"steamer" wrote in message
...
--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

As a crude guess, I would suggest a 1" piece of plate steel. That should
stop anything a 20mm cannon can dish out save for maybe a hardened ball. To
be on the safe side, I would gradually work up to full load (and ball
harness) by shooting with reduced charges and projectiles of softer texture.
Be esp. aware of the bounceback tendency of hard projectiles.

Bob Swinney

PS: If you get disgusted with the project, sent me the workpiece and I'll
take it from there!


"steamer" wrote in message
...
--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

Um.. Ed... My 1/2" cannon, with newspaper projectile, has the police band
busy with a "mysterious report" of some sort. I was, um, wondering, how you
expect a 20mm cannon to be anything but, well, um, ..noticable?

Have fun

"steamer" wrote in message
...
--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

On Thu, 11 Sep 2003 16:01:09 GMT, steamer wrote:

--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

At least 3 feet of well packed dirt., or a nice 9/16" Hot rolled steel
plate at a 45' angle.

While its only a small black powder arm..it will still shoot through
both sides of a 4x4 piece of lumber..so be careful.

Gunner

--
The problem with defending the purity of the English language is that
English is about as pure as a cribhouse whore. We don't just borrow words;
on occasion, English has pursued other languages down alleyways to beat
them unconscious and rifle their pockets for new vocabulary.
--James D. Nicoll

--This time of year when the propane guns are banging away to
scare the birds away from the grape crops who's to know? Heh.

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

How about John Kerry?
JR
Dweller in the cellar

steamer wrote:

--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
Doubt yourself, and the real world will eat you alive
The world doesn't revolve around you, it revolves around me
No skeletons in the closet; just decomposing corpses
--------------------------------------------------------------
Dependence is Vulnerability:
--------------------------------------------------------------
"Open the Pod Bay Doors please, Hal"
"I'm sorry, Dave, I'm afraid I can't do that.."

On Thu, 11 Sep 2003 20:15:29 -0700, JR North
wrote:

How about John Kerry?
JR
With Cruz Bustamonte and Diane Swinestine as spares.

Gunner

Dweller in the cellar

steamer wrote:

--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

--
The problem with defending the purity of the English language is that
English is about as pure as a cribhouse whore. We don't just borrow words;
on occasion, English has pursued other languages down alleyways to beat
them unconscious and rifle their pockets for new vocabulary.
--James D. Nicoll

Hey Steamer,

To stop from scaring the neighbours, a big silencer would be best!!

A guy I bought a mill from made cannons that fired something slightly
smaller, 3/4" ball bearings. He had a 3/4" plywood box with one open
end, that was permanently closed on 4 sides and had a hinged lid on
the fifth. Recollection has it that it was about 24" square in
section, by the 48" long that a sheet of ply would provide. The box
had a pair of rails full length just below the lid part, that allowed
him to hang newspapers inside the box on sticks, sort of like you see
newspapers in the public reading room of libraries. He would "fill"
the box with the papers by just hanging the sticks of newspapers in it
so I recall that they were not jammed "tight" in there. Then push the
box up against the footing of the wall of the garage, set up the gun
about 3 feet from it in the garage, fire into the open end, then open
the lid and lift the papers out one "stick" at a time to check for
the ball. The last paper with a hole indicated how well it did.

There's a bit more story to this.....I won't tell you how, or what
happened when, he inadvertently rammed up a triple charge, but he
never did find the ball.

Take care.

Brian Lawson,
Bothwell, Ontario.
XXXXXXXXXXXXXXXXXXXXXXXXXXXXX

On Thu, 11 Sep 2003 16:01:09 GMT, steamer wrote:

--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

Brian sez:

"Outdoor rifle/target ranges just use an embankment of sand."

I enjoyed your story about the newspaper bullet trap - just goes to show
enough of enything will stop anything. BTW, embankments on shooting ranges
are more generally made of available earth, rather than of sand. Of course
the ones on the beach ...

Bob Swinney

"Brian Lawson" wrote in message
...
Hey Jim,

Should work OK. I saw a 150MM recoilless rifle pretty much reposition
a 12 foot mound of dirt, so this gun shouldn't have a problem.

