This model is also sold as a complete rifle, supplied with two 50-round P90 magazines.

AR-15/M16-based STANAG magazines can be used to catch spent casings by taking out the feed lips, spring and follower.

[7] Unlike the standard AR-15 configuration which uses a gas-tube system, the AR-57 cycles via straight blowback[broken anchor].

[8] A fully automatic version exists and was marketed as a competitor to the P90 and other personal defense weapons.

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