BRASS 12 gauge dummy rounds / snap-caps / fake bullets. Looks like the ones used by the US Army during WWI and World War Two in the Model 1897 Trenchguns.
ST Action Pro 12 Guage Dummy Rounds - Full Review
12 GAUGE 2 3/4 SNAP CAPS DUMMY TRAINING ROUNDS SET OF 8 SAFETY
AXI Brass Dummy Rounds – 5 Pack
12 Gauge Shotshell Pack replicas and snap caps by spearmountain
3D Print Nation 380acp Brass Snap Caps Dummy Rounds
A-Zoom Action Proving Rimfire Dummy Rounds - .22 LR, 6pk [12208]
Dummy Rounds / Snap Caps / Fake Bullets - Page 3 of 35 - Snap Caps Dummy Rounds
Inert Dummy Shotgun Shells & Cartridges
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