs to be protected from the shot, it's just a cushion in a muzzle loader.
- Location
- Western Manitoba
Good points, Ashcroft! I had not even thought it to be a muzzle loading shotgun!! Had the conical or ball muskets in mind. I would have thought working up a cartridge load using black powder in the cartridge would be the way to use "black powder" in a shotgun - but then there is the whole "loading down the muzzle" thing that might appeal??
I hunt deer in a muzzleloading only zone. Small woodlots the shots on deer are often very close. Often less than 15 yards. Id like to try buck shot from a sxs for those times more than one deer stroll by. Often after the shot the other deer stand close by and watch me reload. A sxs i could get a double easily. I also just want to play around and try new things. I have a pair of 209 inline adapters i judt dont want to modify a current sxs i own so i was going to pick up a decently made cheaper sxs maybe even even an external hammer gun for added fun. The pligs are removable so i could load black powder shells and use it for skeet shooting as well as a cartridge gun. I was debating opening the chokes to cylinder or just cutting the barrels behind the choke. Cast some slightly hard 00 or 000 buck and see what patterns the tightest and wait for a deer to make a mistake this November.
Slugs are not to be used with the adapters but a load of buck shot will work. I could also load it with smaller shot for small game. Again just to be different. I love my muzzleloader rifles but it would be fun to carry a shotgun some days
Id just have to carry around the ramrod separately which is easy enough
Slugs are not to be used with the adapters but a load of buck shot will work. I could also load it with smaller shot for small game. Again just to be different. I love my muzzleloader rifles but it would be fun to carry a shotgun some days
Id just have to carry around the ramrod separately which is easy enough
- Location
- Western Manitoba
OP - there is another CGN thread on the go - "20 gauge from hell" or similar title - part way through, a specific book is mentioned. Probably want to get a read that one - the writer has been doing the conversions for quite a while, apparently. Online discussions on 24 hour campfire or maybe Practical Machinist mention other references that allow you to do the beech pressure calculations for what you want to end up with - seems to be mostly about cartridge (breech loaders), not muzzle loaders, though. I hope that you have some basis to believe that shotgun barrels will work - looking at pressures for shotguns, I think they run in the 11,000 psi to perhaps 14,000 psi levels? From Lyman Black Powder book, seems black powder loads can easily double that, if not more?
With black powder shotgun loads, muzzle loaded loaded or in a cartridge, it's easy to duplicate original black powder ballistics and pressures. In a 12 gauge you want a powder charge of 2 3/4 to 3 drams of FFG by volume behind 1 1/8 oz of shot, any size. This will give you a standard 12 gauge load of 1150 to 1200 feet per second at less than 6000 psi pressure. This is well under modern smokeless powder pressures and is well within the pressure limitations of any shotgun, new or old in good condition.
Everything ive read and experienced black powder has way less pressure than nitro. If black powder made more pressure than smokeless we could run smokeless in black powder proofed guns safely and thats certainly not the case
- Location
- Western Manitoba
I think that you are correct about the pressure numbers, but need to think of the application? So, SAAMI sets service load pressures in the range of 11,000 psi through to about 14,500 psi for various gauges - I could not find SAAMI's "proof pressure" levels, but CIP has general principle of 1.25 the maximum service pressure - so, I am presuming that a modern smokeless shotgun is "proofed" to 14,500 psi x 1.25 = 18,125 psi for a 3.5" 12 gauge - about the highest "service pressure" that that I could find listed. Most other cartridges lengths and gauges seem to be less than that. I looked in the Lyman Black Powder Edition 2 - so p. 268 - for 58 cal - loads listed from 9,300 psi and less, on up to 18,000 psi. So, from that, there are published black powder loads, with conical bullets or ball, that likely exceed the "proof" level pressures used to "proof" a lot of smokeless shotguns with various cartridge lengths and gauges.
