Non-existing or unknown force!!??

[bosveldjag]

Has anybody ever heard or known anything about the following:

How the whole question of stagnation pressure works against the stability of the bullet .......?

Your comments and input on this will be appreciated.

[Rocky Raab]

According to a source I found, "Stagnation pressure is the pressure a fluid exerts when it is motionless."

Even if we assume air as a fluid (partially correct), I cannot see any application to bullet ballistics because the "fluid" is always in motion around the bullet, in a relative sense.

There is one area where "stagnation" occurs in bullet flight, however. It is the area at the base of the bullet where the moving air rushes in around the bullet base, creating a tiny pocket of extreme turbulence. (Think of a boulder in a stream. The spot just at the downstream surface of the rock where the water really swirls is the stagnation zone.)

The stagnation zone creates axtra drag. Making that zone as small as possible improves the drag coefficient. That's why boattail bullets were developed: it minimizes the stagnation zone for any given bullet diameter.

But the stagnation zone has no effect on stability that I can discover.

[bosveldjag]

Can you please quote the source you found on this definition of 'stagnation pressure'?

Not that I doubt it, but for future reference if needed.

[Rocky Raab]

Actually, I just typed it into Google and got a couple dozen definitions. Be my guest.