Author Topic: finally fired live loads out of my coehorn  (Read 819 times)

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Offline Rickk

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finally fired live loads out of my coehorn
« on: July 23, 2006, 03:44:05 PM »
I finally took my Coehorn out back and fired a few live rounds.

It is a 2.25 inch Hern Coehorn

Powder chardges were 1/2 ounce Cannon grade Goex.

I fired two 2# lead balls, and also a 5.25 inch long 2.125 diameter muffler pipe filled with concrete (about 1#)

I found both lead balls. They hit trees before stopping, and I found them at about 50-60 yards. I am thinking they would have landed at about 100 yards if the trees were not there.

The 1# concrete muffler pipe was not found. I heard it leave... then I heard nothing for a while... then I heard it splash down inthe trees... maybe 200-300 yards away would be my guess. My "range" is 500+ yards, but I could not see the impact, so I need to try to reduce the load for that projectile.

The vent hole is angled toward the breech (specifically to make small charges more possible), and enters the bore at .400 from the breech plug. The vent punch hits the breech about dead center when inserted into the vent hole.

When I fired the 2 pound balls, there was no issue puncturing the aluminum foil bag with a blunt (flat) vent punch.

When I fired the concrete pipe the blunt punch hit the pipe and would not enter the chamber. I have a pointy punch, which I found from firing blanks is more likely to cause a misfire. I tried it and was able to sneak it under the concrete pipe and fire the round. I think that with such small charges a couple of coorogated cardboard spacers may be needed to make sure I can get the vent punch to the powder.

I must admit, when I fired the 1# concrete filled muffler pipe the noise seemed way louder than when firing the 2# lead balls. I need to fire another one to get concurance on what happened.

For what it was worth, the muffler pipe was cut with a tubing cutter. The cutter tapered in the ends of the pipe. This no doubt made it easier for the concrete to stay put. From what I saw of the projectile leaving the bore there is little doubt that the concrete stayed in the pipe. I do wish I could have found it to look at it.

I painted all three projectiles flouresent blue to help find them, but only found the two lead balls.

The lead balls, while they hit trees, probably could be reloaded again with no issues.

This was all with 1/2 ounch charges of Cannon powder. From what I have been able to deduce the literature, 1.5 ounces of Cannon is probably a max load for 2-3 inch bore.

These things will really fly :-)

Offline Cat Whisperer

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Re: finally fired live loads out of my coehorn
« Reply #1 on: July 23, 2006, 03:53:08 PM »
Rickk -

These are events that you'll remember forever!

You might well find the projo just under the surface of the ground.  I frequently put the 7-1/2 lb 4" cement filled projo's underground.

Tim K                 www.GBOCANNONS.COM
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U.S.Army Retired
N 37.05224  W 80.78133 (front door +/- 15 feet)

Offline Rickk

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Re: finally fired live loads out of my coehorn
« Reply #2 on: July 23, 2006, 04:00:31 PM »
From what I saw of the lead balls, I am thinking that if they hit trees just prior to impact, they will be found landing on the surface. I'm not sure what would happen if they simply touched down.

Both lead balls were "just laying there". I saw a pine tree with some stuff missing from it at about 60 feet above the first balll.

The concrete pipe was heard hitting trees just before impact, but it was quite a ways away. I couldn't find it, and my 4 year old (who can see way better than I can) couldn't find it, but it was so far away that it was hard to be sure we were on the correct course when we looked for it.

I guess I need to cut some more firewood on my range to give me a better field of view.

Offline Michael Az

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Re: finally fired live loads out of my coehorn
« Reply #3 on: July 23, 2006, 04:30:39 PM »
Sounds like fun. Don't forget to show us some photos!
Michael

Offline Rickk

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Re: finally fired live loads out of my coehorn
« Reply #4 on: July 23, 2006, 04:32:24 PM »
Two things I did note though...

The 2# lead balls were still noticably hot when i found them several minutes after fireing them. I was surprised that something so big, in contact with the fire for so little time, were still so hot.

The lighter projectile, with the dinly load, was really, really load. I did grease the pipe with grease before loading. I wonder if the grease ingited and became part of the explosion?

Offline Double D

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Re: finally fired live loads out of my coehorn
« Reply #5 on: July 23, 2006, 05:46:26 PM »
I finally took my Coehorn out back and fired a few live rounds.

It is a 2.25 inch Hern Coehorn

...I fired two 2# lead balls, and also a 5.25 inch long 2.125 diameter muffler pipe filled with concrete (about 1#)...

When the discussion first started about using muffler pipe someone mentioned to me, I believe off line, about the potential hazard.  They are right.  There is a very real danger of a spark from metal on metal contact.  It was pointed out that both N-SSA and AAA prohibit the use of steel projectiles for just this reason. It is unsafe.


Quote
The vent hole is angled toward the breech (specifically to make small charges more possible), and enters the bore at .400 from the breech plug. The vent punch hits the breech about dead center when inserted into the vent hole.

When I fired the 2 pound balls, there was no issue puncturing the aluminum foil bag with a blunt (flat) vent punch.

When I fired the concrete pipe the blunt punch hit the pipe and would not enter the chamber. I have a pointy punch, which I found from firing blanks is more likely to cause a misfire. I tried it and was able to sneak it under the concrete pipe and fire the round. I think that with such small charges a couple of coorogated cardboard spacers may be needed to make sure I can get the vent punch to the powder...

...Those thiings will really fly :-)


Why would the punch hit the pipe?  Does this gun have a chamber? I am thinking this is a straight bore and not a chambered bore.

Stick with the lead balls or better yet to cut down on the stress on your gun look into getting set up with zinc.  The balls will be lighter and will deform less.  They will also go further with the same charge than the lead. They will also reduce pressure and recoil load on the gun.

You did good starting with a reduced load. Smart thing to do.  Now you need to go up in increments to get your range. Sounds like you are having fun. I am envious!

Offline Rickk

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Re: finally fired live loads out of my coehorn
« Reply #6 on: July 24, 2006, 12:07:16 AM »
the bore is straight... no chamber.

The pipe is tapered on both ends (from the tubing cutter), and there is several layers of masking tape wrapped wound the pipe near each end to reduce windage and also to prevent metal to metal contact. I applied grease to the outside as well. My fear was not of a spark, but of barrel scratching.

Offline Cat Whisperer

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Re: finally fired live loads out of my coehorn
« Reply #7 on: July 24, 2006, 12:13:39 AM »
the bore is straight... no chamber.

The pipe is tapered on both ends (from the tubing cutter), and there is several layers of masking tape wrapped wound the pipe near each end to reduce windage and also to prevent metal to metal contact. I applied grease to the outside as well. My fear was not of a spark, but of barrel scratching.

The tape reducing the windage is the cause of the louder noise (higher pressure).  I had to use it when my first mortar (1974) in beer can caliber gained windage - because the cans in 1975 moved the rim from the outside to smaller than the outside diameter - creating too much windage.  Soup cans still have the outside sized rim and work well.

Tim K                 www.GBOCANNONS.COM
Cat Whisperer
Chief of Smoke, Pulaski Coehorn Works & Winery
U.S.Army Retired
N 37.05224  W 80.78133 (front door +/- 15 feet)

Offline rusty barrels

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Re: finally fired live loads out of my coehorn
« Reply #8 on: July 24, 2006, 03:23:57 AM »
Only 300 grs launched the balls that far, I wonder how far they would have gone with a full once. I thought that drilling the vent hole at an angle to the chamber was not recomended (least on long barreled guns). I think I would have been shock too finding the balls were still hot, I wonder what generated so much heat. I'm jealous cause I'm still along way from firing my first shot.