That's a great question... the answer is maybe.
So what can you do to avoid 922(r)?
You would need to consider the following criteria.
CRITERIA ELEMENTS 1 - 5
1. Does the weapon have a military configuration?
a. ability to accept a detachable magazine?
b. folding/telescoping stock?
c. pistol grip?
d. ability to accept bayonet?
e. flash suppressor?
g. grenade launcher?
h. night sights?
2. Is the weapon a semiautomatic version of a machinegun?
3. Is the rifle chambered to accept a cartridge case having
a length of 2.25 inches or less?
4. How has the rifle been advertised/marketed?
5. Technical Writers Descriptions:
The ATF feels that the VALMET Hunter is a sporting rifle,
but the M76 Counter Sniper is not. I would say that a PSL
lacking provisions for a flash suppressor,night sights,grenade launcher,
bi-pod,bayonet,folding stock,or magazines greater than 10 rounds
and a thumbhole stock meets the definition of a sporting rifle.
You would have to write the ATF for a firm decision, as it seems
that anything with a pistol grip is somehow non-sporting.