Question for Bill Jurens -- nose length and CRH estimate

[marty1]

Bill:

I’m trying to back calculate velocity drop for this particular projectile. To that end, I am interested in your estimate of the nose length and CRH.

Thanks

[Bill Jurens]

K. I have the photo here and should have something by Monday.

Bill Jurens

[marty1]

Thanks Bill.

[Bill Jurens]

My measurements suggest that this is a 3-part secant-ogive design made up of a 6.5 c.r.h. ogive superimposed upon a short cylindrical conical frustrum, which is in turn blended into the cylindrical body by a small radius at the secant point.

The physical ogival radius for the most forward 5/6 or so of the ogive would appear to be -- as stated above -- about 6.5 cal. The head height, measured from the secant point to the tip of where the nose would actually be if it were not somewhat distorted, would appear to be about 1.78 calibers, which is the proper head height for a 3.5 c.r.h. tangent ogive.

This might be best described as a 3.5/6.5 c.r.h. secant ogive.

The cylindrical body sticking out of the base is interesting, and is presumably some sort of a fuze. It probably would not have affected flight dynamics very significantly.

Hope this helps...

Bill Jurens

[marty1]

Thanks Bill. Any opinions on projectile type -- I'm thinking of running with a G7 drag function.

The protrusion on the back side of the projectile is the tracer element.

[Bill Jurens]

Type 7 looks like a pretty good match to me.

Bill Jurens

[marty1]

Danke