THE ROYAL ARTILLERY INSTITUTION. 
315 
3rd. Firing- Position.— -When the block is in the firing position, should the 
striker strike the cap too high, an amount not exceeding ’01 in. taken off the bearing 
surface of the lever horns at B will be sufficient to rectify the error. 
4th. Should the striker strike the cap too low , the horns of the lever may be 
drawn out between the lines indicated at D not to exceed *01 in., care being taken 
not to spread the horns or set them out of position at C. 
Extractor. —When the block is at the loading position the point A should be 
just free from the underside of the block. 
When the block is depressed to the lowest position it should bear on point B , 
holding the extractor firm; but should the lever at B touch the guard so as to pre¬ 
vent the block doing this, the guard may be filed to allow the lever to be clear. 
The point B should be on the trigger when the extractor is at its lowest position ; 
if it will not bed down, the fault must be looked for on the head of the trigger 
spring screw; if this stands too high, it should be filed flat. 
Trigger. —In replacing a trigger, care must be taken not to shorten the nose in 
adjusting the pull off, as this affects the loading 'position of the block. The trigger 
pin should be a close fit, as the correctness of the “pull-off” chiefly depends upon it. 
Trigger Spring. —In replacing a trigger spring, care must be taken that the 
head of the screw beds well down on the spring, and that the point does not bear 
on the guard swivel screw. 
Tumbler Rest. —In replacing a tumbler rest care must be taken not to file 
away the bent in adjusting the pull off, as this affects the loading position of the 
block ; the front edge of bent should be slightly rounded to free it from burrs. 
Tumbler. —In replacing a tumbler, it should pass firmly on to, but not be 
driven hard upon, the squares of the axis pin ; it should also work freely between 
the horns of the lever. 
Indicator. —Remarks same as upon tumbler. 
Lever. —In replacing a lever, the bearings at point A should be free when the 
lever is depressed; otherwise it prevents the block from having its fullfall. 
The end of the lever must be set to drop freely into the lever catch block; care 
must also be taken that the lever beds on its seat at the under side of socket end of 
body. 
The levers issued with the spare parts are for short butts—they will require 
setting for long butts—a slight blow with a mallet is all that is required to make 
them drop freely into the lever catch block; the levers for short butts are issued in 
preference to levers for long butts, as the adjustment required by the former to fit 
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