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Miroku Brown Bess; Busted

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Rundownfid

32 Cal
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I recently purchased a Miroku Brown Bess originally sold by Dixie Gun Works. It is, or was, a good sparker and seemed a great purchase. However, the mainspring broke and it appears that there are no replacement parts available? I did find a spring at Track of the Wolf that they said could be made to fit, which I have ordered. Any advice on this issue?

Also, there is no sling provision, neither the trigger guard nor the forearm sling swivel is present,not even drilled so a replacement could be fitted. Any suggestions for this issue?

I'd like to get this musket firing accurately as possible, with an eye to the occasional trail walk match. It shoots reasonably well out to 50 yds. Not as accurately as my 3-gun shotgun with slugs, probably because there is no rear sight? Thoughts on making it more accurate, while still being within the spirit of a smooth bore musket?
 
Have you contacted Dixie? One used to be able to send them a lock and they would find a spring to match it in their stuff. I would make or get a rear sight I could solder or epoxy on, so it could be removed later. You will probably have to silver solder a lug on the forward part of the barrel and inlet it into your stock and drill it for a swivel; alternatively you could fit a band and swivel to the exposed part of your barrel and rig a button type sling stud to the underside of the buttstock. You have a good all around ball and shot gun, good luck with your project; let us know what you do! Geo.
 
I had two of them, I carefuly drilled the trigger bow and one of the barrel tenons for sling swivels
 
You’ll need a new mainspring with a blind lug to fit. I’ve used Springfield mainsprings casted by Butch’s Antique Gun Shop and fitted to my Charleville.

For the Sling Swivel, you would solder about 1 inch ahead of the second rammer pipe, then cut the lug into the stock, measure and drill.
 
Mike Lea, who advertises in Muzzle Blasts actually makes parts for odd Besses. Springs and Frizzens. Give him a call.
 
I recently purchased a Miroku Brown Bess originally sold by Dixie Gun Works. It is, or was, a good sparker and seemed a great purchase. However, the mainspring broke and it appears that there are no replacement parts available? I did find a spring at Track of the Wolf that they said could be made to fit, which I have ordered. Any advice on this issue?

Also, there is no sling provision, neither the trigger guard nor the forearm sling swivel is present,not even drilled so a replacement could be fitted. Any suggestions for this issue?

As a matter-of-fact, I was handed a Miroku Bess lock yesterday with a broken mainspring. Oh well it was only 50 years old. ;)
The replacement mainsprings for Pedersoli Bess locks often may be "fit" to the Miroku locks. The problem normally is..., (I write "normally" as we are talking after-market springs, not Pedersoli springs) ….the lug on the side of the mainspring will not quite go into the hole in the lock plate where it belongs, when the spring is aligned with the mainspring screw hole. Once that lug has been "thinned" and the spring will "fit" so that the lug goes into the lock plate when the mainspring screw is installed, THEN you have to check the TOE of the spring.
MAINSPRING.JPG

So the toe on the aftermarket springs tends to interfere with the internal tumbler, and can jam it. In the photo the toe is correct, but in the after-market springs it often hits in the red area......
BESS LOCK SPRING TOE 1.jpg

So you may have to remove some of the toe to get it so it does not jam the tumbler, BUT you have to also be careful NOT to remove too much of the toe as it must still rest upon the tumbler when the lock is fully down, in the uncocked position. The lock below is precariously close to the spring coming off the tumbler...

BESS LOCK OPEN 2.JPG


As for the sling... You have to drill the trigger guard at the front of the bow, and the upper swivel sometimes works when you enlarge one of the barrel lug holes, BUT be careful..the upper sling swivel should NOT rest on the actual ramrod when installed, but must come down against one of the ramrod thimbles. Otherwise the sling will jam up the ramrod.


LD
 
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Just a thought - you have a very early Miroku Bess. The flattened triggerguard was never changed but the lack of sling swivels was corrected very early on. Thought I'd mention it.
 
Excellent answers, looks like I have some gunsmith to do or get done. thanks everyone who answered, I'll undoubtedly have more questions as I get further into the process.
 
So you may have to remove some of the toe to get it so it does not jam the tumbler, BUT you have to also be careful NOT to remove too much of the toe as it must still rest upon the tumbler when the lock is fully down, in the uncocked position. The lock below is precariously close to the spring coming off the tumbler...

View attachment 23887

LD

LD,

This was a great explanation of some things one runs into when fitting a different or after market spring to locks.

I especially like the last photo because it shows what I ran into when fitting a Dixie replacement main spring to an original Waters and Johnson Flintlock pistol. Dixie has them made or the supplier/s make the springs with oversized rectangles of metal so one can file them down for the lug to fit correctly in the original hole and the toe fit correctly on the tumbler. This because the lug holes in the lock plates, made prior to the Interchangeable Parts System, can vary a good deal as to the location of the holes.

