Both the Sten and MP40 have a much longer bolt travel than the UZI. The UZI's telescoping bolt allows for shorter travel, making it the least "clunky" of the three to fire. All three of these guns also rely on advanced primer ignition to somewhat mitigate the slamming home of their bolts. The Thompson relies on the shear weight of the bolt to fire the cartridge and has the least bolt travel of the lot. In the 1921 and 1928, the Blish Lock provided friction slowing of the bolt. The M1 and M1A1 eliminated the Blish Lock, but had a heavier bolt to make up for the Blish's slowing action on the bolt.
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