The second battery is on 2F and in an effort to get up there, you have to take out the stone on 1F on the appropriate facet in the elevator. Scorpion mags procured from PSA do not enable final round bolt keep open up. PSA mag that came with AK-V https://ammunitionsdistros.com/product/american-tactical-milsport-300-blackout-optics-ready-semi-automatic-rifle-with-mlok-rail/