Is it just me, or does that look like the spring that goes under the rail lock? I'd have to agree with the other two who I realize just beat me to it.
You are correct, that's the N-Strike tactical rail spring.
pepperach: I think you misread a mod write up. I remember reading that someone said he got good results by
ADDING the rail spring to the stock catch spring,
NOT by replacing.
The problem is that the spring isn't even long enough, that's why you don't here the click, its not even pushing down on the plunger rod. It's impossible for the catch to engage with that spring in it.
Edited by TantumBull, 02 October 2008 - 10:37 PM.