However, on the original lock plate I was working on and after compressing the spring a number of times to check fit, I wasn't sure if the rectangle of metal would allow me to file the lug and the toe still stay on top of the Tumbler and not slip off. It was real "touch and go," but it BARELY allowed me to file the lug and the toe fit on top of the Tumbler and not be too short.

Of course I never learned how to make mainsprings, so I was EXTREMELY glad I did not have to heat the curved toe and flatten it a bit to get more length so the toe would stay on the Tumbler, then re-heat treat it afterwards.

Gus

P.S. Years ago, I purchased some original M1842 main springs and sear springs. It took a few years before I realized they sometimes can be fitted to repro Brown Bess locks and when you can, WOW does it give a lot of "oomph" to make the Cock fly forward with a good deal of speed and force.

Gus
 
Well I learned the "hard way" by doing a FUBAR on several main springs before a kindly gunsmith showed me what was going wrong.

Right now I have a quandary. IF I can't find a good spring to fit a Jap bess lock that I was given last Sunday, then I have to fit the after market replacement spring for a Pedersoli to the lock which the lock owner provided.

When the lug on the spring is in its hole, the spring is almost a good fit, with the toe just a teeny bit long, BUT the loop in the main spring for the main spring screw is 50% off..., yet the loop for the screw DOES fit up into the groove on the underside of the interior ledge of the pan.

When the screw loop is aligned with the screw hole, the lug is too far off from its hole to be used, and the spring is a bit too long to adjust and fit. I could..., simply fill the main spring screw hole with a cut off portion of a screw, and let the groove on the inside ledge of the pan do the work, but it wasn't designed like that for a reason.

The other option would be to fill the present main spring screw hole with a bit of screw shank and silver solder it...or maybe have a buddy who is a welder, weld it closed....then drill and tap a new main spring screw hole, thus modifying the lock to take after market Pedersoli lock main springs in the future, if needed. I hesitate to do that. :confused:

LD
 
Well I learned the "hard way" by doing a FUBAR on several main springs before a kindly gunsmith showed me what was going wrong.

Right now I have a quandary. IF I can't find a good spring to fit a Jap bess lock that I was given last Sunday, then I have to fit the after market replacement spring for a Pedersoli to the lock which the lock owner provided.

When the lug on the spring is in its hole, the spring is almost a good fit, with the toe just a teeny bit long, BUT the loop in the main spring for the main spring screw is 50% off..., yet the loop for the screw DOES fit up into the groove on the underside of the interior ledge of the pan.

When the screw loop is aligned with the screw hole, the lug is too far off from its hole to be used, and the spring is a bit too long to adjust and fit. I could..., simply fill the main spring screw hole with a cut off portion of a screw, and let the groove on the inside ledge of the pan do the work, but it wasn't designed like that for a reason.

The other option would be to fill the present main spring screw hole with a bit of screw shank and silver solder it...or maybe have a buddy who is a welder, weld it closed....then drill and tap a new main spring screw hole, thus modifying the lock to take after market Pedersoli lock main springs in the future, if needed. I hesitate to do that. :confused:

LD

Ive never had to replace a miruko spring, their springs are usually too strong, so strong they’ve busted a few stocks.

I’ve replaced pedersoli springs with casted Springfield M1816 and M1842 springs, they actually work much better.

The issue with pederoli springs I’ve always had was the frizzen spring on the 1766 Charleville, its not authentic looking at all and to add, is pretty weak, I’ve worked with 2 different springs on it but the only other option I have to is relocate teh screw hole
 
The other option would be to fill the present main spring screw hole with a bit of screw shank and silver solder it...or maybe have a buddy who is a welder, weld it closed....then drill and tap a new main spring screw hole, thus modifying the lock to take after market Pedersoli lock main springs in the future, if needed. I hesitate to do that. :confused:

LD

Dave,

Have you tried Ackermann Arms to see if they have a direct replacement for the Miroku main spring? Personally, I would try that first before the time and expense of altering the lock plate and yes, even though a Pedersoli spring was provided to you. Someone else can always use the Pedersoli spring in their Pedersoli musket.

https://www.ackermannarms.com/

If that is not possible, then IMO the next best thing is to alter the lock plate (if needed) for a main spring that will be "around and available for quite a while" (whether an original or repro main spring) in case the replacement is used so much it also breaks and the owner needs another replacement.

For a change, Dixie offers an original M1842 mainspring for an advertised price of only $ 30.00 and originals are already hardened and tempered. If one feels their strength is too much, one can file or carefully grind then file the chamfered edges more to reduce the spring tension. However and if you have to modify the lock plate for this mainspring, these springs will be around for quite a while.
https://www.dixiegunworks.com/index...g+(Original)+For+U.S.+1842+Springfield+Musket

I don't have experience with the "casted" main springs FlinterNick mentioned. If they are already hardened and tempered and from a company that will be around a while, that may be a good choice as well.

