Comments by "josh fritz" (@joshfritz5345) on "Sunngård Automatic Pistol: 50 Rounds in 1909" video.

@Janni069 I'm not sure about that, the M1 carbine had a fair amount of power to it. It packed more of a punch than most pistol cartridges of the day, including .45 acp. I think most of those stories are attributed to rather poor marksmanship, since the carbines were generally issued to second line troops with less training.
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Keep in mind .223 has a lot more projectile mass due to it's length. The round used in the sunguard is likely more comparable to .22
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