To read black shell..you should set the eye up for the paint..the manual will tell you how to do it.
You can up the eye off settings...
Go into TIMG via the button in the grip.
Scroll down to CDEL...set this at 3......
Then scroll to COFF....set this at 20...or less if you like, test for correct cycling...
Then scroll to CON....this will be set at about 60 something...
You can reduce this number as much as you dare, until it will no longer cycle a ball..then up it one by one till it consistently cycles and shoots a ball....mine is set at 40.
To work out maximum ROF in eye off...1000/CDEL+ CON+COFF
In this case CON at 40 COFF 20 CDEL 3 ...1000/63=15.87 BPS.
Naturally, in EYE n mode you can shoot as fast as you can feed it!
If you have a Nexus Ram and QEV's fitted....make sure CDEL is set to 6...