Is this breech plug safe to use?

[Scota4570]

https://www.dropbox.com/sh/8qsi2tqrf4fqgv6/AAB5oigMHp9FhweY-cThXw6ea?dl=0


Is this even safe?  My careful measurements shows only  a few thousands of material between the flash channel  and the exterior of the threads.  I did not do this, BTW.  It came like that.  The bit is a #32.  The hole is  1/8".   

These plugs are un-obtanioum right now.  Would it be helpful to silver solder a 1/8" plug in the hole and do it properly?

[EC121]

Dropbox doesn't let me in.

[Scota4570]

Sorry, try again.

[EC121]

I once had a Hawken I was test firing for a friend blow out right in the corner between the bolster and the breech.  It must have been paper thin right in the angle.  To get the hole centered in the breech they have to drill to the nipple seat very near the corner.  Wouldn't have to miss much to make it too thin.  I imagine there are more like yours than we realize.  My friend drilled and tapped the hole. Then he installed a screw and redrilled it.     

[Scota4570]

I added an illustration to the dropbox link to explain my concern better.

https://www.dropbox.com/sh/8qsi2tqrf4fqgv6/AAB5oigMHp9FhweY-cThXw6ea?dl=0&preview=plugs.bmp
https://www.dropbox.com/s/5ckgoeyejv2to66/plugs.bmp?dl=0

[ltdann]

Drop box chokes up my computer.  Can you upload directly to the forum? http://americanlongrifles.org/forum/index.php?topic=43575.0

[Scota4570]

free unlimited photo hosting

That was much easier than that dog-on site I was using.  Thanks!

So, I am not likley to find another plug.  The maker's shop is being moved.  It appears the vendor or middle man did the ill advised drilling.  I will not use this plug under any circumstance. 

Can it be repaired?  I was thinking of silver soldering, high temp real type, a piece of 1/8" mild seel rod to fill the hole.  I would coat the whole plug with water/Kasenite slury or borax flux to prevent scaling.  Multiple MAPP gas torches provide the heat.  The plug face would then be properly machined to the second example in my drawing. 

 

[ltdann]

Much better.  I don't believe I'd use that plug in it's current configuration either!  I believe  you and EC are onto the right solution/solutions.  I believe either way would be safer than it is now.

[ron w]

I don't believe i'd use that plug, nor would I use it with a silver brazed plug installed and re-drilled.

[D. Taylor Sapergia]

I cannot tell just by looking at an image if there is a danger here, or not.  I will tell you that I personally have built around two hundred rifles with that style of plug and have had only one failure.  The failure was a plug on an English Sporting rifle in which the owner insisted on using 777 and Pyrodex against my advice.  His cleaning regime failed to remove fouling from the plug and the consequence was a number of pin holes in the cavity, one of which perforated the junction you have indicated.  I replaced the plug in his barrel with an identical plug, proofed it thoroughly and reiterated my insistence on using black powder only in the rifle.

Why don't you install the plug, proof the barrel and breech, and see where it leads.

[FlintFan]

Agreed.  Without knowing exactly how much metal is between the hole and the corner it's impossible to determine if it is safe or not just from the pictures.  Have seen many plugs (and guns built from them) drilled like this and have never seen it become an issue. 

[bgf]

The theory is that minimizing the passage length and severity of angles provides quicker ignition.  In reality, the small drill necessitated by the layout makes it prone to plugging up fairly easily. One with larger passage and fat ignition chamber at right angles would be better, in my opinion, if you could obtain an undrilled casting, especially if you added a clean out screw.

Incidentally, a friend of mine went through several of these (from a bin) before picking the one with the most metal left.  Many are thin, apparently, but they don't seem to be failing left and right, either...

[ltdann]

  The failure was a plug on an English Sporting rifle in which the owner insisted on using 777 and Pyrodex against my advice.  His cleaning regime failed to remove fouling from the plug and the consequence was a number of pin holes in the cavity, one of which perforated the junction you have indicated.

Here in Kaliforniastan, they regulate GOEX like a big dog. There's only one distributer that I've found within a reasonable driving distance. I'm allowed 1 pound of BP....total, and I have to sign away my first born for that.  I pay $33 per pound and that makes the flinter a little more pricey to shoot.   Making my own would get me the chair, I'm sure

Naturally, I can have up to 25 lbs of the synthetic stuff.  What I've  been doing is using Goex in the pan and synthetic as the main charge, with good results.

Can you elaborate a little more on your comment?

[Scota4570]

Further research indicates this is an acceptable "industry standard" way to do it. 

I will proof it.  Any suggetions on a fair 54 cal  proof load? 

I will complete it and consign it.  I have been wanting to test those waters on doing that as a side business anyway.

I may do another in the future, but done my way and more from scratch.  That will be the "keeper" rifle.

[Daryl]

200gr. 2F (roughly double load) with one bare .535" ball on powder, one patched .535" ball over that one - for proof.

 

[Scota4570]

After researching this I found some things out that may be usefull to somebody. 

-Track makes these plug/tang sets.
-Track machines them in house from their castings
-Track will not sell you one that is threaded, but not angle drilled
-Track will sell you raw castings that  you can machine yourself