each class is unique in what weapons they specialize in.
The weapons are close range, med range, long range, explosives and special.
Mark VI
CR=5
MR=5
LR=5
EX=3
SP=5
CQB (Close Quarters Battle)
CR=7
MR=5
LR=5
EX=3
SP=3
ODST
CR=5
MR=7
LR=3
EX=3
SP=5
Scout
CR=5
MR=3
LR=7
EX=5
SP=3
EOD (Explosives Ordnance Disposal)
CR=3
MR=5
LR=3
EX=7
SP=5
Recon
CR=3
MR=3
LR=5
EX=5
SP=7
The Number system is where each class starts with experience in that weapon class. more points means more weapon attachments and higher points means better attachments.