First build:Back action lock drum support

[Hank]

Hi. New guy. I've been lurking here for a few months and have learned more than I'll be able to remember.
This my first build and I need some advice. It's a halfstock with a 36 inch Colerain, 13/16, 45 cal. barrel. The stock is from TOW and is semi inletted for the barrel and has the large wood pads for a front action lock. I've fitted the long tang, 5/8 breech plug; good contact on the inside shoulder and the end of the barrel. The writing is on the bottom flat per the guys at Colerain. I used the whole 5/8 long threaded length of the plug, retaining the polished face it came with. I'm using a 7/16 drum with a 5/16x24 thread. I plan to drill and tap into the barrel and plug so 2/3 to 3/4 of the drum threads are tapped into the end of the plug. I'll open up the exposed side of the drum threads in the face of the plug.
Now, here we go.  I can visualize how a hammer beating on the nipple in that drum in the side of that skinny barrel could eventually, if not sooner, bend,break or at least loosen the drum threads. So I'm trying to figure out how to support the drum the way a front action lock would.
I've thought of welding a support on the front end of the L&R lock. Or, leaving the wood around the drum at full thickness and making a brass or steel insert that would form fit over the wood and under the drum and be bolted through to the side plate, like a front lock bolt. I'll make a side plate for three bolts.
What I get for wanting a light gun.
I've looked at all the pictures I could find of old drum-and-back-action-lock guns. I'd say they mostly have heavier barrels so the support is there in the barrel.
I'd be grateful for any advice or ideas any of you might have.

[T*O*F]

Take a look at a Philadelphia Derringer.  While they have a patent breech, there is no reason why you cannot make an inlay which mates with your lock and also supports the drum.

http://www.bing.com/images/search?q=philadelphia+derringer&FORM=HDRSC2#view=detail&id=853D26E2A2A81E31347B7AA9F8C2707A9C434436&selectedIndex=107

[Hank]

Excellent! Great pictures. Close to what I was imagining I'd need but better looking. One of the locks was shown off the gun and the "inlay" was part of the lock. That's the way to go. I'll weld the "inlay" to the lock and make it look good with a nice shape and help it along with a third bolt between the rod and barrel.
Thank you T*O*F

[curly]

If I were you, I'd check out that wall thickness. 5/16- 24 on a 11/16 barrel is very thin. Wouldn't want any see any blow outs down the road, IMHO.
Curly

[Pete G.]

TOW has a patent breech that is similar in shape to a drum. Works well with the back action lock and is much stronger than any drum setup ever can be.

[Hank]

If I were you, I'd check out that wall thickness. 5/16- 24 on a 11/16 barrel is very thin. Wouldn't want any see any blow outs down the road, IMHO.
Curly

I know. A little scary. I figure by keeping  the drum threaded into the plug as well it would pretty much prevent a blowout as long as I can keep the whole thing tight and secure. I thought of drilling a hole in the center of the plug face and keeping ALL of the drum threads in the plug but then I've got two ninety degree turns. Still a fairly short run but not as quick as the drum just through the barrel wall.
 

TOW has a patent breech that is similar in shape to a drum. Works well with the back action lock and is much stronger than any drum setup ever can be.

Aha! I also have that breech plug with the cast in drum. Got it in case I chickened on the plain drum but it has such a long run and just doesn't give me the look I want.
I'll figure it out. If the drum gets well supported I'll be safe and happy. If I don't feel comfortable with it I'll cut it off and fit the other plug and weld the long tang onto it.
I have a counter bore I made for the inside shoulder and a tap I ground into a bottom tap that helps cut the shoulder, sort of, so between the two tools I can cut a new journal
in a couple hours.
Hank

[Hungry Horse]

Hank;

  While I understand, and agree, with some of the others on this forum in regards to the drum, and nipple, systems short comings. The most important reason for supporting the drum"WITH THE LEADING EDGE OF THE LOCKPLATE" on a back action lock, is to keep the lock from moving upward, and breaking the stock. If the only limiting force that prevents this upward movement is the lock bolt, the stock will be broken eventually. I have seen several antiques with this problem. Even if the lock bolt passes through the tail of the breech plug, wear, and time, will eventually do damage to an unsupported lock.

