Here are pdf scans of a year 2000 era manual for:
the ACCURACY DEN *I.C.C. UNIT
*(Internal Concentricity Comparator)
Ultrasonic Metal-Mass Detector
“The Vern Juenke Machine”
Original US LETTER size format ;and
VernJuenke_oringal LTR size version
resized A4 format
VernJuenke_resized LTR to A4 version
See the Short Range Benchrest Bullets page for new calibres.
Pricing has been updated on the G7L series projectiles webpage from the previously price listings set in 2012.
Changes allow for the raw materials costs and the AUD exchange rate.
For something a little bit different here is a link to the OpenRocket source download. It’s a Java based program. Don’t expect exact ballistics software but you cna construct your own designs and use the Component Analysis function to see how changes affect the drag etc.
So here is a link to download the original MS Excel spreadsheet for Nose Cone Design.
I use a modified version myself to plot shapes that resemble long range target projectiles. If I can do it I’m sure those of you some knowledge of spreadsheets can come up with their own modified version. Follow the instructions and enjoy!
So if you’ve managed to magnify the outline of your ogive, effectively you can calculate the radius by measuring the meplat to the shank/ogive intersection. This will become your chord length W.
The Sagitta of the arc or height (H), is measured perpendicular from the midpoint of the chord W.
For double or multiple radius ogives there will be multiple chord lengths measure. Note also this method only works with ogives using a tangent and secant radius. The larger your outline is magnified the more accurate your measure will be, useful for those of us without an optical shadowgraph comparator or other such metrology equipment. Remember though you may have to contend with the parallax error depending on how you capture your image outline.
(link to Math Open Reference.)
Given an arc or segment with known width and height:
 |
where: W is the length of the chord defining the base of the arc H is the height measured at the midpoint of the arc’s base. |
7mm.com.au facebook link to the winner announcement!
Congratulations to Robert Alman, the winner of the Antipodean Industrial Give Away.
Here is a link to the projectile Give Away promotion with 7mm.com.au. Follow the link below for the entry form.
Antipodean Industrial Give Away
Here is the link to an interview by Michael Bell with Ken Melgaard from CopperHead Bullets discussing bullet swaging.
