Try this version on for size. No FF armor, and no Artemis IV, but 1 ton of the saved weight goes to another ton of ammo and the other to making up the difference in armor protection.
Note that FF armor is 20k/ton and Artemis LRM Ammo is 60k/ton.
Catapult CPLT-C1 Merc
Mass: 65 tons
Tech Base: Inner Sphere
Chassis Config: Biped
Rules Level: Advanced Rules
Era: Succession Wars
Tech Rating/Era Availability: E/X-F-E
Production Year: 3025
Cost: 14,103,925 C-Bills
Battle Value: 1,742
Chassis: Unknown Standard
Power Plant: Unknown 325 Fusion XL Engine
Walking Speed: 54.0 km/h
Maximum Speed: 86.4 km/h
Jump Jets: Unknown
Jump Capacity: 150 meters
Armor: Unknown Standard Armor w/ CASE
Armament:
2 LRM-15s
4 Medium Lasers
Manufacturer: Unknown
Primary Factory: Unknown
Communications System: Unknown
Targeting and Tracking System: Unknown
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Equipment Type Rating Mass
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Internal Structure: Standard 104 points 6.50
Engine: XL Fusion Engine 325 12.00
Walking MP: 5
Running MP: 8
Jumping MP: 5 Standard
Jump Jet Locations: 1 CT, 2 LT, 2 RT 5.00
Heat Sinks: Double Heat Sink 10(20) 0.00
Gyro: Standard 4.00
Cockpit: Standard 3.00
Actuators: L: SH+UA R: SH+UA
Armor: Standard Armor AV - 200 12.50
CASE Locations: 1 LT, 1 RT 1.00
Internal Armor
Structure Factor
Head 3 9
Center Torso 21 28
Center Torso (rear) 11
L/R Torso 15 22
L/R Torso (rear) 8
L/R Arm 10 20
L/R Leg 15 26
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Equipment Location Heat Critical Mass
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LRM-15 RA 5 3 7.00
LRM-15 LA 5 3 7.00
Medium Laser RT 3 1 1.00
Medium Laser LT 3 1 1.00
Medium Laser CT 3 1 1.00
Medium Laser HD 3 1 1.00
@LRM-15 (8 ) RT - 1 1.00
@LRM-15 (16) LT - 2 2.00
Free Critical Slots: 25
BattleForce Statistics
MV S (+0) M (+2) L (+4) E (+6) Wt. Ov Armor: 7 Points: 17
5j 2 2 0 0 3 0 Structure: 3
Special Abilities: CASE, SRCH, ES, SEAL, SOA, LRM 1/2/2, IF 2