Fullstock Hawken In .58!

[Mulebrain]

Now I understand why the percussion lock has never been fired!( Note rust in pictures) There is NO way those lock bolts are going to withstand the backpressure against that drum. :nono: I believe you will be breaking the wood around the lock mortise, and endangering your forehand if you fire the gun that way.

Please don't risk injuring yourself or others with this percussion design. Shoot the gun as a flinter, instead. :shocked2: :thumbsup:

I have documentation of the percussion lock being used, and the load data. I am surprised that a master gunsmith and a gun builder with over 40 years building guns would create a harmful gun!

What gives?

 

[LaBonte]

Perhaps the drum is vented? If so no more problems with back pressure than with a flinter.......

 

[Leonredbeard]

LaBonte,
Yours was the answer I expected. Yes the blast comes out of the vent and dissipates. But the bolster gives it a potential projectile in front of the pressure. That is what I am concerned about.

Mule Brain,
If you do fire it in percusion please do give us a full report. (No pun intended) It does seem like it would leak a lot of gas between the drum and barrel. But then so did the hall and so did the Ferguson and all other breechloading flinters.
volatpluvia

 

[mark starr]

That rifle look like a gun a freind had years ago was the builder from fort collins colorado by any chance? anyhow nice rifle ... looks like an elk killer to me

 

[Fullstock58]

The top pic is my Hawken flint in 58cal:

The 3rd rifle down was built in Fort Collins, or Loveland CO by a Mr Ray Ezinga (sp.

 

[Dphar]

Now I understand why the percussion lock has never been fired!( Note rust in pictures) There is NO way those lock bolts are going to withstand the backpressure against that drum. :nono: I believe you will be breaking the wood around the lock mortise, and endangering your forehand if you fire the gun that way.

Please don't risk injuring yourself or others with this percussion design. Shoot the gun as a flinter, instead. :shocked2: :thumbsup:

I concur completely.
It is beyond my comprehension that someone would make something of this sort.

Given the level of ignorance displayed in the "percussion conversion" I would want to debreech and inspect before I shot it as a flintlock.
assuming the lock does not blow off (it will vent pressure as the lock springs away under pressure) its going to leak gas in all directions.
This ranks right up there with the stupidest thing I have seen in 40+ years as a ML shooter and gun maker.

Dan

 

[Dphar]

That drum system should work fine. We were using an item similar to that 30 years ago, only it was really ugly. It was a block of brass with a nipple in it that replaced the frizzen. It had a hole drilled to line up with the vent. A corresponding flat piece of brass was put in the jaws to hit the cap.
From what I see, this drum system not only looks much better but will work better also.

The frizzen type conversion is a different situation *if* done as done historically. Its still flaky, just not as flaky.
You have to remember one thing in all this. If parts come adrift they will pass down the firing line. It some one takes a drum or other part in the side of the head the consequences are unacceptable.
I have had a modern drum come adrift, broke off acutally, back in the 60s. I would not want to be to the right side of this. As it is I don't stand on the lock side of drum and nipple guns when they are being fired anyway. I learned the first time.
Things of this sort are just accidents waiting to happen.

Dan

 

[paulvallandigham]

I was thinking, with horror, at the kind of flame and gas debris that comes out of a barrel/cylinder gap in any revolver. How would you deal with those gases blowing down between the barrel and the "drum" into the lock mortise????? And, of course, some of that gas is going to coming back at the shooter?!!! :shocked2: :haha: :rotf:

I am not criticizing the current owner of the gun, nor even the original builder. Crazier stuff has been tried. I just don't want to be around when the owner tries to shoot that Percussion " Conversion".

( I was reminded of a Russian Nagant Revolver, in about 30-32 caliber, that has a cylinder that moves forward as the hammer is cocked to seal each chamber to the barrel before the hammer falls and fires the gun. Some of those guns came into this country a few years back, and a friend took one out and shot it, and it worked! I just don't see a similar arrangement with this "conversion". This "Rube Goldberg" reminds me of trying to stop the water coming out of the garden hose by putting my thumb on the nozzle. It didn't work when I was a little kid, and as strong as I have become as an adult, I still doesn't work!) )

 

[Tom Compton]

Re percussion conversion. Appears it is designed to work with the touch hole liner in place. Would this minimize pressure against the drum?

 

[Mulebrain]

Re percussion conversion. Appears it is designed to work with the touch hole liner in place. Would this minimize pressure against the drum?

That is correct!

The vent liner is recessed some, to receive the protrusion on the drum. It is held by force in place by the two lock screws.

This gun has been fired with the caplock installed with 90 grains of ff goex.

If there is enough pressure coming out of the vent liner to turn that drum into a missile :hmm:

I am surprised a master gun builder would build a death trap :hmm:

 

[varsity07840]

Re percussion conversion. Appears it is designed to work with the touch hole liner in place. Would this minimize pressure against the drum?

That is correct!

The vent liner is recessed some, to receive the protrusion on the drum. It is held by force in place by the two lock screws.

This gun has been fired with the caplock installed with 90 grains of ff goex.

If there is enough pressure coming out of the vent liner to turn that drum into a missile :hmm:

I am surprised a master gun builder would build a death trap :hmm:

George Dech was indeed a well known and respected
gun builder, especially in this area(eastern PA/NJ). I think that perhaps the percussion set up was an after thought by someone other than George. It looks like a short cut to avoid having to thread the drum into the breech and drill and index the nipple to line up with the hammer. Is there an actual liner threaded into the breech or is there just a countersunk recess? I can't tell from the picture. Either way, that touch hole seems to be pretty big. It also looks like the touch hole itself projects slightly foward of the bottom of the recess. The inside of the percussion lock certainly shows the corrosive results of shooting it that way. How well does the percussion plate fit in the flint mortise? Assuming both locks are L&Rs, their pecussion plate tends to be smaller, at least according to TOW.

