Quoted:
Hey everybody,  I've got a few ?'s about filing for a SBR:

1. I purchased a Rock pistol lower about 7 mo. ago, never had a upper on it yet.  Can I buy a 10" upper and use it on the lower (pistol buffer tube still in tact), while the form 1 is being processed?

Yes

2. If after receiving the form 1 and stamp back from BATFE, can I use any length/caliber upper on the newly registered sbr lower?
Yes. If you get rid of the original configuration, it's a good idea to notify them in writing, but you ARE free to use whatever calibers/lengths you want.


3. After it's registered, can i convert back and forth from a sbr to a rifle (16" and up) upper legally?

Yes. In fact there's an opinion letter from the ATF stating that if you put a 16" or + upper on an SBR lower, you can take it to a non-NFA-friendly state.... without ATF approval.

Any and all help would be appreciated, i've tried reading thru the sbr section and it gets a little confusing.  I just want all the correct facts first before doing anything.  Don't want the MIB showing up at my front door bcause I did something wrong...  lol

I just read about people having cycling problems with 10.5" uppers, how would this be remedied.  I was planning on a 10.5" built on a Rock receiver and BCG with a YHM barrel.  

Most cycling problems on SBR's are addressed by either: 1. Trying different ammo. 2: Changing out the buffer for a heavier/lighter one. 3: Changing out the buffer spring for a heavier one. 4: Last option is to open up the gas port if you are under-gassed.

thanks