Pinnacle Mountain Summit

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Edging, open-handed, and 550 vertical feet later: a view of Arkansas 300 from the top of Pinnacle Mountain (altimeter reads 1120 feet):

I'm still not convinced of the economic advantages of handloading. Dividing the savings by the time to clean the brass, to assemble & organize the components, in addition to the reloading itself, I'm paying myself less than minimum wage. But that's more than I get for recycling other materials, and it allows me to tailor the recoil and muzzle energies of my 40 auto and 38/357 revolver.

The eastern portion of Lake Maumelle:

To calculate the muzzle energy of the bullet, begin with the formula for kinetic energy (the energy it takes to stop a moving object) and wade through the screwy unit conversions:

KineticEnergy = 0.5 x Mass x Velocity^2
MuzzleFtLbs = 0.5 x ( BulletGrains / 7000 ) x ( MuzzleFPS^2 / 32.174 )
            = BulletGrains x MuzzleFPS^2 / (14 x 32174) 

The kinetic energy of the recoiling firearm begins with the formula rearranged to apply the conservation of momentum (and chemical mass) to the system, which includes the mass of the gunpowder as a gas traveling at 4700 fps:

RecoilFtLbs = ( MassFirearm x VelocityFirearm )^2 / (2 x MassFirearm)
            = ( BulletGrains x MuzzleFPS + PowderGrains x 4700 )^2
              / (2 x FirearmLbs x 7000^2 x 32.174) 

Increasing bullet mass, therefore, increases recoil energy faster than it does muzzle energy -- because the recoil energy depends on the mass squared. (For shotgun recoil, use the weight of the shot and wad in place of BulletGrains.) Changes in velocity equally affect both energies. And practical trade-offs between high-velocity over-penetration and heavy-mass ricochet now come into play; however, these are beyond the scope of this text.

The West Summit trail is far less vertical, a rocky staircase leading down to the picnic area:

Last year I saw a roadrunner here, perhaps looking for a snake. Indeed, the year before that, I found a shed rattlesnake skin at the park's boundary on the Ouachita Trail, which runs over 220 miles to Oklahoma.

Because of its high velocity, the powder's load contributes significantly to the recoil energy. High-efficiency powders help minimize the contribution while maintaining practical muzzle velocities and energies. (The recent .338 Federal rifle cartridge takes this concept to the next level with its case design.) Looking through the load data in the Speer Reloading Manual 13, two promising powders appear to be TiteGroup and Power Pistol.

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Last modified: 11/3/2006