Is 5000 FPS obtainable

[jb77]

Bill I believe that round has fins that stabilize it once the sabot seperates.

 

[CatShooter]

This subject has been discussed and cussed more than once on this and other Forums. It always bring to mind a question that I have - one that no one seems to be able to answer.

Exactly how fast can a bullet be accelerated through a rifled barrel with today's powders??? Its always been my understanding that simple physics dictates how fast expanding gasses can accelerate and it takes special techniques, such as squeeze bores, to exceed that limit.

Anybody????

Ray

The upper limits, using solid propellants, is in the neighborhood of 6,500 fps. This is using cartridges where the propellant weighs more than 4 times the bullet weight,100 grain bullet, 400 grains of powder.

It reaches this limit because after that, you are adding more powder to puch out the weight of the powder gases, and the weight of the bullet becomes inconsequential - at 1,000 grains of powder, you are pushing out 1100 grains of stuff, or which only 10% is bullet weight... as you increase the powder, you decrease the expansion ratio, you add more and get less.

The next step was done by the US Navy at Crane - they developed a two stage Helium gun that reached 25,000 fps, and it was able to do so because Helium weighs virtually nothing, so the weight of the projectile was the only thing that was being pushed.


.