Jeff Siewert

Jeff Siewert is a recently retired ballistics engineer who has worked on ammunition in virtually every caliber between 0.17 caliber up to 8-inch howitzer. He has conducted studies on bullets, propellants, ignition systems, cartridge cases, fuzes, armor penetration, trajectory matches, radar data reduction, bullet-barrel interactions (including in-bore balloting and body engraving), and rifling design.

In small caliber, he has conducted studies on 0.177 & 0.22 Cal Airgun Pellets, 22 cal non-lead rimfire projectiles. In 5.56x45mm; case-chamber interaction for brass, polymer and aluminum cartridge cases and dispersion reduction on M855A1 as well as M856A1. In 25 caliber, he has evaluated “Bio bullet” stability and dispersion for remote inoculation of bison. In 6.8mm, he has conducted balloting and dispersion analyses for Next Gen Weapon System General Purpose projectile. In 7.62mmx51mm conducted engraving force measurements on military and commercial hunting bullets, as well as studies on barrel twist, rifling profile, and dispersion. In 8.5x63mm (338 Norma), he conducted a case-chamber interaction study to troubleshoot case failures. In 50 BMG, he conducted a structural investigation on the M962 (SLAP-T), and case-chamber interaction studies on the 12.7x99mm case. Lastly, he recently performed a design trade study on a 12 Gauge sabot slug for a major US sporting ammunition manufacturer, examining the aerodynamic performance and conducting a dispersion assessment.