Cutting a thread into flutes of barrel

[Ginga]

Hi

3 questions:

1. I have a 243 finnlight and want to shorten the barrel to 18 inches (or less) and put a Dan Can on it (Gen 4). this will require cutting a thread deeper than the flutes. Will this mean going too deep into the barrel and i get barrel expansion and potential loss of accuracy (or is this bullsh*t?).

Dans suppressor is 80 mm ahead of the barrel so cutting 50mm gives me a net gain in length of only 30 mm. I'm not worried about a bit of velicity loss and the suppressor will be a permanent attachment so couldn't care less about the flutes going to the end of the barrel.

2. Do you think their will be enough "meat" left at the thread end of the barrel to rebarrel to 7 08 and not end up having very little barrel left? (hope that makes sense!)

3. Will a 7mm suppressor (in preparation for a rebarrel) adequately suppress the 243?

Cheers

Tom