carbon fibre pen gun

[POLAND_SPUD]

lol alcohol Y U make me forget things?


since it worked well it seems I give good advices, don't I ? heh

[sharpshooter11000]

Haha

Looks really nice JSR, loving the carbon fibre! I'm guessing the metal parts are epoxied in and you didn't machine threads in the CF?
I wonder what the performance increase would be if you used .177 pellets... (With a .177 barrel, of course)

[POLAND_SPUD]

I wonder what the performance increase would be if you used .177 pellets

there won't be any performace increase to be honest

heavier ammo equalls more efficient system - that's due to the speed of sound

so .22 cal version is more efficient than .177 cal - at least as far as energy put in by muzzle energy achieved is concerned - it could be different if you focus on penetration, which jsr has found to be better for .177 cal than .22 (IIRC)

[jackssmirkingrevenge]

I'm guessing the metal parts are epoxied in and you didn't machine threads in the CF?

Yup, epoxy to epoxy, dust to dust

there won't be any performace increase to be honest

heavier ammo equalls more efficient system - that's due to the speed of sound

Yup, for a given system, bigger bore and heavier projectile will give more muzzle energy.

so .22 cal version is more efficient than .177 cal - at least as far as energy put in by muzzle energy achieved is concerned - it could be different if you focus on penetration, which jsr has found to be better for .177 cal than .22 (IIRC)

Time for one of my favourite quotes te be dug up

A 68 pounder smoothbore and a 7 inch Armstrong gun firing 200 lb shot had been fired at 4.5 inch plate backed by 18 inches of teak. The 68 pounders had penetrated the target, while the 200 pounder had made hardly any impression on it. Noble showed that the answer lay in the relative velocity of the two projectiles. The 68 pounder had been moving at 1,425 feet per second when it struck, while the 200 pounder was loafing along at a mere 780 feet per second. On the face of it, the 200 pounder with 156,000 foot-pounds of energy should have out performed the 68 pounder with 96,900, but the low velocity of the heavier projectile allowed the plate to deform and resist the blow, whereas the higher velocity of the 68 lb shot tore through the plate before it could begin to absorb the blow.

As Noble said in his paper, "What is wanted is velocity; if you sacrifice it to weight you will only be able to keep knocking at the door without entering."

[sagthegreat]

how many psi can this tubing handle?

[jackssmirkingrevenge]

how many psi can this tubing handle?

It's not pressure rated, but given the 1:10 ratio of wall thickness to inner diameter, and small bore, I'm happy to take it to "normal" 300-400 psi pengun pressures.

[Gun Freak]

You make me want to give up, Jack. Carbon Fiber makes everything look cooler, I guess

[sagthegreat]

What is the highest psi/ smallest wall thickness steel we can get, lets make some pen guns that look like pens and go to 1000 psi, and sell them to the military

[jackssmirkingrevenge]

You make me want to give up, Jack.

You misunderstood, I make you want to invest in machine tools

lets make some pen guns that look like pens and go to 1000 psi, and sell them to the military

The military have no use for pen guns, and if they did, they would probably use powder burning ones...

[jakethebeast]

How about upping pen gun with steroids and then put it to a cane? Shouldn't be too hard...

[jackssmirkingrevenge]

How about upping pen gun with steroids and then put it to a cane? Shouldn't be too hard...

A cane gun would definitely have much more power due to the bigger volume and barrel length.

http://www.ebay.com/itm/Derby-Handle-Ad ... 3cc7dc0c7c

Pretty cheap if one wanted to convert it...

[sagthegreat]

lets make some pen guns that look like pens and go to 1000 psi, and sell them to the military

The military have no use for pen guns, and if they did, they would probably use powder burning ones...[/quote]


Spys would have a use, and not to mention the types of substance that can be put on hollow tip pellets to make them "magical"

[jackssmirkingrevenge]

Spys would have a use, and not to mention the types of substance that can be put on hollow tip pellets to make them "magical"

If you have magical substances then you don't need much power if they do need power, powder burners offer it in a much more compact package:



A pneumatic pen gun with the equivalent power to a 22 rimfire would have to be pretty huge.

[sagthegreat]

I want that firing cap thing up have. But I don't have a lathe...

[jackssmirkingrevenge]

I want that firing cap thing up have. But I don't have a lathe...

You can make a request here I'm sure someone nice can make you something for a few bucks.