Technical information

Practical A.E.G Upgrade 2006

When inserting the “next gear”, always make sure that it aligns correctly with

the previous one. Keep in mind that:

 the teeth of the piston must be correctly aligned with the teeth of the sector

gear, or the piston teeth will be unevenly stripped.

 there should almost be no gap between the sector gear and the spur gear,

or the teeth of the sector gear will break within 600 rounds at the time the

spring is compressed.

 the anti-reversal latch must be properly positioned relative to the bevel gear,

or the latch will worn out prematurely.

One good approach is to reference the way shimming has been originally done.

The logic is simple – we need to re-shim because the stock bushing has a size

(thickness in particular) slightly different from that of a metal bushing. Since the

metal bushings share one same size between themselves (as long as they are

name branded bushings from the same pack), chance is that you simply need to

do minor adjustment at each location to compensate for the difference in

thickness between the stock bushing and the metal one. Do note that this

approach assumes that you do not replace the gears at the same time. Gears

from different manufacturers do vary slightly in sizes and dimensions.

Go through several rounds of trial fire until there is almost no gap between the

gears and at the same time they can spin smoothly without much resistance. *

When we say almost, we mean the gap should be minimized but NOT

completely eliminated. If the two gears are touching each other, you will run into

problem too (due to excessive friction).

Spur gear breakage:

If your spur gear breaks, it is NOT necessarily due to poor shimming. If several

teeth were broken together on the spur gear, chance is that the spring that you