0824160110a2 August 24, 2016 at: 1500 × 844 In: Future Firearms Ammunition Technology 008: Plastic-Cased, Telescoped Ammunition – Lightening the Load, Pt. 4 Next → Polymer-cased telescoped ammunition, left to right: .38 cal. Dardick Tround, 5.56×30 Hughes Lockless, 5.56×45 Steyr ACR flechette.