There's bound to be stuff in each box to interest people, my suggestion would be to split the boxes up into smaller bundles by type (AK, AR etc) as you've already done & be realistic with your pricing.
Try and display each bundle in the pics so the items are easily seen by buyers, you'll prob get messages for bit's n bob's so be prepared to sell off individual items & recalculate your price as things sell.
Is there anyone you can rely on to take bundles to game days to sell? a captive audience of airsofters are more likely to offer £10 here & £10 there just to get one item out of a smaller bundle.
Good luck.