Picked up an SGL-21 and took it to the range to sight it in. I noticed all the rounds were hitting 10 o’clock. Upon closer examination I saw a slight cant in the FSB. The 25m test target also shows all the rounds hitting left of the black circle.
My options are to either fix the canted FSB or just get an Ultimak/T-1 setup, run the optic and be done with it.
Suggestions?
Have you adjusted the windage of the front sight?
If it adjusts to be correct to POI and isn’t crazy off to one side - leave it and move on.
Otherwise - send it back to Arsenal to get fixed.
Then get optics.
Yup, you just need a tool like this one. Not a huge deal to fix. 
What he said…
I’d contact Arsenal and get it sent back for service. I sent my SLR-106 back for feed ramp issues through the place of purchase, and it it didn’t cost me anything to have shipped back either. Since it’s new, the FSB issue should be free to fix also. It was fairly painless, you’re just without a rifle for a while.
Even if you could still get a decent zero, that would piss me off. Send it back.
I would send it back too. That is obviously a miss by Arsenal & they need to at least be aware of it so that they can fix their QA/QC folks.
Hitting 10 0’clock where ? in the black ? just outside the black ? the test target shows rounds hitting how far left of the black ? this could be corrected with a simple windage adjustment .
Two rounds were about an inch and a quater to the left of the black, the other round hit 11 o’clock and was right on the edge. I can’t believe they stamped the target and said it was GTG after seeing the results of the test firing.