Lathe turned pellets

[john bunsenburner]

Well i guess all the CNC turned rounds made me jealos. I was bored, had lots of spare copper stock(8mm) and decided to make a few pellets for my not existing gun. My questions are:
Which of the two do you like better?
Which one has the better areodynamic capabilities?
How could i make the "perfect" pellet?
How do i make molds for these?

[Dave_424]

Prorably the smaller one. The longer one creates more drag due to the amount to rings it has. Just drill out the back end of the smaller one (Maybe a 6mm drill bit about 60% of the way through. This will make it more stable in flight due to it being front heavy.

About making moulds, You could either try and replicate the design in steel and try and make a milling bit in that shape (Gunna involve hardening and other things.) Then clamp a piece of aluminium in the tool post (Or some clamp to hold the material). And run the bullet shape into the material. Create another mould side, make some aligning posts and holes, a sprue and your finished.

This way might not even work but is the way i would firstly try it.

Dave

[jackssmirkingrevenge]

simpler and more effective.

[john bunsenburner]

Well if that is so effective why don't commercail pellets all use something liek that and have groves?

[Dave_424]

The reason for that is because that the guns have rifling, with that the forwards centre of gravity isn't as important becuase they are spin stabalized. Jack's drawing is best suited for smooth bore barrels

Dave

[psycix]

I'd stabilize them using fins, not using a hollow back (lots of length without much weight and kinda much drag due to the square back)
Though for fins, a lathe is not enough.

An idea that I once had is to build a projectile made from two smoothed cones (a bit raindroppish) which screw together, one steel, and one aluminum. The lighter aluminum part would act as a tail.

[jeepkahn]

I'd stabilize them using fins, not using a hollow back (lots of length without much weight and kinda much drag due to the square back)
Though for fins, a lathe is not enough.

An idea that I once had is to build a projectile made from two smoothed cones (a bit raindroppish) which screw together, one steel, and one aluminum. The lighter aluminum part would act as a tail.

Actually, fins are quite easy for a competent lathe/mill operator, think of it more like 4 deep flutes and you'll get the idea...

someone awhile back posted some flechette pics that illustrate what I'm refering to...

found it on wiki...

they wouldn't have to be this long, but you can get a good idea of the method of manufacture...

[john bunsenburner]

Those would need to be saboted, i want ammo that has the following attributes:
1.Can be used as is and can be quickly reloaded, no sabots ect.
2.Is extremly cheep to make and is quickly mad ein large numbers, having free acsess to lead i want to be able to shoot 500shots without feeling bad about wasting ammo!
3.A mold can easily be made for in out of alli
4.All parts can be lathe turned or made from hand tools, preferably little drilling and NO MILLING.
5. The amo can be used in a smooth bore(high pressure) and will still be accurate.

Now one question. How hard would it be to make a button rifling tool for aluminium barrels on a lathe and to then use thelathe to slllllllllllloooooowwwwwwwwlllllllly(slowly) turn the work piece and pull the button through(also slowly using some kind of aparatus)?

[Dave_424]

If you make the button rifling tool with relativley long cutters that are cut for the right twist rate you want like this. http://www.pyramydair.com/blog/images/r ... on-web.jpg

Then when you push it down the barrel, it will turn itself

EDIT: There was a website that I visited where a person rifled a .50 caliber STEEL barrel with a reamer. It worked wekk and produced some good groups. It was for a bigbore airgun

Dave

[jeepkahn]

What calibre are you wanting them to fit, are you wanting high fps, high ME, long range, high penetration small exit, lo penetration large exit.... with lead you have many options on projectile design to go after the differant attributes... if you want cheap, mass producability, make you some pellet molds...

[john bunsenburner]

Thanks, well jeep i would like range, penetration and lots of energy, i am planning of setting targets up at the end of the woads and shooting them form my house, which means i want to be shooting 500-700meters and acctually hit some targets.

[Dave_424]

I think that you will definatley need to have some BIG targets to be able to hit them.

What caliber will you be using?

I think a reamer like this http://www.gollino.com/carlos/ebay/shel ... -2back.jpg
Will rifle a barrel VERY niceley, should rotate as it cuts aswel.

Dave

[john bunsenburner]

.22 is the caliber i will be using the most(5mm in metric) if i find a supplyer of 4.5mm tubes i would consider that too. as targets ill be using medium sized archery targets(30x30cm).

[dewey-1]

Thanks, well jeep i would like range, penetration and lots of energy, i am planning of setting targets up at the end of the woads and shooting them form my house, which means i want to be shooting 500-700meters and acctually hit some targets.

I believe you are being a little to optimistic on getting the range of 500 to 700 meters and actually hitting a 30cm x 30cm target. How do you plan on aiming this launcher, laser sight or scope or both?

You may want to do some research on ballistics of actual real live ammunition rounds to comprehend how much velocity is required without out an elevation angle of 45 degrees to compensate for the drop at the distances you are referring to.

At 100 meters I believe you could possibly get away with and consistently hit something. And that to will still be a relatively high angle of elevation.

Unless you have a velocity of 3000 fps like an M16. (Note not exact figures, just approximation), that is what may be required for your 700 meter range.

Look up remington or winchester or other ammo manufacturer and research there ballistic information and see what bullet drops you get with different ammo sizes around the 22 caliber.

My deer hunting bolt action rifle (243 cal with 100 grain bullet) at 700 meters may hit your target consistently but a homemade launcher has way too many variables to obtain such a feat.

JSR where are you?
Give john a better explanation if possible than I can!

[USGF]

John,

If you can machine a steel mold, then you might use it as a cold forming die rather than a hot pour mold. Place a lead slug that is slightly larger than the finished projectile in the dies. Press together with a hydraulic car jack. The die needs an area where excess lead can bleed out. It may seem you could do more than 1 round at a time but try a 1 cavity die first. It sure is faster than casting. Esp if you can use ready made fishing weights as the starter slug.

I know you have no or limited access to a mill. It wil be difficult with a lathe only. Can you get a milling attachment for your lathe? Not great but better than not having any milling capabilities. Another option, you can contact Gismo on this thread:

http://www.spudfiles.com/forums/viewtop ... 486#247215

USGF