Duane

 

[sniper68]

I checked this out when you first posted. :shocked2: I can not believe that such a competent builder would do something like that. Well done, beautiful rifle..... I would have the touch hole liner replaced as it looks over sized and who knows what else. I think this modification was done after the fact.
If you want the rifle convertible, make, or have made a "separate" drop in barrel assembly with a drum that you "don't" remove. It ain't that hard and works like a charm. The problem is, that you'll probably never use the percussion set up. I've done three of them. It's really not that hard and works as advertised.
The percussion setup you have there "CAN NOT" be safe. NO WAY!!!! :nono:
Don't look none to precession to me......

 

[Mulebrain]

Here is some more detailed pics, and install of the caplock. This gun was a custom build, and from the documentation I have the gun was ordered built this way! Now that documentation could be wrong as well! If it is not safe, then it will be made safe by installing a proper vent liner!

 

[sniper68]

If it is not safe, then it will be made safe by installing a proper vent liner!

 

[Zonie]

Thoughts on the Percussion conversion and barrel vent:

First off, the vent does seem to be very large but when used in the Flintlock setup it isn't unsafe.
It isn't really any larger than some of the somewhat worn original large caliber guns.

Yes, the vent will reduce the pressure of the gas that is blowing out of the vent hole when the gun is fired.

Will it reduce it enough to be safe to use the Percussion setup? Maybe but there will still be a lot of pressure at the joint trying to blow the lock off of the gun.

This is just ball parking but lets say the gun was fired with a 90 grain powder load under a .570 diameter ball. Depending on the powder, Lymans Black Powder Handbook says they saw breech pressures of around 6,000 PSI.
Lets say the smaller vent hole reduces the escaped pressure to 3,500 PSI.
The diameter of the drum in the reduced area where it is turned to a smaller diameter looks to be around 5/16 but there is going to be leakage around it so lets say the effective surface area that is subjected to the gas pressure is about 1/2 inch. That would give it an effective area of .1963 square inches.
That value multiplied by 3500 PSI equals 687 Pounds of force that is trying to blow the lock off of the gun.

While two lock screws should be able to resist this amount, it isn't like the force was acting directly on the screws in the direction of their bodies.
Because the screws are lower than the vent/drum there will be a twisting action imposed on them which they were not designed to withstand.

The bottom line in my opinion is the Percussion lock is an interesting feature and having it does enhance the value of the gun but I would not use it to shoot the gun on a regular basis.

The question of installing a new vent liner was made asking if it would fix the problem with the Percussion lock.
My answer is NO.
The only way to fix the Percussion system would be to remove the existing drum from the lock.
Drill and thread the barrel for a 3/8 diameter thread and install a new drum that screws directly into the barrel. The body of this drum would have to be adjusted so that the bolster of the lockplate supports it just like the commonly used system for most side drum Percussion rifles.

This large 3/8 diameter threaded hole would use a matching 3/8 diameter vent liner for Flintlock use.

 

[varsity07840]

Thoughts on the Percussion conversion and barrel vent:

First off, the vent does seem to be very large but when used in the Flintlock setup it isn't unsafe.
It isn't really any larger than some of the somewhat worn original large caliber guns.

Yes, the vent will reduce the pressure of the gas that is blowing out of the vent hole when the gun is fired.

Will it reduce it enough to be safe to use the Percussion setup? Maybe but there will still be a lot of pressure at the joint trying to blow the lock off of the gun.

This is just ball parking but lets say the gun was fired with a 90 grain powder load under a .570 diameter ball. Depending on the powder, Lymans Black Powder Handbook says they saw breech pressures of around 6,000 PSI.
Lets say the smaller vent hole reduces the escaped pressure to 3,500 PSI.
The diameter of the drum in the reduced area where it is turned to a smaller diameter looks to be around 5/16 but there is going to be leakage around it so lets say the effective surface area that is subjected to the gas pressure is about 1/2 inch. That would give it an effective area of .1963 square inches.
That value multiplied by 3500 PSI equals 687 Pounds of force that is trying to blow the lock off of the gun.

While two lock screws should be able to resist this amount, it isn't like the force was acting directly on the screws in the direction of their bodies.
Because the screws are lower than the vent/drum there will be a twisting action imposed on them which they were not designed to withstand.

The bottom line in my opinion is the Percussion lock is an interesting feature and having it does enhance the value of the gun but I would not use it to shoot the gun on a regular basis.

The question of installing a new vent liner was made asking if it would fix the problem with the Percussion lock.
My answer is NO.
The only way to fix the Percussion system would be to remove the existing drum from the lock.
Drill and thread the barrel for a 3/8 diameter thread and install a new drum that screws directly into the barrel. The body of this drum would have to be adjusted so that the bolster of the lockplate supports it just like the commonly used system for most side drum Percussion rifles.

This large 3/8 diameter threaded hole would use a matching 3/8 diameter vent liner for Flintlock use.

Ditto.

Duane

 

[Bob J]

That's a beauty there Mule Brain! It looks "business-like", yet attractive. Congrats!

I agree...a fine lookin' hunting rifle with plenty of "whompability"! A fullstock Hawken -type rifle looks right in flint :thumbsup: :thumbsup: