Building and Engraving a .375 double barrel rifle

[highveldt]

A couple of months back I began work on my 2015-16 Winter project. It has been slow go as this is the first time I have built as set of double rifle barrels using the "shoe lump" method. This method is used by the likes of German, Austrian and French rifle makers to name a few. The method is uncommon in the USA and UK, and it is not for the faint of heart, under-experienced craftsman without a significant machine shop.

I will attach a few photos of the work to date. However, to provide you with an idea of how much work goes into the machining and fitting of the shoe lump, let me say that the second photo shows a 2.0" diameter by 2.6" length round bar of 4140 chrome moly alloy steel weighing 2 lbs. This bar of 4140 alloy steel will be machined to produce the final shoe lump that will be 2.6" long and will weigh 4 ounces--as the photos show. This lump will be fitted to the two barrels and brazed to them at 1280 degrees F in a gas fired muffel.

The last photo shows the barrel in the jig/clamp ready to take to the furnace for brazing together. I hope to do this tomorrow.

 

[thughes]

Wow, that's very interesting, thanks for the photos.

Todf

 

[Tim Wells]

Nice machine work, looks like you have a nice rigid mill judging by the finish.

 

[Roger Bleile]

This is real gunsmithing! There is nothing more difficult for a gunmaker than building a well regulated double rifle. I look forward to seeing your progress.

RB

 

[jerrywh]

If you are placing the whole barrels in the furnace I assume that they will remain in the annealed state. How do you bed them to prevent warping. I have done double shotgun brazed barrels but never a double rifle. I would love to talk to you on the side about the oxidization problems.

 

[highveldt]

Jerry;

Send me a PM with your e-mail address and I will answer all your questions.

Steve

 

[monk]

you are a very brave man. that's really an exceptional project to take on. do you bore out the barrels yourself ? i am curious to know how you can tell in advance, if the 2 will put a round in the same impact area that the gun is aimed at. is there a formula to determine that ? thanks very much for taking the time to show such a project.

 

[highveldt]

you are a very brave man. that's really an exceptional project to take on. do you bore out the barrels yourself ? i am curious to know how you can tell in advance, if the 2 will put a round in the same impact area that the gun is aimed at. is there a formula to determine that ? thanks very much for taking the time to show such a project.

Monk;

I leave the barrel boring and rifling to the barrel blank makers and I receive a blank 1.2" inches in diameter 27 inches long, that I hand cut the outside barrel profile to the style I desire.

I do not know how the barrels will shoot in relationship to each other until I begin test firing (after I proof test the barrels first with a 20% overload charge). However, I try to contour my barrels as perfect to each other in diameter and weight as I can, hoping that this will help each barrel to oscillate and flex the same during firing.

 

[monk]

Monk;

I leave the barrel boring and rifling to the barrel blank makers and I receive a blank 1.2" inches in diameter 27 inches long, that I hand cut the outside barrel profile to the style I desire.

I do not know how the barrels will shoot in relationship to each other until I begin test firing (after I proof test the barrels first with a 20% overload charge). However, I try to contour my barrels as perfect to each other in diameter and weight as I can, hoping that this will help each barrel to oscillate and flex the same during firing.

thanks. as i said, a very brave undertaking !.

 

[Glenn]

Wow! You and I could spend many hours talking about building double rifles. I've just finished a double 577 Nitro. Ready now to start the final wood filing, sanding then finish.
I have a 460 Weatherby with the barrels epoxied into a double shotgun. This has not been shot yet leave alone regulating. I bought this as is.
I have a double 7mm rimmed Ackley Improved. I threaded the barrels into a 4140 breach block machined to fit a 16ga German Greener cross bolt action
Conclusion: If you ever start thinking you are going a little crazy, remember this crazy guy.

 

[SamW]

Nothing wrong with being crazy Glen...just don't tell anyone!

 

[silverchip]

I really like watching your progress in this endevour, anxious to see more!!!

 

[DKanger]

I do not know how the barrels will shoot in relationship to each other until I begin test firing

I am curious about your philosophy for regulating barrels. It's an often hotly contested subject, with many maintaining that the projectiles should cross at a specified distance. I think this is fine for a purpose built, choked shotgun where the type of game being shot would determine that distance; ie, quail, pheasant, ducks, geese, etc.

However, I maintain that a double rifle should shoot both barrels parallel with the projectiles hitting side by side. This might not be required for a large bore shooting dangerous game up close. However, many rifles are equipted with express sights, often out to 400 yards for shooting plains ungulates. If the trajectories crossed, the rifle would only be accurate to the apex of the X and anything beyond would be sailing off into neverland.

