Copy of an original blunderbuss

[davec2]

I will need to proof this barrel before I go too far with the build. It is a 7 bore. It's made out of better material than the original (I'm fairly sure) and the bore is slightly smaller (i.e. thicker walls), so it should be fine. However, anyone know what a 7 bore proof charge should be ?


#@!! $#@* !!!! Just found the British Gun Barrel Proof Act of 1868.......here is an excerpt ......





For a 7 bore, look at the powder and projectile weights required for a first and second proof !!!!!! I want to proof the barrel but this looks more like I'm making a pipe bomb !!!

I found an old chart in a 1972 Dixie Gun Works catalog that had some Belgian service and proof charges. The service charge was 158 grains behind a 7 gage round ball but the proof charge was over 500 grains !!! I like the idea of perhaps 180 to 200 grains as the proof charge behind 3 oz of shot for the first proof. Less powder and a little more shot for the second. The barrel is only 12 inches long, so I really don't want to fill it half way with powder and then a load of shot ....I could be inadvertently testing that old black powder BS about "oh you can fill the whole barrel with powder and it would still be fine !"

 

[davec2]

I found an old chart in a 1972 Dixie Gun Works catalog that had some Belgian service and proof charges. The service charge was 158 grains behind a 7 gage round ball but the proof charge was over 500 grains !!! I like the idea of perhaps 180 to 200 grains as the proof charge behind 3 oz of shot for the first proof. Less powder and a little more shot for the second. The barrel is only 12 inches long, so I really don't want to fill it half way with powder and then a load of shot ....I could be inadvertently testing that old black powder BS about "oh you can fill the whole barrel with powder and it would still be fine !"

Just for fun I put 600 grains of FFg in the bore. It filled the 7 bore (0.875 in this case) between the two blue tape marks....i.e. the brass showing between the two pieces of tape is the length of the bore filled with 600 grains of powder. Looks a little excessive to me.....but what do I know ???

 

[jstroke]

This is just fantastic! Looking forward to the proofing results.

 

[davec2]

This is just fantastic! Looking forward to the proofing results.

I’ll post a video Should be fun

 

[jstroke]

I’ll post a video Should be fun

I was hoping you’d say that!

 

[Pete G]

I don’t like exposing a gun to excessively high pressures just to see if it will fail. A double load seems to be adequate.

 

[davec2]

Pete,

I agree with you.

 

[Brokennock]

Just for fun I put 600 grains of FFg in the bore. It filled the 7 bore (0.875 in this case) between the two blue tape marks....i.e. the brass showing between the two pieces of tape is the length of the bore filled with 600 grains of powder. Looks a little excessive to me.....but what do I know ???

I would think it would be spitting shot and powder out the muzzle before the entire charge gas burned, just based on proximity of the front of the charge to the muzzle...
But, I'm probably wrong and someone will be along shortly to tell me so and, hopefully, why.

 

[PathfinderNC]

Dave- Pleaseeee be careful and use a very long fuse

(Wait- don’t you test out rocket engines ? )

 

[davec2]

Pathfinder,
Yes…..I test rocket engines for a living…. So I will fire this barrel electrically from a safe distance….

Brokennock,
I think you are correct that a lot of the powder charge would burn in the air outside of the barrel. We will see.

 

[Brokennock]

Pathfinder,
Yes…..I test rocket engines for a living…. So I will fire this barrel electrically from a safe distance….

Brokennock,
I think you are correct that a lot of the powder charge would burn in the air outside of the barrel. We will see.

Video? PLEASE!!!!!!

 

[Tejano Libre]

Gathering parts that are close to the original. Here is the original lock compared to one of Chamber's English fowler locks.....



Some options for the trigger guard.......







The guard with the acorn finial is a little too big in the bow and the bow is too narrow. I will go with the trigger guard with the fancier finial just for the size and shape of the bow.

This butt plate can be easily modified to almost exactly match the original....



This side plate is very close to the original but I may just duplicate the original by making a silicone mold and then doing a centrifugal casting in brass....



Rounded up the brass bar stock for the barrel. Got it set up in the lathe and started the pilot hole through. The bore will be about a 7 gage when finished.....

Howdy Amigo,
How are you doing today? Fair to Partly Midland at least? I sincerely hope so. Please pardon me if I have already asked you this question because I don't know how to use this Forum and unfortunately I am having to use my Television's browser! Anyway, I was wondering if you would be willing to "cast" a Brass Patch Cover for my Belgian DAG 1850's Blunderbuss?
Or if you can please recommend someone or a source for replacement or replica parts? It's seashell or conch shaped and hinged if you are familiar with that type?
Thank you kindly,
Tejano Libre

 

[davec2]

I had a little time between business trips to look at the barrel again and make some decisions about proof testing. The first thing I realized is that I didn't really like the profile of the new barrel. I had taken the easy way out and, in cutting the outside taper, I had just used the compound on the lathe. The travel is only about 4 inches on my compound so I had to cut the full length taper in three sections. Then I cleaned up the surface with a lathe file and then various grits of abrasive paper. The result was OK but after closer inspection is was a little...well....lumpy. You can't really see it with the naked eye, but I could feel it running my fingers over the surface. It bothered me so much that I decided to recut the taper. And if I was going to take off more metal, I should do that first before I did the proof firing. So I re-cut the taper properly. I took the time to calculate the offset required on the tail stock, off set it, and then ran the taper cut in one pass with the cross slide in auto feed. Came out great and feels right now... (The hard part here is getting the tail stock back on center....not really hard, just time consuming.) As soon as I get back from my next short trip I will build a test fixture and take the barrel out to my test site to run the proof firings.

 

[davec2]

Howdy Amigo,
How are you doing today? Fair to Partly Midland at least? I sincerely hope so. Please pardon me if I have already asked you this question because I don't know how to use this Forum and unfortunately I am having to use my Television's browser! Anyway, I was wondering if you would be willing to "cast" a Brass Patch Cover for my Belgian DAG 1850's Blunderbuss?
Or if you can please recommend someone or a source for replacement or replica parts? It's seashell or conch shaped and hinged if you are familiar with that type?
Thank you kindly,
Tejano Libre

Tejano.......sorry I missed seeing your question. Can you send me any kind of a picture of the part you are missing ?