Bullet Question.....

[ZombieKiller]

Are "Truncated Cone" and "Flat Nose bullets the same?

Thanks in advance for the help.......

[mike100]

No, flat nose bullets could have a classic rounded ogive curve to the bullet like most do, but the truncated cone has flat angled sided like a dunce hat(triangle) cut off near the top (truncated into a small flat).

Picture here of bullet next to mould

[ZombieKiller]

I'm glad I asked....thanks again for the help.....


While I'm at it- can truncated bullets be used in the load data for the flat nosed variety? Or will that change the pressure and such?

[Fjold]

I'm glad I asked....thanks again for the help.....


While I'm at it- can truncated bullets be used in the load data for the flat nosed variety? Or will that change the pressure and such?

The answer is.................................. maybe.

It depends on the bearing length and jacket material of both bullets. In similar weight bullets I would use the starting load for either and work up slowly. I would not substitute bullets with maximum or near maximum powder charges.

[ZombieKiller]

Sweet......thanks again......I love this place on the web...it rocks...

You all rock....and its not the meds talkin. You rock.

[mike100]

9mm was originally made with that truncated cone design. I actually have that mould as I showed above in that link (my uncle gave me a 40 year old one). The Lyman manual has load data for it. in lead, that particular bullet had similar load charts as a regular round lead 124 gr bullet, possibly a bit higher.

I made a couple of hundred of them, but haven't shot it yet. My theory is that they will shoot ok because the mass of the bullet is set back toward the rear and the centrifugal forces the rifling put on it will be less than a fatter round ball design. we'll see...