Outer barrel diameters

Hi all

Just wondering if all outer barrels are created equally? I know the different styles will vary in OD, but are the ID sizes all pretty much the same? What’s the average size for the ID of the outer barrels?


As far as am aware, the ‘standard’ size of the inner barrels outside diameter are around 9.5mm… So my guess would be most outer barrel inner diameter would be a loose fit like about 9.7mm or a bit larger?

The others might know more precisely :+1:

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Instead of creating a new thread I thought I’d wake the dead…

What ID of outer barrels have people come across? 14 and 16mm seem to be the standard but which are the most common? I don’t want to get a 14mm and have to bore the ID out.

And @Rattler wtf were you thinking when answering the op question :joy:

19mm seems to be the standard outer barrel OD but I’ve seen lots of different ID’s from 9.5mm to 17mm

@blek WTF are you talking about ?


Sorry rattler I always get you and calcifer confused… but thanks for your answer :+1:

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TF I thought I was going mad or madder :exploding_head:

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Their not. Most I think are about 19. But I do know my aug has a 17mm outer barrel. As to others not sure what they are

He is talking about the ID of the outer barrel not OD, no barrel I have is over 19mm OD

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My bad :man_facepalming: