Very Low Drag Bullet design / turned solids

[Romeyo]

Hi Folks!

I recently really enjoyed reading Brian Litz' book "Applied Ballistics for Long Range Shooting" and really got interested in the part about bullet construction and its influence on BC.
I did some research myself and came across nose cone desings that follow mathematical equations like sear-haack, Von Karman and so on...
Even different tail types that reduce drag more than conventional boat tails.

I would really like to be able to get all the information to design very low drag bullets and turn them from solid brass or copper. I don't just want to copy current designs. Has anybody recommendations on books that cover this topic or any sources on the web?
I'm not afraid of mathematics as long as I don't need some kind of NASA super computer to do the calculations...

I know that I won't be able to create a "hyper low drag" bullet without proper testing, research and so on, however I would like to learn about all that in more depth than it's explained in Brian Litz' book.

thanks in advance

romeyo

 

[BryanLitz]

Romeyo,

See:
Amazon.com: Modern Exterior Ballistics: The Launch and Flight Dynamics of Symmetric Projectiles (9780764307201): Robert L. McCoy: Books

Don't forget to print the extensive corrections sheet:
http://www.dexadine.com/download/mccoy04.pdf

McCoy goes into much greater depth on projectile drag. If you have a lathe to turn your own solids, then you have the flexibility to try many variations. Squeezing the jello, converging and optimizing on a shape is much easier with lathe turned shapes than with swaged bullets because of the expense of creating new dies.

I hope you make some 'hyper low drag' bullets and share your results!

Good luck!

-Bryan

 

[Romeyo]

Thank you for the recommendation Bryan! And sorry for spelling your name wrong...

I call a lathe my own... unfortunately it's just a manual one.
However, the company a friend of mine works got a cnc lathe. I'm able to do CAD-modelizing so the only problem would be aviability. Those machines typically don't stand around unused all day long ^^ But he told me it should be possible.

I'd also need some more eqipment for proper testing and since I'm a stundent getting together all the money might take a little while.
So I thought reading and learning as much as possible would be the best thing to do while watching account balance increasing...

Of course I will share results if you wish to, but don't expect them within the next few days ;-)

regards
Romeyo

 

[3875XLN]

We have made extremely high BC solid bullets in Finland. That is .30cal bullet, low weight and high BC. It´s possible to send 3600fps from 300 Lapua Magnum.
www.finsolid.com

 

[TargetTerror]

We have made extremely high BC solid bullets in Finland. That is .30cal bullet, low weight and high BC. It´s possible to send 3600fps from 300 Lapua Magnum.
www.kokeilutarvike.com

>.6 BC out of a 160 grain .30 cal? You guys need to bring those across the pond!

 

[Movin]

This link has good information with a .8 BC 30 cal, and other good bits of info on the web site.
GS CUSTOM BULLETS - Specifications for use
Also search a little about Noel Carlson on this web site and Snipers Hyde.
Search viking bullet from over the pond.

 

[Romeyo]

I checked those out (Vikings by Lutz Möller, Germany) , seem to be pretty impressive with an G1BC of ~1.54... however, it's calculated and not measured, and no note about what velocity band it's true for...

.375 Chey Tac Cartridge and Bullet

But as said, I would like to know "all" the basics about projectile drag to be able to design a superb performer myself, and not just copy current designs.
It's not just having a bullet with exeptional ballistic performance that interests me, it's also the knowledge of creating such a bullet... the how and the why...

romeyo

 

[Movin]

Good luck getting the perfect shape such as sear-haack, Von Karman to load and shoot as expected. That long boat tail displaces powder and is harder to seal in the barrel. When it leaves the muzzle the blast around the bullet tends to destabilize the bullet.
Check out the corbon web site. Rebated boat tails may be the best of both worlds. Banded bullets seem to seal better in the bore. Again, talk to Noel Carlson, he is well educated in this area and likes to push known boundaries. Where you are headed may need new propellants, new barrels with different metals, coatings and twist profiles. Ballistics and terminal performance are fascinating!

 

[Romeyo]

Good luck getting the perfect shape such as sear-haack, Von Karman to load and shoot as expected. That long boat tail displaces powder and is harder to seal in the barrel. When it leaves the muzzle the blast around the bullet tends to destabilize the bullet.

Maybe inline EDMed break holes would be a good way to decrease muzzle blast that could affect precision especially on long (boat) tails. Maybe some kind of muzzle break that can be screwed over that holed tip of the barrel would help reduce recoil even more since a couple of holes would likely be to less to reduce recoil on larger calibers.

Check out the corbon web site. Rebated boat tails may be the best of both worlds. Banded bullets seem to seal better in the bore.

I think driving band bullets would be the way to go anyway since solids would cause more friction and barrel wear without them.


Again, talk to Noel Carlson, he is well educated in this area and likes to push known boundaries. Where you are headed may need new propellants, new barrels with different metals, coatings and twist profiles. Ballistics and terminal performance are fascinating!

Yeah, they really are! I just need to refresh my math skills a little bit ^^ But as long as you see math as some kind of powerful tool and not just hate it it should work...

romeyo

 

[3875XLN]

Finsolid type 4450 cal338 range 300 meters group of 5.
www.finsolid.com