<b>Thompson Autorifle Model 1921</b> (top), submitted by Colt's Patent Fire Arms Manufacturing, Inc., for the 1921 trials used the Blish principle of metal adhesion, used in the famous Thompson submachine gun ("Tommy Gun"), as developed by Gen. John T. Thompson. This weapon was preceded by a similar model the year before. In trials in 1921 against the <b>Garand Model 1921</b> (bottom), the Thompson rifle performed poorly. Later efforts by Colt with rifles using the Blish system were similarly disappointing.
The <a href="https://en.wikipedia.org/wiki/National_Park_Service" class="extiw" title="w:National Park Service">National Park Service</a>
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