Yes that's possible but it's not the correct way.
I don't know how but I've seen 2-3 guns with missing pcs screws!
I don't know if you can find a pcs bolt on a retailer shop, the pcs is discontinued for some years.
If you want another bolt you can get the G&G Power Bolt, it doesn't have a PCS but it certainly produces more fps than the stock Tanaka bolts.
Wolf