Well, they are introducing another blaster called the A280-CFE, which seems to be just as modular. Like the A180, the modularity was hinted at by the accessories included with figures a while ago (I suspected it after noticing Cassian's blaster pistol had the same greeblies as his blaster rifle) and that was recently confirmed (and the blaster was named) by a display
Star Wars Launch Bay (
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Keep in mind the A180's assault rifle configuration has been seen with and without the stock, so I'm not sure if there's really three set configurations. Also, looking at this picture from Hot Toys, it looks like there might be two different collapsible barrel extensions, a smaller for the pistol and a longer one to turn it into a sniper rifle (
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Yeah, I was going to make a post about that. I'm almost certain the wear is from the stock (but I guess the holster could have made it worse), which suggests they based the model in Star Wars Battlefront on one of the metal hero props. This stock also explains why they messed with the back of the gun so much: they ground off part of the "lip" around the side of the gun, separating it into two sections, so that the stock could slide onto the back part, and they removed the rear sight, removed the safety lever, and ground off the "tab" below the rear sight sight so that the stock would be able to fit. Here's a stock (heh) WE Luger for comparison (
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I wonder if there's any other way the stock attaches to the back, because it doesn't seem like it would be very sturdy if it just slides on.
I'm pretty sure we will get to see the the attachments in action, because the costume on display
Star Wars Celebration Europe 2016 had this (
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I thought it was one of the weird two tube devices that Cassian's costume had for a while, but I just noticed that it's actually the A180's assault rifle mode attachment and collapsible barrel extension inside their own holster, which explains how Jyn carries around those extra attachments (I don't see the stock, though). Looks like they might be stunt versions, judging by the visible mold lines. Also note that the collapsible barrel extension is separate from the assault rifle mode portion.
That costume is the one she wears on Eadu, so that's probably when we'll see her use (which is what I was assuming, since it didn't seem right for her to use it on Jedha or Scarif). I think the closest we've gotten to seeing it in live action is still this Topps trading card from
Star Wars: Card Trader:
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I noticed that too, but, for some reason, the stud and the plate its attached to only show up sometimes. Here's a picture where it's not present (
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And here's one where it is (
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I'm guessing you can probably remove those screws and then easily remove the plate. I'm not sure what its for, though, since I don't think we've seen anything to suggest Jyn attaches a sling to it.