And for sure, that Lyman book shows many muzzle loaded BP loads for shot between 1,300 psi (p. 297) and 5,600 psi (305). Gets to be a bit "heavy slogging" between "psi", "CUP" and "LUP" and whether for lead shot or steel shot, and what was used for wads and cards, and which brand of which granulation of black powder, and so on... It might be like loading smokeless shotgun - pressure levels that are "safe" versus where the shotgun comes apart are not apparent to the home guy with no pressure testing gear - just different than the centerfire rifle cartridges that many of us "work up" loads for - there is no "working up" in the very low shotgun pressure ranges.
OP - I re-read your Post #7 - has to be muzzle loading, you want shot, not ball, and want a double barrel. Multiple loads given in that Lyman Black Powder book to do that in a 26" barrel 12 gauge with Modified Choke, but most shot was #7 1/2 through to #2 - I did not think shot size mattered, although weight of the payload does - maybe about getting it to fit?? - and then p. 306 shows using .690" ball in a 12 gauge muzzle loader, with Modified Choke, to max velocity of 1175 fps. No mention that I could find about the forcing cone thing - but for sure many "warnings" about not having "air space" between the black powder and the payload.
And for sure, that Lyman book shows many muzzle loaded BP loads for shot between 1,300 psi (p. 297) and 5,600 psi (305). Gets to be a bit "heavy slogging" between "psi", "CUP" and "LUP" and whether for lead shot or steel shot, and what was used for wads and cards, and which brand of which granulation of black powder, and so on... It might be like loading smokeless shotgun - pressure levels that are "safe" versus where the shotgun comes apart are not apparent to the home guy with no pressure testing gear - just different than the centerfire rifle cartridges that many of us "work up" loads for - there is no "working up" in the very low shotgun pressure ranges.
OP - I re-read your Post #7 - has to be muzzle loading, you want shot, not ball, and want a double barrel. Multiple loads given in that Lyman Black Powder book to do that in a 26" barrel 12 gauge with Modified Choke, but most shot was #7 1/2 through to #2 - I did not think shot size mattered, although weight of the payload does - maybe about getting it to fit?? - and then p. 306 shows using .690" ball in a 12 gauge muzzle loader, with Modified Choke, to max velocity of 1175 fps. No mention that I could find about the forcing cone thing - but for sure many "warnings" about not having "air space" between the black powder and the payload.
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I don't understand how a forcing cone could cause an air space. I am guessing that the transition from chamber to bore could cause a pressure spike to happen.
Unless the concern is the over powder wad not sealing the charge properly because of the difference in diameters when loaded from the muzzle?
Unless the concern is the over powder wad not sealing the charge properly because of the difference in diameters when loaded from the muzzle?
- Location
- Western Manitoba
I have never tried to do so. I notice on the T/C inline that I worked to clean, that the chamber at rear of that in-line barrel for the powder, once that primer plug is threaded in, is smaller diameter than is the bore, not larger than. From the Lyman book, they often show 2 x .125" over powder cards - so would be .250" thick - assuming they are rigid (?) If smaller in diameter to be able to get down bore, would be "too small" further back than the forcing cone, and therefore have "air" around them?
From limited experience loading smokeless powder into shot shell cartridges, easy enough to get all snug and layered, because all going in behind that forcing cone area. With muzzle loader, I suspect is another game, since all that layering and snugness has to be installed through the muzzle? And not fall out, or even move forward, if the muzzle on a loaded shotgun is lowered?
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There is a book called "Recreating the Double Barrel Muzzle-Loading Shotgun". The author builds a nice SXS from old Damascus barrels.
I have used old and modern BP SXS shotguns. All were choked in some way. I size the wad and card to suit, and sometimes bend the card slightly to get it past the choked part, where upon it opens up again as I ram it down.
I agree that modern replicas have generally poor fit. I would not hesitate to buy an old SXS percussion from somewhere like Track of the Wolf. They list condition, cast, balance point, weight, length of trigger pull, etc so you understand what you are getting, and if you buy an old british gun you will find the fit very nice.
Blackpowder is an explosive, with different pressure curves to smokeless powder. Hence using BP only when firing BP proofed guns. I should think modern barrels would be more than adequate, and I think the chokes and forcing cones will not pose a problem if you build the right loads, load properly, check the loads to see they haven't shifted during the hunting day, etc.
