Sterling clip retaining mechanism question

[Ducati]

A question for anyone that has a real sterling clip/magazine receiver:

 

 

What does the device on the side of the clip do? I'm referring to the gizmo in the north west portion of the picture below.

 

What does it do? (I'm assuming that it's aids with alignment of clip to the receiver such that the rounds can be fed into the bolt properly)

How does it work?

Does it do anything other than butt up against the receiver?

Is it sprung is some fashion?

 

 

Thanks in advance

 

 

[TK bondservnt[501st]]

it's a stop. it allows the clip to be inserted to the proper depth in the magazine well.

[ObiHahn[TK]]

On your pic, the magazine endcap sits the wrong way around, btw. In the hole, there should be the round "nipple" thingy that keeps the endcap in the locked position.

I'm a bit surprised it even fits on the other way round due to the slight taper of the magazine. On mine, it only fits the right way.