One thing that has always been consistent about light, fast bullets is the inconsistency of the wounding effect. Once upon a time, the 220 Swift was idolized by gun writers as producing spectacular kills on game up to deer size. Time and experience proved them wrong.
The 5.7 would be a wonderful plinker but as time goes on the results in defensive situations will likely be similar to those of the 220 Swift on big game, very inconsistent.

Glockin' Bob
I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them." -- Thomas Jefferson
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