GUN SIGHT MARK 14 Gunner's Operating Bulletin No. 2 United States Fleet Headquarters of the Commander in Chief

GUN SIGHT, MARK 14

MODS. 6, 7, & 8

Gunner's Operating Bulletin No. 2

UNITED STATES FLEET

HEADQUARTERS OF THE COMMANDER IN CHIEF

	1	Turn the Control Switch on the Power Unit ON.
	2	While you're there, check the air pressure gage. There are two types of dials: one has red and green sectors on it; the other is numbered. On the first kind, the pointer should be in the green area. On the second type it should be between 6 and 8.
		If the pressure needs adjusting, REPORT THE FACT IMMEDIATELY TO THE FIRECONTROLMAN WHO MAINTAINS YOUR GUN SIGHT.

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3	Check to be sure that the hose connections are tight. The hoses must be free from kinks for all positions of the gun or director.
4	Test the reticle bulb and reticle dimmer control. The reticle dimmer knob controls the brightness of the reticle bulb. This bulb has two filaments, one of which is for emergency. Turning the knob to the right lights one filament, turning it to the left lights the other. If either of the filaments has burned out, the bulb should be replaced as soon as possible.
	To make the bulb last longer, always be sure that the dimmer knob is in the "OFF" position when your Sight is not in use.

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5

Let the Sight warm up. The warm-up time is 1/2 hour (30 minutes). To get the best operation from your Sight, be certain that it has the full warm-up period. This means, of course, that when your Sight is in a combat zone, you will let your Sight run continuously. In an emergency (and then only!) the Sight can be used after a 10-minute warm-up, but remember—its accuracy will be reduced considerably.

When you are warming up your Sight, be sure the gun is in its Horizontal Locked Position. If it is necessary to elevate the gun at all during this time, don't leave it up for more than 2 minutes. This precaution assures that the damping fluid is in the correct position.

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6	CHECK THE RETICLE ACTION AFTER THE SIGHT HAS WARMED UP.
	Set the range to maximum: Mod. 6 . . . . . 2000 yards Mod. 7 . . . . . 2800 yards Mod. 8 . . . . . 3200 yards
	Turn on the reticle dimmer control: when the gun is at rest, the reticle should appear near the center of the window.

Slew the gun or director to the right: as you move it, the reticle should move to the left and lag behind the gun barrel.

Stop moving: the reticle should move in toward its first position: it should move freely—not too slow, not too fast and it should slow up as it gets back toward the center of the window.

Now slew to the left, and watch the reticle: slew up then down.

If reticle action is not normal; report it to the firecontrolman who maintains your Sight.

 

7	Cock the Gun: To prevent injury to the gyro units when you cock the gun, be SURE that the range knob is set to maximum.

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Gun at rest Reticle centered
Gun to right Reticle to left
Gun to right Reticle to right
Gun up Reticle down
Gun down Reticle up

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ALL READY TO GO ?

Check these points:

Ready Check List
ARE YOU SURE THAT Power unit pressure is O.K.?
House connections are tight?
Reticle bulb and dimmer controls are O.K.?
Sigh has had half an hour to warm up?
Reticle action is O.K.?

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"O.K. Stand by for Action!"
1
Set your Range Knob at 400 yards. This limits the movement of the reticle and makes it easier for the gunner to pick up targets.
2
Set Spot Knobs at zero. Line up white zero mark on each knob with index mark on Sight case.
3
Adjust reticle brightness to fit weather conditions. Don't have the reticle so bright it blinds you. If necessary, swing light filter into place. It's con- trolled by the knob on left hand side of the Sight.

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These instructions apply either to the Gunner on a 20 mm gun or to the Pointer on a Gun Director Mark 51

How to Pick Up Targets

1		First look over or around your Sight to locate the target.
2		With the Range Knob at 400 yards, slew the gun and frame the target with the reticle.
3		Sing out "ON TARGET" so the Range Setter can set in the correct range for opening fire. IF YOU'RE WORK- ING WITHOUT A RANGE SET- TER, to save time, leave the range knob at 800 or 1200 yards. Slew the reticle past the target, "over-shooting" him, reverse your direction, and then start tracking. This will help to "settle the reticle much more quickly.

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How to Frame
and Track a Target

Remember you're working with a LEAD-COMPUTING GUN SIGHT. This means that when you have your target framed in the reticle and are tracking smoothly, your gun is being aimed ahead of the target AUTOMATICALLY. If you lead the target with the reticle, you will defeat the purpose of the computing mechanism—so

LET YOUR SIGHT WORK FOR YOU!