                       Hungry Horse

[Dphariss]

If I were you, I'd check out that wall thickness. 5/16- 24 on a 11/16 barrel is very thin. Wouldn't want any see any blow outs down the road, IMHO.
Curly

I know. A little scary. I figure by keeping  the drum threaded into the plug as well it would pretty much prevent a blowout as long as I can keep the whole thing tight and secure. I thought of drilling a hole in the center of the plug face and keeping ALL of the drum threads in the plug but then I've got two ninety degree turns. Still a fairly short run but not as quick as the drum just through the barrel wall.
 

TOW has a patent breech that is similar in shape to a drum. Works well with the back action lock and is much stronger than any drum setup ever can be.

Aha! I also have that breech plug with the cast in drum. Got it in case I chickened on the plain drum but it has such a long run and just doesn't give me the look I want.
I'll figure it out. If the drum gets well supported I'll be safe and happy. If I don't feel comfortable with it I'll cut it off and fit the other plug and weld the long tang onto it.
I have a counter bore I made for the inside shoulder and a tap I ground into a bottom tap that helps cut the shoulder, sort of, so between the two tools I can cut a new journal
in a couple hours.
Hank

The the problem is the cold rolled drum BREAKING OFF flush with the barrel. They HAVE to be supported. I would have used a patent breech. Far, far safer. Regardless of their use in the past drum and nipples are a very poor design on all counts. Also remember that the original drums were made of material with much better shock resistance than the modern versions. The originals would simply bend. With a sharp shouldered cut and the threads a cold rolled drum is almost designed to break when shock loaded.

Stocks that are broken out above the front of the lock plate are the result of inletting errors that weaken the wood then it breaks in service of before the gun is even completed. I have done this and having the lock "supported" by the patent breech did not prevent it.

Dan

[Hank]

Thanks for all the advice. I'm going to play it safe and use the slant faced Hawken hooked plug from TOW (LR-15-5, Long tang and easy to clean) and I guess I'll forget the back action and use the matching LR-150 lock. This gun is for hunting and besides wanting it to be light as possible I want it strong and dependable. The drum strength has always been an issue with me so that tells me something.
This is a minie ball gun. Gain twist to 1 in 32 for a 300 grain HB bullet. I've hunted with original Winchester 1885s for so long I guess I'm having a hard time getting away from the long conical.
Full stock flint gun is next. No caps to buy. No leading. Almost self-sustaining.
With the 400 hundred pounds of lead in the barn, the 50 pounds of BP in the cellar ( I will have to get some ffff?)  and a bag full of flints, I could hunt forever right out the back door.

Can you make BP out of horse manure? I'd never have to leave the property.

[Bob Roller]

 4fg? For what? I have always loaded and primed from the same horn or flask
and there is NO difference in ignition time that I could see or notice.

Bob Roller

[Dphariss]

Thanks for all the advice. I'm going to play it safe and use the slant faced Hawken hooked plug from TOW (LR-15-5, Long tang and easy to clean) and I guess I'll forget the back action and use the matching LR-150 lock. This gun is for hunting and besides wanting it to be light as possible I want it strong and dependable. The drum strength has always been an issue with me so that tells me something.
This is a minie ball gun. Gain twist to 1 in 32 for a 300 grain HB bullet. I've hunted with original Winchester 1885s for so long I guess I'm having a hard time getting away from the long conical.
Full stock flint gun is next. No caps to buy. No leading. Almost self-sustaining.
With the 400 hundred pounds of lead in the barn, the 50 pounds of BP in the cellar ( I will have to get some ffff?)  and a bag full of flints, I could hunt forever right out the back door.

Can you make BP out of horse manure? I'd never have to leave the property.

If I want to shoot a conical I shoot a modern or a BPCR. Trust me there is no real difference is killing power between a BPCR and a suitable sized RB unless shooter well past 100 yards.

Having hunted with BPCRs from 38-40 to 450 BP Express and 50 through 75 caliber RBs I can assure you this is true. In fact if anything at most hunting ranges a  
The problems and dangers associated with conicals in MLs outweigh their supposed superiority.
Nor are the modern conicals a traditional ML hunting projectiles.

Dan