IOW, what I'm proposing is lock plate alterations (if needed) for a main spring that would or may be readily available to be fitted/replaced in an urgent situation, such as at a reenactment or competition. As a NM modern Armorer, an Armorer who worked for many years at NSSA National Competition and as the Team Armourer for the US International Muzzleloading Team to two World Championships - I have seen the importance of this time and time again.

Gus
 
Dave,

Have you tried Ackermann Arms to see if they have a direct replacement for the Miroku main spring? Personally, I would try that first before the time and expense of altering the lock plate and yes, even though a Pedersoli spring was provided to you. Someone else can always use the Pedersoli spring in their Pedersoli musket.

https://www.ackermannarms.com/

If that is not possible, then IMO the next best thing is to alter the lock plate (if needed) for a main spring that will be "around and available for quite a while" (whether an original or repro main spring) in case the replacement is used so much it also breaks and the owner needs another replacement.

For a change, Dixie offers an original M1842 mainspring for an advertised price of only $ 30.00 and originals are already hardened and tempered. If one feels their strength is too much, one can file or carefully grind then file the chamfered edges more to reduce the spring tension. However and if you have to modify the lock plate for this mainspring, these springs will be around for quite a while.
https://www.dixiegunworks.com/index/page/product/product_id/6239/category_id/451/product_name/TP0623++Mainspring+(Original)+For+U.S.+1842+Springfield+Musket

I don't have experience with the "casted" main springs FlinterNick mentioned. If they are already hardened and tempered and from a company that will be around a while, that may be a good choice as well.

IOW, what I'm proposing is lock plate alterations (if needed) for a main spring that would or may be readily available to be fitted/replaced in an urgent situation, such as at a reenactment or competition. As a NM modern Armorer, an Armorer who worked for many years at NSSA National Competition and as the Team Armourer for the US International Muzzleloading Team to two World Championships - I have seen the importance of this time and time again.

Working with a hardened and tempered spring is difficult and easy to mess up.

Its much easier working with a raw casted spring that isn’t hardened because you easily file it and polish it to fit the specifications. It just has to have a large integral lug.

Once its fitted then, heath with a MAP torch quench a few times until its hardened and then timber at around 700-900 degrees. I put mine on the kitchen stove to temper, once I get the colors I want, its complete.

Nick
 
Working with a hardened and tempered spring is difficult and easy to mess up.

Its much easier working with a raw casted spring that isn’t hardened because you easily file it and polish it to fit the specifications. It just has to have a large integral lug.

Once its fitted then, heat with a MAP torch quench,
a few times until its hardened and then temper at around 700-900 degrees. I put mine on the kitchen stove to temper, once I get the colors I want, its complete.

Nick
 
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Yes I'm having Ackerman arms look for some parts as well as a mainspring.
I will also look at M1842 rifle springs.
I have taken cast springs in the past and they have worked well, but only for frizzen springs, not main springs, so I'd prefer to use a factory finished main spring due to the much harder use on that spring.
I agree, if it's needed, that altering a the lock to a much more readily available main spring is a good option, although better would be one that either could be fit, or one that dropped in, eh?

LD
 
Yes I'm having Ackerman arms look for some parts as well as a mainspring.
I will also look at M1842 rifle springs.
I have taken cast springs in the past and they have worked well, but only for frizzen springs, not main springs, so I'd prefer to use a factory finished main spring due to the much harder use on that spring.
I agree, if it's needed, that altering a the lock to a much more readily available main spring is a good option, although better would be one that either could be fit, or one that dropped in, eh?

LD

As long as the plate is around 6 1/4 - 6 1/2 inches long the 1842 spring should be a little larger. I took down the foot filled back the loop and post and look about about 1 1/100 of a mm of the plate side. The TOW Wilets lock mainspring is too large.
 

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As long as the plate is around 6 1/4 - 6 1/2 inches long the 1842 spring should be a little larger. I took down the foot filled back the loop and post and look about about 1 1/100 of a mm of the plate side. The TOW Wilets lock mainspring is too large.
WOW that was super kind of you to go to all that trouble and photographs and even a scale next to the spring. Can't thank you enough!!!

LD
 
Ive never had to replace a miruko spring, their springs are usually too strong, so strong they’ve busted a few stocks.

I’ve replaced pedersoli springs with casted Springfield M1816 and M1842 springs, they actually work much better.

The issue with pederoli springs I’ve always had was the frizzen spring on the 1766 Charleville, its not authentic looking at all and to add, is pretty weak, I’ve worked with 2 different springs on it but the only other option I have to is relocate teh screw hole
I've heard of "stitch counters", those who pick at every little detail, but who on Earth is going to notice a frizzen spring is not authentic? Other than a specialist musket expert. Not being a wise guy, just commenting. Thanks.
 
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