Re: Does anyone make Long Range SOLIDS in a heavy weight .338 cal.....
None of my designs are bore-riders. There is a maintenance issue entailed with the use of these, which is entirely circumvented by an engraving-band bearing surface configuration.
A 1: 10" exit-twist falls just outside of the rate necessary to take advantage of the copper density value. For example, the 265 grain, 6.0 caliber, banded copper solid essentially matches the 300 grain Scenar in trajectory with equivalent muzzle velocities, falling .2 mils lower at 1,200 yards (~8.4"). It requires a minimum 1: 9.5" twist however, and barely fits into available magazines even in the Norma Magnum loading. Given that the ZA338/6.0-Cu costs 40% more than the Lapua, the only justification for it's existance is extremely consistent, single digit ES, zero fouling, high accuracy, and superb expansion properties of the hunt version.
It is only when a 1: 8.0-8.5" twist is used that the ZA338/6.0 can surpass the 300 grain Lapua in BC by taking advantage of 3,500 fps muzzle velocities, and at that point it makes much more sense to move up to the 6.5, or 7.0 caliber ZA. In this region, copper has the perfect density to properly fill optimal aerodynamic forms.
Last edited by noel carlson; 05-29-2009 at 09:47 AM.