I love balanced loads, equal volume powder and shot, keeps life simple. Tremendous fun, though the first bang makes so much smoke that a quick second is impossible...
I have used old and modern BP SXS shotguns. All were choked in some way. I size the wad and card to suit, and sometimes bend the card slightly to get it past the choked part, where upon it opens up again as I ram it down.
I agree that modern replicas have generally poor fit. I would not hesitate to buy an old SXS percussion from somewhere like Track of the Wolf. They list condition, cast, balance point, weight, length of trigger pull, etc so you understand what you are getting, and if you buy an old british gun you will find the fit very nice.
Blackpowder is an explosive, with different pressure curves to smokeless powder. Hence using BP only when firing BP proofed guns. I should think modern barrels would be more than adequate, and I think the chokes and forcing cones will not pose a problem if you build the right loads, load properly, check the loads to see they haven't shifted during the hunting day, etc.
I love balanced loads, equal volume powder and shot, keeps life simple. Tremendous fun, though the first bang makes so much smoke that a quick second is impossible...
Rifles and shotguns are completely different and rifles will always work at higher pressures than shotguns. The larger smooth bore of a 12ga greatly reduces pressures over a smaller diameter rifled barrel pushing a bullet engaged in that rifling at a higher velocity
The area of concern i had was the difference in diameter between the chamber and the forcing cone when using traditional over shot cards and felt wadding and the orientation of getting rigid cards thru the choke. Its easy to open a choke or cut the choke off and on a lesser desirable sxs i have no problem modifying to suit my end goal.
I have several paper wasp nests that i could use for wadding but id prefer a more modern cars and lubed felt wad.
When loading black powder cartridges ill be using over powder and shot cards as i do now for some of my older non nitro proofed guns
The adaptation to muzzleloader is just to get around provincial game laws
The sponsor of the adaptors i use has many videos of loading thru a modified choke and he uses almost anything as wadding and over shot barriers. Since i will be hunting with this setup i want the most consistency possible for known repeatable results and if i cant obtain those well then ill look into a custom double gun built solely as a ml gun. Trying the adapter route first leaves me with a sxs i can still use for other things if my plan fails
The area of concern i had was the difference in diameter between the chamber and the forcing cone when using traditional over shot cards and felt wadding and the orientation of getting rigid cards thru the choke. Its easy to open a choke or cut the choke off and on a lesser desirable sxs i have no problem modifying to suit my end goal.
I have several paper wasp nests that i could use for wadding but id prefer a more modern cars and lubed felt wad.
When loading black powder cartridges ill be using over powder and shot cards as i do now for some of my older non nitro proofed guns
The adaptation to muzzleloader is just to get around provincial game laws
The sponsor of the adaptors i use has many videos of loading thru a modified choke and he uses almost anything as wadding and over shot barriers. Since i will be hunting with this setup i want the most consistency possible for known repeatable results and if i cant obtain those well then ill look into a custom double gun built solely as a ml gun. Trying the adapter route first leaves me with a sxs i can still use for other things if my plan fails
There is a kit ( US side...) that can be used in a standard shotgun 12,20,etc. They call it a “ muzzle loader conversion “ plug. But really it’s just a very heavy wall shotgun shell/case, that you reload as you would a standard shell, buckshot, slug... what ever . Or you can load them from the muzzle end, the old fashion way...they take a 209 primer.
You can buy a couple of them and keep a couple in your pocket, along with your reloading “ muzzle loading supplies” .
I’ve never used one and only would in a “ normal” uses 12 gauge shell circumstance . But there are probably a lot of people out there using them, as muzzle loader adapters!
Cheers
Brian
You can buy a couple of them and keep a couple in your pocket, along with your reloading “ muzzle loading supplies” .
I’ve never used one and only would in a “ normal” uses 12 gauge shell circumstance . But there are probably a lot of people out there using them, as muzzle loader adapters!
Cheers
Brian
gunsaholic
CGN Ultra frequent flyer
- Location
- Winnipeg, Manitoba
I have a muzzleloading double barrel that has had a set of breech loading barrels fit to it. Whoever did it went to a lot of work. I'm guessing something happened to the original barrels.
