table class="prettytable"> Designation 6"/47 (15.2 cm) Mark 17 Ship Class Used On Erie Class Date Of Design 1933 Date In Service 1938 Gun Weight 5.24 tons (5.32 mt) Gun Length oa 289.0 in (7.341 m) Bore Length 282.3 in (7.169 m) Rifling Length about 238.3 in (6.053 m) Grooves N/A Lands N/A Twist Uniform RH 1 in 30 Chamber Volume 1,478 in³ (24.22 dm³) Rate Of Fire 5 - 8 rounds per minute

Type	Bag
Projectile Types and Weights 1	Common Mark 28 Mods 1 and 2: 105 lbs. (47.6 kg) Illum Mark 22 Mod 1: 95.40 lbs. (43.3 kg) Illum Mark 23 Mods 1 and 2: 96.0 lbs. (43.5 kg)
Bursting Charge	Common Mark 28 Mods 1 and 2: 5.72 lbs. (2.6 kg) Explosive D
Projectile Length	27 in (68.6 cm)
Propellant Charge 2	34.5 lbs. (15.7 kg) NC 34.0 lbs. (15.4 kg) SPD or SPDN
Muzzle Velocity	Common 2,800 fps (853 mps)
Working Pressure	18.5 tons/in2 (2,910 kg/cm2)
Approximate Barrel Life	750 - 1,050 rounds
Ammunition stowage per gun	N/A

• ^This gun used the same projectiles as the Mark 16.
• ^Propellant was in a single bag.
• Bourrelet diameter was 5.985 inches (15.2 cm).

Range with 105 lbs. (47.6 kg) Common Shell

Elevation	Range
20 degrees	19,800 yards (18,100 m)

Designation	Single Pedestal Mounts     Erie (4): Mark 18
Weight	15.4 tons (15.65 mt)
Elevation	-10 / +20 degrees
Elevation Rate 1a	N/A
Train	about +150 / -150 degrees
Train Rate 1a	N/A
Gun recoil	24 in (61 cm)
Loading Angle	N/A

• ^1.11.2Used 3.5 hp motors for elevation and training.