Are they? I don't have ready access to "gun only" stats, but in terms of overall homicides, that's not the case at all. FBI stats for 2017-2019 (the most recent I could quickly find):
Year Black White Other
2019 55.9% 41.1% 3.0%
2018 54.9% 42.4% 2.7%
2017 54.2% 43.1% 2.6%
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