I have a 14.5 barrel with PWS FSC556 that has been pinned and welded. I used the peel washers that came with PWS. I see that BCM uses the crush washer posted here.http://militarytimes.com/blogs/gearscout/2010/05/17/bcm-14-5-midlength-upper-receiver-group-w-permanent-flash-hider/
That would give the PWS a little overall length vs the peel washers what did you all do?
I wouldn’t worry about it at all, dude. It takes less time to install with a crush washer than a peel washer…if you were a manufacturer and had to put a 100 of these things together, think about how much time you’d save going with crush vs. peel washers?
That, plus the FSC556 is already 2.1" to begin with so theoretically, youre GTG even without a washer at all.
I built an upper using a DD 14.5 middy barrel and a pinned/ weld PWS 556 brake. Went with a 13" Troy TRX Extreme rail and matching flip up sights also. All I can say is that its tits… There’s almost no recoil at all with that setup. I highly recommend this type of setup.
No problems either way, the crush washer is a bit quicker way of doing things, but both are fine.