The "Trapdoor" Springfield: From the Little Bighorn to San Juan Hill

Intended to replace the proliferation of different small arms fielded by US forces during the American Civil War, the “Trapdoor Springfield” was designed in 1865–66 by Erskine S. Allin.

Using metallic cartridges, it could be loaded in a single action, increasing the number of shots per minute as much as fivefold. The new weapon quickly proved its worth in two separate incidents in August 1867: small groups of US soldiers and civilians armed with the trapdoor repulsed numerically superior Nat...