Mine took just over 10 months with a form 4. I've been told a form one gets approved faster for some reason but have not done another one yet.
Electronically Filed (EFiled) Form 1s average slightly over 30 days.
Much less work for the ATF as all the data is entered by the applicant.
Most EFiled Form 1s do their own pictures as JPEGs and do their fingerprints themselves using ATF supplied cards (free) and a cheap ink pad.
The tax stamp is emailed to you as a PDF that you can print out instead of waiting for the ATF to mail a paper copy in a paper Form 4 transfer.
30 days sure beats 6-12 months.