Ogive Radius

[williada]

Does anyone know the ogive radius for the tangent section in the nose of the Berger 7mm 180 grain Hybrid bullets? My old version of Applied Ballistics does not have it in the drawings. Thanks, David.

[bartman007]

Here is some detail I could find:

http://www.bergerbullets.com/pdf/Quick- ... Sheets.pdf

Enjoy.

[aaronraad]

Never seen anything official from Berger or any other source David.

If I was already making a 7mm VLD with a single secant ogive 18 radius and wanted to make a double ogive VLD...I'd run something like a tangent 9 until I was 0.001" to 0.002" under groove diameter into a secant 18 and see what it was like after some spring-back? Alternatively start with a tangent 6 and run it until I was twice the "local jacket wall thickness" under the groove diameter and then switch to a secant 18.

Are you trying to optimize the lead angle on the chamber throat like Sierra claim with their 7mm-183gr MK?

...where is the tip Sierra where is the tip???

[williada]

Aaron my old three phase tool and cutter grinder is about to come out of mothballs with a single phase replacement motor for where I live now. So yes, I want to play with a few throat reamer designs and optimize them for particular production bullets for use in F Class. Been down that track before, but bullets have changed since 2002/3 and I have not had the inclination to adapt as I have not been shooting competitively, just for entertainment and bag carrying for the other half these days at the local level.

I am still waiting for Berger to reply, so in the end, I will simply measure and average a few sample projectiles. Thank you to both you and Michael for your replies. David.

[williada]

Berger's reply was:

Hello David,


Thank you for contacting Berger Bullets. We regret that we are not able to assist you with this request since this is considered as proprietary information of our Hybrid bullet design. Please do not hesitate to get back with any of us with the Berger Tech. Team if we can be of further assistance in the future.


Looking for ammunition loaded with Berger Bullets? Ask me about ABM Ammo.


Kind Regards,
Bob Blaine
Technical Specialist
Berger Bullets Technical Support Team
techsupport@bergerbullets.com

[Longranger]

Aaron my old three phase tool and cutter grinder is about to come out of mothballs with a single phase replacement motor for where I live now. So yes, I want to play with a few throat reamer designs and optimize them for particular production bullets for use in F Class. Been down that track before, but bullets have changed since 2002/3 and I have not had the inclination to adapt as I have not been shooting competitively, just for entertainment and bag carrying for the other half these days at the local level.

I am still waiting for Berger to reply, so in the end, I will simply measure and average a few sample projectiles. Thank you to both you and Michael for your replies. David.

David, save yourself the hassle of a single phase motor refit and purchase a variable frequency drive. These can run a single phase input with a three phase output.

[williada]

That's good advice Longranger, but I got one single phase motor for nothing to do cylindrical grinding and the other main motor for half the cost of a phase converter which I had considered and believe are excellent. The machine's already apart and I am in the process of fitting it up. David.