Really easy and Really cool breech loading

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DinerKid
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Sat Jun 20, 2009 3:24 pm

i was thinking of using one of these valves and putting a female adapter tho the outer edge of it (if i have to smooth it out or sand it down that is fine i would probably toss it on a lathe and do it that way) then fitting the barrel t it so that the barrel and front face of the valve are touching neither is sleeved into the other instead the valve and the barrel are sleeved into a larger coupler. what do you think? i figured this would be way easier to do in a one stop trip to Home Depot rater than trying to find an odd valve with a small ball bore and larger valve bore.

here is a picture for reference it is nothin fancy just a pic of a normal ball valve.
http://www.tradevv.com/TradevvImage/pro ... A43ee4.jpg
CaryChleborad
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Sun Jun 21, 2009 11:15 pm

suburban spudgunner wrote:That's an interesting concept. Just one more reason why I wish I had access to a machine shop...
I offer machine shop service....

Email Cary@Factenginerring.com
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Technician1002
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Sun Jul 12, 2009 10:33 pm

THUNDERLORD wrote:
In a machine shop I worked at a guy was slapping chips from a piece in a milling machine with gloved hand...Bit caught his glove, twisted his arm around, breaking a bunch of bones from his hand, wrist and arm... :shock:
A little common sense goes a long way. Where I work, gloves are forbidden near the power saws and drill press for that very reason. dig dig hunt.. AaaaHa;
Use appropriate safety equipment, such as goggles, earplugs and dust masks. Do not wear gloves when working with most tools. Always wear eye protection when working with metal. Do not wear sandals, open-toed or canvas shoes when working with tools. Avoid loose-fitting clothes that might become entangled in a power tool. Remove rings and other jewelry.
Located here.. http://www.nasdonline.org/docs/d000901- ... 00903.html

When using a drill press, the belt tension is adjustable. Use a slower speed, reduce the belt tension and go slow. Test belt tension by stalling the chuck by hand. Too much torque can cause injury and bent, broken tools and parts. The spring tensioner and tension lock can be used to limit torque.

Be safe guys. Learn your tool safety and abilities.
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inonickname
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Sun Jul 12, 2009 10:46 pm

You should never really put your hands near a milling machine no matter what. Many have huge spindle speeds (8000+) and up to 15 horsepower, so you'll always come off second best. The bits rip through flesh extremely quickly.

Totally agree with the glove thing, they should really only be worn when carrying out activities such as welding.

Not only do gloves create large flappy bits of material for tools to grab onto, they lower your dexterity massively. For example, I don't wear gloves while mixing flash. If something goes wrong I will at least end up with horrible burns and have parts of my fingers blasted away whether I wear gloves or not, but I'm twice as likely to have an accident wearing gloves. I don't really use flash anymore anyway.
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boyntonstu
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Mon Jul 13, 2009 7:01 am

covey12 wrote:hey guys i found this up on youtube, i didn't make it, its twoleafs idea

[youtube][/youtube]

In some barrel over chamber designs, you could load a patched ball through the ball valve, ram it past a T, and close it.

Replace the cap with a valve.

IOW The ball valve is the breech.

http://i348.photobucket.com/albums/q339 ... /crude.jpg

Image

BoyntonStu.
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Hotwired
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Mon Jul 13, 2009 7:13 am

Good wheeze there BoyntonStu.

One undesirable feature of having to dismantle the breech to reload is exactly that.

Although to be perfectly honest, if you are firing arrows longer than your barrel I don't think you'll save anything much by being able to breech load :P
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boyntonstu
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Mon Jul 13, 2009 8:24 am

Hotwired wrote:Good wheeze there BoyntonStu.

One undesirable feature of having to dismantle the breech to reload is exactly that.

Although to be perfectly honest, if you are firing arrows longer than your barrel I don't think you'll save anything much by being able to breech load :P
The photo was not of my gun.

I used it as an example of how to make a really easy breech loader for cylindrical or spherical patched projectiles.

AAMOF Theairgunman, the builder of this gun, and owner of airgununiverse.com , does not usually shoot darts or arrows.


See: http://www.airgununiverse.net/beginner2.html


Breech loading patches reverses the usual muzzle loading situation and I wonder how well the front patch position would work?

Another point is the dead space behind the projectile to the valve. I can think of a few ways to minimize it. However I wonder how much loss of efficiency this volume would cause?

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Hotwired
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Mon Jul 13, 2009 9:19 am

When you consider the volume of that particular chamber, not a lot.

I didn't think it was your cannon but I used the word "you" in place of "someone" ^^

Only one way to be sure about the patches :)

I'm not too keen on the idea of using them.

Besides, patches were and are used to secure the bullet

(1) against the powder and
(2) in the barrel then
(3) to act as wadding for an undersized bullet on firing

When thinking about it for an air gun

(1) There's no powder or in fact anything for it to stop against when breech loading
(2) Still valid
(3) Still valid

So loading from either end with a patch will mean a ramrod but breechloading means you're pushing the patched bullet out into the tube with just the patch to support it. If the patch doesn't secure it from moving both ways it could either come out the muzzle or do something annoying at the valve end.

While if you muzzle load you can have a lip or similar to ram the patched bullet up against for extra security and don't have to push it past the large valve port along the way.
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boyntonstu
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Mon Jul 13, 2009 9:37 am

So loading from either end with a patch will mean a ramrod but breechloading means you're pushing the patched bullet out into the tube with just the patch to support it. If the patch doesn't secure it from moving both ways it could either come out the muzzle or do something annoying at the valve end.

If the bullet is pushed beyond the T, I do not believe that it would be sucked back to the valve.

While if you muzzle load you can have a lip or similar to ram the patched bullet up against for extra security and don't have to push it past the large valve port along the way.


The valve could be a larger diameter than the barrel and allow for plenty of clearance. For example a 3/4" valve on a 1/2" barrel.

A lip or similar could be made inside the barrel.


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Hotwired
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Mon Jul 13, 2009 10:16 am

boyntonstu wrote:If the bullet is pushed beyond the T, I do not believe that it would be sucked back to the valve.
No, no I don't mean being sucked back, I mean if the patch fails to secure it, it could either roll out the muzzle or roll back towards the valve and what it does there is anyones guess. While on a muzzle loader it is being rammed against the powder which packs the wadding in tighter and there is only the option of falling out of the muzzle left. It can't go any further into the powder.

You can work around using patched projectiles from the breech but you do get more problems than if you stuffed the same projectile in from the muzzle. And you'll still be using a ramrod albeit a shorter one.
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boyntonstu
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Mon Jul 13, 2009 11:21 am

Hotwired wrote:
boyntonstu wrote:If the bullet is pushed beyond the T, I do not believe that it would be sucked back to the valve.
No, no I don't mean being sucked back, I mean if the patch fails to secure it, it could either roll out the muzzle or roll back towards the valve and what it does there is anyones guess. While on a muzzle loader it is being rammed against the powder which packs the wadding in tighter and there is only the option of falling out of the muzzle left. It can't go any further into the powder.

You can work around using patched projectiles from the breech but you do get more problems than if you stuffed the same projectile in from the muzzle. And you'll still be using a ramrod albeit a shorter one.
I have heard differing opinions about having a rear patch.

A 3"-4" ramrod is all that would be necessary.

If you inserted a piston with a narrow rod extension behind the projectile it could not roll back and it would reduce the dead space to almost zero.

(A little 'loop' for retrieving the piston back out through the valve would be nice.)

If a projectile rolled back to the valve (or anywhere aft the vertical part of the T), there would be a clear path between the chamber and the muzzle for the air to harmless escape.

BoyntonStu
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