Contents - Index

Calculate Ogive Dimensions


This module may be used to calculate six distinct ogive dimension values from two or more existing ogive dimension. 

The basic procedure is as follows:
A. Determine the dimension value you wish to calculate and then click the Enter Values button under the dimension heading.  The entry windows for the values needed to calculate the desired dimension will change from gray to white. 
B. Enter the values in the opened windows.
C. Click the Calculate button under the desired dimension heading.

First click the Clear Values button and then click the Enter Values button. 
  a. If the meplate is a round nose design. a message will appear suggesting a standard dimension ball end mill diameter that will approximate the existing round nose dimensions. You may accept the suggested dimension or select a larger or smaller standard diameter dimension from the drop-down Ball End Mill Dimension List.
  The existing Nose Diameter, Ogive Radius in inches, Ogive Radius in calibers and (if selected) the ball end mill diameter will be entered into the edit windows.
   If you wish to simply calculate the ball end mill diameter needed for the existing dimensions, click the Enter Values button under the Ball End Mill edit window to open the value entry windows needed for the calculations, enter the existing values or edit as desired and then click the Calculate button under the Ball End Mill edit window.  

  b. If the meplate is flat, the existing Nose diameter, Ogive Radius values and the meplate radius values will be entered. use the lower set of buttons indicated by the label titled Flat Meplate Calculations > > to select values and calculated the desired dimensions.  Use the Send Bore Ride Length & Tip Dia. to Calculations button to enter the calculated values into the design record.


After selecting a standard Ball End Mill diameter, proceed as follows:
1. Either use the existing pre-entered values or edit as desired

2. Click the Enter Values button under the Meplate Radius heading and then click the Calculate button.

3. Click the Enter Values button under the Ogive Length heading and then click the Calculate button.

4. Click the Enter Values button under the Tip Length heading and then click the Calculate button.

5. Click the Enter Values button under the Nose Length Ogive L. + Tip L. heading and then click the Calculate button.

6. If you are satisfied with the calculations, click the Send Bore Ride Length & Tip Dia. to Calculations button to enter the calculated values into the design record.

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If designing a flat meplate bullet with a nose diameter larger than the bore diameter for a specific chamber, you can calculate an ogive length and ogive radius to just touch the lands at the point where the lead meets the bore diameter in the barrel chamber.
Click the Enter Values button indicated by the label titled Calculate Ogive Length and Radius from  a flat meplate to a specified  bore diameter- - - - - - > 
Enter the Bullet Nose Diameter, Bullet Meplate Diameter, Cartridge Overall Length, the distance from the base of the chamber to the point where the rifeling leade ends at the bore diameter, and the Cartridge Case Trim-to Length.
Click the calculate button.
The software will calculate the distance from the case mouth to the ogive base, the ogive radius, the Out of Case Bullet Nose Length,  the slope of the ogive at the contact point and the angle of the radius at the contact point.

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