Help ... 
I'm looking for the ATF letter that specifically states a new AR 15 lower with buttstock attached does not become a long gun until a greater than 16" upper is attached - that an AR 15 with buttstock attached is 4473'd as "other" and can be assembled as a handgun outside CA of course.
Someone on another forum (GB) ended a thread with "an AR 15 with a buttstock is automatically a long gun" and I'd like to post the correct info.
I found the T/C letter, but one's been posted here regarding the AR specifically.
Thanks

I'm looking for the ATF letter that specifically states a new AR 15 lower with buttstock attached does not become a long gun until a greater than 16" upper is attached - that an AR 15 with buttstock attached is 4473'd as "other" and can be assembled as a handgun outside CA of course.
Someone on another forum (GB) ended a thread with "an AR 15 with a buttstock is automatically a long gun" and I'd like to post the correct info.
I found the T/C letter, but one's been posted here regarding the AR specifically.
Thanks




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