So I've been ready to form 1 a lower I just got for a couple weeks almost but I'm unsure of a few things.
First being the caliber listing. I intended on using several different uppers but read that I can only put one in the box. What do I do if I want to use a 300BO upper later on?
Also, regarding barrel length and overall length questions - what do I do with that? Someone elsewhere said you can send a letter to the ATF later on saying you intend on putting a different length upper on the lower and they'll send a letter back allowing it?
And how am I supposed to measure the OAL with a collapsible stock? Shortest position to end of muzzle device? Longest? It's almost like they want me to assemble it illegally to measure it so I get it on the dot measured right.
I was going to file the stamp now and then build the upper while I wait but without the measurements I don't think I can even file the stamp? Has anyone else done it this way? How did you approach doing this?
Any help is greatly appreciated - I really want to get on this before the flood of new form 1s make the backlog a year long due to the pistol brace issue.
Edit: also what about changing muzzle devices later on? Is this a no no or will this require a letter to the ATF beforehand again?
First being the caliber listing. I intended on using several different uppers but read that I can only put one in the box. What do I do if I want to use a 300BO upper later on?
Also, regarding barrel length and overall length questions - what do I do with that? Someone elsewhere said you can send a letter to the ATF later on saying you intend on putting a different length upper on the lower and they'll send a letter back allowing it?
And how am I supposed to measure the OAL with a collapsible stock? Shortest position to end of muzzle device? Longest? It's almost like they want me to assemble it illegally to measure it so I get it on the dot measured right.
I was going to file the stamp now and then build the upper while I wait but without the measurements I don't think I can even file the stamp? Has anyone else done it this way? How did you approach doing this?
Any help is greatly appreciated - I really want to get on this before the flood of new form 1s make the backlog a year long due to the pistol brace issue.
Edit: also what about changing muzzle devices later on? Is this a no no or will this require a letter to the ATF beforehand again?
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