5.56 mm GP 90 drawing needed


#1

A friend of mine would need a drawing of the swiss 5.56 mm GP 90 cartridge. Ballistic data would be helpful too

Thanks in advance for any help


#2

If you use a G7 form factor of 1.0735 you can replicate the ballistics of 5.6 mm GP90 very well. Bullet weight is 4.1 g and muzzle velocity is given as 905 m/s in the Swiss field manual.
The Swiss firing table uses their standard atmosphere, which has a density of only about 94 percent of ICAO standard. Listing velocities here would therefore not be of much use.
There is a cutaway drawing of the bullet in most books by Beat Kneub├╝hl, but it has no dimensions (ogive radius etc.).

Note the Swiss call it 5.6 mm, not 5.56 (actually they write it as 5,6).


#3

i7 FF for the GP 90 is given as 1.091 here.