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For the GUNNER (Continued)

How to Track Smoothly

Once the target has been framed, your most important and your toughest job is TRACKING SMOOTHLY. Smooth, even tracking will give you more hits than any other single factor. YOU CAN DO IT IF YOU PRACTICE.

Move the gun with smooth, steady motion and avoid jerky or uneven action. If you let the target get out of the reticle and then jerk the gun to get it back in again, you will produce an error in the lead which will not be corrected until after an applicable interval of smooth tracking.

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To help adapt yourself to the roll and pitch of the ship PRACTICE TRACKING WHEN EVER POSSIBLE. Use the horizon, BIRDS, and the training scale for the calibration and training fixture—it doesn't matter much what you practice with so long as you DO PRACTICE until that steady, smooth tracking rate is as natural to you as breathing.

Before opening fire, track the target long enough to allow your Sight to establish the correct lead. Normally, a second or two is sufficient.

 

 

TRACK LIKE THIS

 

NOT THIS

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WHEN TO OPEN FIRE

Very often, on incoming targets, the Gunner or the Director Pointer can estimate the range and tell when to open fire by noting the size of the target relative to the inner circle of the reticle

NOTE: The inner circle of the reticle on the Mod. 6 Sights used with the 20 mm. gun is 25 mils in diameter. On the Mods. 7 and 8 Sights with the Mk 51 Director it is 15 mils.

20 MM. GUN

MK 51 DIRECTOR

Open Fire at 1500 yds. when target looks like this:

Open Fire at 3000 yds. when target looks like this:

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ANY gunner can learn to track in practice It takes a GOOD ONE to track smoothly AFTER THE GUNS LET GO.

When you pull the trigger, your troubles begin. On the 20 mm, gun you will have SHAKE, NOISE, and SMOKE—and lots of it. If you are a Director Pointer there will be BLAST and SMOKE—and plenty of that, too. YOU MUST KEEP TRACKING SMOOTHLY ANYWAY—

Follow through with the motion you were using—glue your eye to the target—give it a fraction of a second and if you are goo you'll

 

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For the GUNNER (Continued)

spot it through the smoke right in the center of the reticle.

When you are new on a Sight don't try to fire in a steady stream. The smoke, the shake and the blast will get you. You'll kid yourself you were on and shoot all over the sky. Check fire after each short burst, just long enough to see that you are on. As you grow more and more used to firing, increase the length of each burst until you are firing a steady stream into the target.

If the smoke and blast from near-by guns gets too much for you under certain conditions, take a lead with your Sight, cock your head 'way over to the left and fire tracer control. Get back to your Sight as soon as you can. Your are losing hits—and lots of them.

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GUNNER'S   Reminders

1.	Keep target framed in the reticle.	6.	Don't stand too close to the Sight.
2.	Track smoothly.	7.	Don't have height of trunnion changed when firing—for incoming targets have the trunnion as high as you can stand comfortably, and walk in toward the base of the mount to elevate the gun. For passing targets, have the trunnion lower than for incoming targets and shift your weight and footing carefully to get smooth movement.
3.	Fire in bursts at first, then increase to a steady stream. Check fire momentarily if the target gets out of the inner circle—you won't be getting hits and you are just making it difficult to get back on.	8.	DO practice picking up targets and tracking smoothly whenever you can.
4.	Don't keep your head in one position. Move your head around to keep the reticle in view.
5.	Don't concentrate on the reticle—concentrate on the target in the reticle.

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WHEN the Gunner has established a smooth and accurate tracking rate, this matter of scoring hits rests squarely on you, the Range Setter. If both of you do your jobs accurately and carefully, you will form a highly effective team. While the Gunner takes care of

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tracking and firing, you will set the right range on the Gun Sight and make spot corrections if they are necessary.

3 THINGS

ALL RANGE SETTERS

SHOULD REMEMBER:

1	Each time you make a large change in range or move the spot knobs, you move the reticle away from the target. This will throw the gunner off for a fee seconds, until he can re-frame the target.
2	To avoid throwing the gunner off more than necessary, make all range changes as smoothly as possible, but don't freeze on the range knob.
3	Don't make spot corrections during the firing.

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The Range Knob

WE'VE TOLD THE GUNNER HOW IMPORTANT HIS SMOOTH TRACKING IS—if he tracks smoothly, his gun is moved ahead to take care of the correct lead or "aim-off". This, of course is true only when the range you set is close to the target. When you change range setting you change the amount of lead: use the Range Knob carefully. The knob has "detent" positions every 400 yards: you should train yourself so that you can tell by feel what range is set on the Sight.

