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"fastest bullet" 439 hits

Weatherby, on tests performed for the US military using 300 Weatherby mag or 378 Weatherby mag brass necked down to 22 cal., pushed bullets beyond 5000 fps.

Look up ballistics tables. Tiny fast rounds are used for plinking varmints. Fast bullets severely erode rifle barrels. If they aren't solid alloy they tend to fragment.

Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz3.pdf