What are your thoughts?

I am currently acquiring parts for a muzzleloading combination gun, one barrel rifled and the other smooth. Bob Roller is building me a pair of locks with overlapping sears, so either barrel can be fired with a single trigger, depending on which one is cocked. Afield, this allows one to selectively choose which barrel to use if game or fowl are encountered.

 

[highveldt]

I am curious about your philosophy for regulating barrels. It's an often hotly contested subject, with many maintaining that the projectiles should cross at a specified distance. I think this is fine for a purpose built, choked shotgun where the type of game being shot would determine that distance; ie, quail, pheasant, ducks, geese, etc.

However, I maintain that a double rifle should shoot both barrels parallel with the projectiles hitting side by side. This might not be required for a large bore shooting dangerous game up close. However, many rifles are equipted with express sights, often out to 400 yards for shooting plains ungulates. If the trajectories crossed, the rifle would only be accurate to the apex of the X and anything beyond would be sailing off into neverland.

What are your thoughts?

I am currently acquiring parts for a muzzleloading combination gun, one barrel rifled and the other smooth. Bob Roller is building me a pair of locks with overlapping sears, so either barrel can be fired with a single trigger, depending on which one is cocked. Afield, this allows one to selectively choose which barrel to use if game or fowl are encountered.

I agree with your thoughts as do Holland & Holland and other professionals. Further the rifle builder should spend the time regulating the barrels using a selected projectile speed and weight so that the DR will place the two shots, with cold barrels at 50 and 100 yards the same distance apart as possible.

I post below photos of my 20 bore sabot express DR that was regulated for Rem Accutip 260 grain projectiles, however, it will shoot Hornady's and other slower well. The faster the projectile the better the accuracy.

I have been very much surprised in all the interest in building double rifles exhibited by members of "Engravers Cafe" responding to this post and in addition to the posts here I have a number of PMs. When I made the original post I did it on a slow day for the BBS and thought it might make interesting reading for that day. I am reluctant to follow-up with more photos an comments in the process of completing this rifle as the subject matter is very short on engraving until at the end, and it is a bit or maybe a lot off of the intent of Engravers Cafe. I suppose I should send Sam an e-mail and ask him what I should do.

 

[silverchip]

I am reluctant to follow-up with more photos an comments in the process of completing this rifle as the subject matter is very short on engraving until at the end, and it is a bit or maybe a lot off of the intent of Engravers Cafe.

Gotta have a canvas before you and paint. Post away!!!

 

[Marrinan]

As I recall we had another case study some years ago and it was followed with great interest and participating. Hand info on the wedging of barrels and methods of soldering the ribs down the barrel as I recall. I am also interested in learning more about how you do it. Fred

 

[highveldt]

Thanks for the interest in this time consuming task I have taken on. I have made more progress and have begun jointing the barrels to the action. Brazing of the barrels together makes them look as if they are forever ruined. Here are some photos that show the before brazing, after brazing just from the furnace, after clean up from furnace, and machining the hidden third fastner at the breech end of the barrels

 

[D Smith]

Please if you would do me one favor? Could you take a pic of the caliper on the side of the quill on your mill? I need to do this to mine. I also need to make an adjustable square like to one setting on the parallel on your vice.
Fantastic machining! Yesterday I made the mandrel to hold my diamond disc for my drill press to help sharpen my graver's. Small potatoes to what your doing. But it takes tooling to make tools to help me engrave.

Please keep the pic's coming, I cant wait to see you make the rib!

D Smith

 

[highveldt]

Please if you would do me one favor? Could you take a pic of the caliper on the side of the quill on your mill? I need to do this to mine. I also need to make an adjustable square like to one setting on the parallel on your vice.
Fantastic machining! Yesterday I made the mandrel to hold my diamond disc for my drill press to help sharpen my graver's. Small potatoes to what your doing. But it takes tooling to make tools to help me engrave.

Please keep the pic's coming, I cant wait to see you make the rib!

D Smith

Mr. Smith;

Send me a PM with your e-mail and I will make you photos of the quill caliper and the adjustable square and send them to you. The quill caliper is really handy--and inexpensive.

 

[highveldt]

More Photos.

I have made more progress on the double rifle building and should be able to make the extractors next week and then proof test the barrels. The barrels have been preliminary fitted to the action as well as the fore-iron frame. I have built the fore-end iron loop as well as the middle barrel brace which will also serve as the forward sling swivel support. These two items were silver brazed to the barrel set.

I have to decide the minimum amount of engraving that I can do on the action because of its hardness. I may need to find a mini plasma torch to engrave with-- jesting, of course but not that much.