Airsoft Straight-Pull Bolt?

[Crapshoot]

Mods if this is in the wrong section then please move it.

I was just wondering if there are any made for gas, or even spring sniper rifles? Or have you ever seen a custom made one? I do not own a sniper rifle, but the question intrigued me, and it seems like a good idea.

[foxtr0t]

www.evike.com/product_info.php?cPath=21_48&products_id=37368

To my understanding this is a straight-pull bolt.