	The Spot Knobs
	The purpose of the Spot Knobs is to correct for definite errors in the line of fire (caused by wind, drift, or boresight errors). The knob marked "DEFL" corrects in train: The "ELEV" knob corrects for elevation errors. Both knobs have detents in 5 mil steps, with a total correction of 25 mils on either side of the zero pointer. Moving the knobs "Right" or "Up" moves the tracers right or up.

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GUNNER SETTING ON
THE 20 MM GUN

BECAUSE of the speed of the target and the range limitation of the gun, the effective firing periods of the 20 mm is limited to a few seconds. TO GET IN THE MOST LICKS before its too late—

FOR INCOMING TARGETS
(Those Coming in to Get You)

Set the Range Knob at 800 or 1200 yards AND LEAVE IT THERE. The Gunner should open fire before the target gets in to the range you have set on the sight.

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For the RANGE SETTER (Continued)

 

FOR PASSING TARGETS
(Those Going After Somebody Else)

Set the Range Knob to the estimated range of the target. The gunner should open fire as soon as he has established a smooth tracking rate.

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You should watch the tracers, and if there are large, obvious errors in lead, make range corrections like this

	Missing BEHIND, Increase your range.
	Passing through, Range O. K.
	Missing AHEAD, Decrease your range.

 

DON'T
USE THE SPOT KNOBS

There should be no need for spot corrections except for an obvious error in boresighting. If you try to make spot corrections, you will move the reticle and throw the gunner off his target.

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RANGE SETTING ON THE
GUN DIRECTOR MARK 51

The guns controlled by the Mark 51 have longer effective ranges, so you will have more time to make range corrections during the run.

 

FOR INCOMING TARGETS

When the Director Pointer sings out "ON TARGET!", estimate the actual range to the target, and set a shorter range on the Range Knob. . . . Like THIS—

You're on a Zero at 3000 yards. Set the sight range at 2400.

Your Director Pointer should start firing immediately. He shouldn't wait for the target to come in to 2400 yards.

Watch the tracers! Because the range set on the Sight is too short, it is computing too little lead, so the tracers are falling below and behind him. They won't for long, because he' closing in to that range FAST.

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As he closes range, the tracers will "walk up"on him because he is reaching the range for which the Sight is computing the correct lead.

If he gets through your fire and continues to close, the tracers will walk out past him and appear above and ahead of him.

The reason for this is that the target is now inside 2400 yards. The range set on the Sight is not too great, so the Sight is computing too much lead.

Don't wait 'till you're shooting 'way ahead of him. Step down your range NOW, by 800 yards, SMOOTHLY.

With the range at 1600 your tracers will "walk up" on the target again, until they are passing through him and you are getting hits.

Be sure that the tracers pas through and above the target before decreasing the range setting.

 

 

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For the RANGE SETTER (Continued)

If you see tracers passing either side of the target and you know the Director Pointer has been tracking accurately, use the Deflection Spot Knob. (Small errors like this can be caused by wind, drift or boresighting.)

FOR PASSING TARGETS

On shots like these YOUR skill means much, because any errors in range setting produce large errors in lead. Set the Range Knob to what you estimate the target range to be. The Pointer will track immediately and open fire. YOU, as Range Setter, watch the tracers

General Rules: Increase range to increase lead.

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FOR OUTGOING TARGETS

Set the range knob to greater range to the target. The tracers will appear to pass ahead, and above the target. As he gets into the range set on the Sight, he will have to pass through the tracers, and if he gets beyond that range, the tracers will appear to pass below and behind him. Now increase the range smoothly in steps of 800 yards until the tracers are ahead of him again. DON'T LET HIM GET AWAY.

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Keep your eyes open—for
targets and safety

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  HOW TO SECURE YOUR

GUN SIGHT MARK 14

You'll want to be certain that it's property protected so that it can work as well for you the NEXT time you use it—so be sure you know what to do when the word comes to SECURE—

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HOW TO SECURE YOUR

1.	Set the range knob to 400 yards. Do not change range when the Sight is cold.
2.	Secure your Sight in the horizontal locked position.
3.	Turn the Control Switch OFF.

Be around when the firecontrolman makes the required periodical tests, and know that your Sight is right!

KNOW YOUR SIGH

PROTECT YOUR SIGHT

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