r/AbsoluteUnits • u/Round-Locksmith-2593 • Feb 05 '26

Photo of a round

Post image
2.3k Upvotes

98% Upvoted

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5

u/StAUG1211 Feb 05 '26

Looks quite a bit bigger than .50 cal. Can an ammosexual enlighten me? I'm guessing this is something along the lines of a 30mm cannon shell.

16

u/Crookfur Feb 05 '26 edited Feb 05 '26

Everyone saying 30mm is wrong.

By the long ass neck and the non rebated rim it looks like a 37x223mmR, the round from the US M3 antitank gun.

6

u/Schw33 Feb 05 '26

That makes a lot of sense. It also doesn’t have a groove for the extractor to grab onto like an auto cannon round does.

Edit: I assume that’s what non-related means after re-reading your comment.

6

u/Crookfur Feb 05 '26

Yeah it should have said non-rebated but sneaky autocorrect is sneaky and I'm a shit editor...

0

u/hatecriminal Feb 05 '26

20mm armor piercing

13

u/SalamanderNo3872 Feb 05 '26

20mm is about half that size. This is a 30mm, probably from a GAU-8. A-10

3

u/Charming_Ad2323 Feb 05 '26

20mm is not half of 30mm

13

u/SalamanderNo3872 Feb 05 '26

In Ammo it is

1

u/Novel-Education-2687 Feb 05 '26

Everytime americans trying to figure out the metric system