What are these parts for?

rbthntr64 said:

Those are the crosspin locks for the original FCG. They are not used in the semi builds. Here is a pic of a friends rifle from New Zealand. You can see the pin lock inside the receiver. They do not have the restrictions there that we have here. He can switch between the semi fcg and the original. It requires a special license though.

Click to expand...

So, we use e-clips in lieu of these then?

If I'm seeing this right, all it does is tilt up and out of the way to let the pins out? I'm assuming the piece on the front acts as a detent and goes into a recess somewhere on the inside of the receiver then? Since the pins are in the same place whether it's using the original FCG or not, why wouldn't we put these in to hold the axis pins on a semi build?

If I could get some more info on how these are installed, I wouldn't mind adapting it to my build. I can't see why having a pin lock would be a big deal, I'm building an SBR anyways. Are there two in each gun, or did my kit just come with two. They'd have to be installed asymetrically which seems kind of weird, not to mention a little over-redundant to have two.

actually I think I just figured out why we don't have them. The "shelf" in our receivers here aren't milled out as far so they won't accept the auto trip lever, that looks like it blocks where the pin retainer would tilt. I don't think I'll be doing any machining in that area :neutral:

I might be able to modify the pin lock though...definitely more work than it's worth.

I see why all of ours come with e clips now.