“Iron Man” backpack

A 500-round backpack for the M240 machine gun:

[youtube laqGgPWyp4k]

A few ideas promptly suggest themselves. First, integrate this into the LockMart HULC exoskeleton:

[youtube KU95h6YCUuM]

And then replace the standard M240 with a Knight’s Armament Chain SAW:

[youtube W2H2peoX174]

Giggity!