re: Are there really 300 mass shootings per year in the US?

You're not serious.

From the bureau of justice statistics:

quote:

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Of the nearly 3.7 million violent victimizations committed
against white victims during 2012-15, a total of 57% were
committed by white offenders, 15% by black offenders, and
11% by Hispanic offenders. Similarly, the majority of the
850,720 violent victimizations committed against black
victims involved black offenders (63%), followed by white
(11%) and Hispanic (7%) offenders. Forty percent of violent
victimizations committed against Hispanic victims were
committed by Hispanic offenders, while white and black
offenders each committed 20% of victimizations against
Hispanic victims.

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Violent victimization includes rape or sexual assault, robbery,
aggravated assault, and simple assault.