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I'd be interested in seeing a pic of a dab of H110 next to N110 for comparison on grain type/size if you can make yourself do it.. I'm leaning that direction but haven't found any N110 locally. I'm not huge fan of metering on the H110.

N110 on top

H110 on bottom

IMG_2149.JPG
 
Oddly enough, this isn't actually true. When you're dealing with subsonic bullets, you're not dealing with any nose pressure drag (shock-wave) as such your drag function becomes a function of the surface area that's exposed to the air stream. On a .30 cal long ogive bullet.

View attachment 312307
Here's something the germans did in WW2 to work with the L31 suppressor for the MP40, it's a heavier weight bullet with a similar form factor, but a rather noticeable tail sticking out the back.

In a design similar to this, the whetted surface area would be lower, due to a transition from laminar to turbulent flow where there is a transition from the skin to the back of the bullet. However these were 9-gram bullets since they were "eisenkern" (iron core) which was cheaper than lead, which gives it a weight of about 140 grains.

The other thing that's interesting to this conversation, a 9mm has an approximate parabolic ogive, which is actually almost ideal for a sub-sonic projectile. (there's a table on the "nose cone" wikipedia page) Nose cone design - Wikipedia, the free encyclopedia

By comparison, the tangent or secant ogive rates as terrible just about anywhere it's tried. If you look at some of the modern missile designs (SLBM's especially) they use aerospikes as a way of moving the shock and friction drag forward of the main cone. But this kind of technology isn't really practical in small arms designs.
Great post, iff'n I ever go to he dark side of 300BO, I will refer back to this.
Physics makes the world go round. :D
Shock wave comes into play with bullets, jet engines, rockets, burners and hull design. I don't think much about it with bullets, but have been forced to deal with it in burners and hull design.
A pretty cool video explains the J58 engine of the SR71 Blackbird -
& how they dealt with shock waves :
 

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