[supercat]

I believe the 30 rd mag is see thru.

I would think something that would be visible or perceptible to a shooter with a shouldered weapon would be desirable if it could be made reliable. For example, it should be fairly straightforward to include a counter which would be zeroed when the magazine was removed and would increment every time the action closed with a magazine installed. Even if the counter were electronic and had batteries that could go dead, a battery failure would not interfere with use of the weapon--just make it less convenient to determine how much ammo remained.

[murdocj]

The 30 round standard mag is semi-transparent. There has been talk of an electronic counter in the fancy sight, but as far as I know it hasn't gone pat the "talk" stage.

Pic of broken-down XM8 (with translucent mag clearly visible) at http://www.murdoconline.net/archives/001107.html.

I agree that seeing the ammo count without taking your eye off the bad guys would be a big plus.