The Firing Line Forums - View Single Post - weight vs. speed in terms of flight and terminal ballistics

**Aguila Blanca** · July 28, 2018, 11:38 AM

In a vacuum, speed would contribute more because, as has been noted, the basic forula is mass times velocity squared. So, twice the mass equals twice the energy, whereas twice the velocity equals four times the energy.

But, again as noted, bullet shape has some effect. In air, for a given bullet weight, a spire-point rifle bullet (like a 55-grain .223) will maintain velocity more efficiently as it travels that a hollow point bullet with a squared-off base, or (perhaps worst case) a wadcutter bullet (a "flying ash can"). This is why all ballistics calculators include a factor for the ballistic coefficient.

July 28, 2018, 11:38 AM	#6
Aguila Blanca Staff Join Date: September 25, 2008 Location: CONUS Posts: 18,477	In a vacuum, speed would contribute more because, as has been noted, the basic forula is mass times velocity squared. So, twice the mass equals twice the energy, whereas twice the velocity equals four times the energy. But, again as noted, bullet shape has some effect. In air, for a given bullet weight, a spire-point rifle bullet (like a 55-grain .223) will maintain velocity more efficiently as it travels that a hollow point bullet with a squared-off base, or (perhaps worst case) a wadcutter bullet (a "flying ash can"). This is why all ballistics calculators include a factor for the ballistic coefficient.