Two questions about these rifles

[MattyDienhoff]

I have a couple of questions:

http://www.imfdb.org/images/1/1b/SIG550.jpg

Is that a 20 round magazine? It looks too small to be a 30 rounder to me, but I'm no expert and I'd like to be sure because I'm making a mod for S.T.A.L.K.E.R. that changes how the weapons behave, and the SIG SG-550 model in it has a magazine of that size, but holds 30 rounds. I want to be sure that's wrong before I change it.

http://www.imfdb.org/images/b/b8/ColtM177E2.jpg

What is that on the end of the barrel? Is it a muzzle brake?