Take care.

Brian Lawson,
Bothwell, Ontario.
XXXXXXXXXXXXXXXXXXXXX
On Thu, 11 Sep 2003 09:20:32 -0700, Jim Stewart
wrote:

steamer wrote:

--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading
mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

A mound of earth?

steamer scribed in
:

--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle
loading mind you, but what would it take to stop something coming
out of that barrel so's I don't scare the bajeezus out of the
neighbors?

don't fire anything heavier than a pill bottle and you have no
worries (-:

but seriously....something large and light for it's size will stop
pretty quickly by itself, like a shotgun shot cup (I've found them on
the local .22 only range), even more so if it is not aerodynamic in
any way.

any kind of solid ball will take a fair bit of stopping I'd say. at
least 3/4" plate at 45 degrees to deflect it into sand. might take
more. but can you be sure of hitting it?

--
swarf, steam and wind

--
David Forsyth -:- the email address is real /"\
http://terrapin.ru.ac.za/~iwdf/welcome.html \ /
ASCII Ribbon campaign against HTML E-Mail - - - - - - - X
If you receive email saying "Send this to everyone you know," / \
PLEASE pretend you don't know me.

John Hofstad-Parkhill scribed in
:

Um.. Ed... My 1/2" cannon, with newspaper projectile, has the
police band busy with a "mysterious report" of some sort. I was,
um, wondering, how you expect a 20mm cannon to be anything but,
well, um, ..noticable?

roflmao.... if we hear mysterious reports around here, it IS the
police.... we used to live a block from the police barracks and every
Christmas and New Year they'd make lots of noise. mostly 12 gauge
shotgun, and some 9mm. seems they shied away from the 5.56
NATO rifle stuff.

swarf, steam and wind

--
David Forsyth -:- the email address is real /"\
http://terrapin.ru.ac.za/~iwdf/welcome.html \ /
ASCII Ribbon campaign against HTML E-Mail - - - - - - - X
If you receive email saying "Send this to everyone you know," / \
PLEASE pretend you don't know me.

Our military uses Russion made T-54's and T-72's for plinking targets with
thier 20mm guns. They should know.
Tom
"steamer" wrote in message
...
--I'm trying to figure out what might serve as an effective
backstop for my 20mm cannon. Strictly black powder and muzzle loading mind
you, but what would it take to stop something coming out of that barrel
so's I don't scare the bajeezus out of the neighbors?

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

Bob Swinney wrote:
Brian sez:

"Outdoor rifle/target ranges just use an embankment of sand."

I enjoyed your story about the newspaper bullet trap - just goes to show
enough of enything will stop anything. BTW, embankments on shooting ranges
are more generally made of available earth, rather than of sand. Of course
the ones on the beach ...

IIRC, in Desert Storm (is that hyphenated?) a APFSDS round went through
10 meters of sand to make a kill on an enemy tank.

However, these go faster than most black powder weapons.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
To do is to be
To be is to do
Do be do be do do

On Fri, 12 Sep 2003 08:12:39 -0400, Brian Lawson wrote:

|Hey Steamer,
|
|To stop from scaring the neighbours, a big silencer would be best!!
|
|A guy I bought a mill from made cannons that fired something slightly
|smaller, 3/4" ball bearings. He had a 3/4" plywood box with one open
|end, that was permanently closed on 4 sides and had a hinged lid on
|the fifth. Recollection has it that it was about 24" square in
|section, by the 48" long that a sheet of ply would provide. The box
|had a pair of rails full length just below the lid part, that allowed
|him to hang newspapers inside the box on sticks, sort of like you see
|newspapers in the public reading room of libraries. He would "fill"
|the box with the papers by just hanging the sticks of newspapers in it
|so I recall that they were not jammed "tight" in there. Then push the
|box up against the footing of the wall of the garage, set up the gun
|about 3 feet from it in the garage, fire into the open end, then open
|the lid and lift the papers out one "stick" at a time to check for
|the ball. The last paper with a hole indicated how well it did.

So for a 2" ball, make it 4-ft on a side, and substitute carpet scraps?
Rex in Fort Worth