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AR15.COM
7/31/2015 7:07:09 PM EDT
I posted this in the HK forum but also want to post here so I can get a quick answer. I need to know the size of the opening on a factory MP5 BFA. I have a small film shoot we are working on tomorrow and the MP5 got added to the list at the last moment. I have never run blanks through one so I am making a BFA for it today and need to know a size for the aperture. Thanks in advance!
7/31/2015 10:49:26 PM EDT
[#1]
It is a small hole. I would guess not much bigger than 1/8".
7/31/2015 11:18:47 PM EDT
[#2]
The size of the hole varies with what blanks you are using and barrel length. If you can hide a set screw in the blank firing adaptor you can drill different size holes in different set screws and try different sizes until you find what works with the blanks you are using.