Comments by "Spring Bloom" (@springbloom5940) on "10mm is the Best Millimeter: the Colt Delta Elite" video.

Here we go again 😒 The primary reason FBI abandoned the 10mm, is because the Delta Elite was the only service gun available and it cost close to $1000, in the 80s. As noted, the guns were falling apart, so they started using light loads - 'FBI Lite' or as USMC called it '10 Whimpy'. That lead to the 40(which is among several reasons I hate Glock), which lead to an even wider problem of manufacturers simply converting their 9mm frames to 40, which caused them to wear out unacceptably fast. The 40 got a bad rep early on, because of that. TL;DR its not because the trainees 'couldnt handle it', its because they couldn't get guns that could.
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But it has atrocious ballistic coefficient, only slightly better than a roundball. Theres a saying about the 45, that it wont penetrate warm butter. We are talking about a FMJ that often doesnt exit the body.
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