Mags are often designed to hold rounds in multiples of 5, so ten, twenty and twenty five can be found for some guns. 3 round burst is common, so a rifle having a 3 round burst and a magazine in multiples of 5 is super normal. Many US military automatic rifles like the M4 also fire 3 round bursts. 20, 30, and 40 round magazines are available for the M4. French ain’t got nothing to do with it having non-multiples of 3 in all magazine sizes. Also, the FAMAS has an available 30 round magazine…which is divisible by 3.
Mags are often designed to hold rounds in multiples of 5, so ten, twenty and twenty five can be found for some guns. 3 round burst is common, so a rifle having a 3 round burst and a magazine in multiples of 5 is super normal. Many US military automatic rifles like the M4 also fire 3 round bursts. 20, 30, and 40 round magazines are available for the M4. French ain’t got nothing to do with it having non-multiples of 3 in all magazine sizes. Also, the FAMAS has an available 30 round magazine…which is divisible by 3.