Testing the 'Welcome Back Cotter' 12ga Slug with Shrapnel Effect

Design and Construction of the 'Welcome Back Cotter' Slug

• 💡 The 'Welcome Back Cotter' slug, designed by Brian, is a 12-gauge projectile featuring 13 cotter pins, a stainless steel pin, and rubber bands for assembly.
• 🛠️ The components are cast in a clear epoxy resin, designed to be strong enough for firing but to break apart on impact, releasing the internal components.
• 🎯 The nose of the slug is concave, functioning as a hollow point that is intended to cause disintegration upon impact.
• ⚖️ The slug weighs 26.8 grams (approximately 413 grains).

Ballistic Gel Testing and Performance

• 🎯 The first test was conducted at 20 yards into wet catalogs, achieving an accuracy close to the point of aim at 1028 ft/s.
• 💥 Upon impact, the slug began to fragment around 2 inches in, with cotter pins opening like fish hooks, causing significant internal damage.
• 📈 Subsequent tests in clear ballistic gel showed increased velocities as the ammunition warmed up, with one shot reaching 1285 ft/s.
• 🔍 Fragmentation was observed consistently, with cotter pins spreading out and the penetrator core often exiting the gel block.

Performance on Various Targets

• 🛡️ A 30 lb lead plate was tested, with the penetrator core nearly penetrating the plate, suggesting good potential for penetration with slightly higher velocity.
• 🎯 Testing at 40 yards demonstrated impressive accuracy and penetration on a mild steel plate, creating a clean hole.
• 💥 A final test on ballistic gel showed a tremendous energy jump and full penetration of the core, with localized cotter pin spread and observed detonations within the gel.

Observations and Conclusions

• 📈 Velocity generally increased as the ammunition warmed up, with shots reaching up to 1370 ft/s.
• ⚠️ A key observation was the difficulty in achieving full expansion of the hollow point, which may have impacted fragmentation effectiveness in some instances.
• 🧩 Despite some challenges with expansion, the slug demonstrated good accuracy and penetration capabilities across various targets.