TexasMac's Web Site
By Wayne McLerran
Updated 10/15/18

Due to the factory trigger pull-weight the most common modification
to the Miroku manufactured Browning or Winchester 1885 is to lighten
the trigger pull. The limited adjustment pull-weight is fine for hunting
but even at the lightest setting it’s considered too heavy for
competitive shooting.  In my book on the rifles I included a long chapter
on lightening the trigger pull.  In it I note that
after-market set triggers
are not available for the rifles and discuss the four common methods to
reduce the trigger pull-weight, but only recommend two for safety
reasons.  A simple and safe method is to replace the trigger spring with
a lighter one but most competitors find that the resulting weight
reduction is not adequate.  The preferred solution is to have a trained
professional gunsmith work on the trigger sear.

The trigger spring is located under the rear of the trigger, surrounding
the trigger adjustment screw.  The trigger sear is pinned to one end of
the trigger.  In order to access either one the stock must be removed
and the trigger pin pushed out, releasing the trigger/sear.  As detailed
below, the process is relatively simple.  Take your time and take note
of the caution comment on removing the stock bolt.

Removing the Stock:

In the order listed, remove the butt plate screws, butt plate, the stock
bolt, and receiver tang screw.  Removing the stock bolt requires a
common blade (flat-bladed) screwdriver with a shaft approximately
8.5” long, and note the caution comment below.  The receiver tang
screw should be removed after removal of the stock bolt.  On some
rifles, lateral pressure from the stock bolt will lock the tang screw in
place, making it quite hard to remove, increasing the risk of twisting
off the screw or damaging the screw head.

The stock can now be removed.  Due to a tight fit the stock may
require some gentle (very gentle) “wiggling” to release it from the
receiver.  Be very careful so as not to split the stock on either side of
the tang slot.

Caution - when removing the stock bolt using a standard wide flat-
blade screwdriver, the blade tip can easily and unknowingly become
wedged between the stock bolt head and the stock, cracking the stock
when the screwdriver is turned.
Tip - to ensure the screwdriver tip is centered, slip a thick piece of
rubber tubing over the shank an inch or two above the tip, or wrap the
shank with tape until the diameter is slightly smaller than the stock-
bolt hole.

Removing the Trigger/Sear:

With the rifle upside down (bottom of the action facing upward) and
the stock removed, push out the trigger pin.  When the action is held in
the normal shooting orientation, the trigger pin is located just behind
the receiver in the lower portion of the trigger housing assembly.  
Using a brass punch or similar tool, it should be easy to push out from
either direction, allowing removal of only the trigger assembly and
trigger spring.  The trigger assembly consists of the trigger, trigger sear
and trigger sear pin.

By the way, with the trigger and trigger spring removed, take the
opportunity to check if the trigger pull adjustment screw is free to
adjust.  Once the trigger pull is adjusted by the factory, shellac or
some type of varnish-type adhesive is applied to the screw to minimize
adjustments.  If you’re not the 1st owner of the rifle, the prior owner
may have discovered that once the shellac is removed the screw is easy
to adjust.  If yours is hard to adjust, using an appropriate fitting
screwdriver, complete remove the screw and remove any shellac.  Also
check the recessed and threaded hole in the bottom of the trigger
assembly, which is where you’ll likely find the remaining shellac.  In
most circumstances the adhesive comes out with the screw and can be
easily removed, but an 8-32 tap may be necessary to get it all.  Once
all the shellac is removed, reinstall the adjustment screw.  Screw it all
the way in than back it out about ½ turn prior to reinstalling the
trigger spring and trigger.

Installing the trigger/trigger sear and trigger pin:

1.        With the rifle upside down (bottom of the action facing upward)
install the trigger spring by sliding it over the trigger pull adjustment
Note: Prior to installing the trigger assembly, ensure that one end of
the hammer sear spring is properly resting in the groove of the rear
mainspring pin/rocker.  The end of the spring and the mainspring pin/
rocker should be visible by shining a flashlight into the trigger housing.  
When the trigger is removed, tension is removed from the hammer
sear.  If the rifle is jarred or shaken, the hammer sear spring can move
out of the groove.  If the hammer sear spring is not seated correctly it
can cause the hammer sear to rotate back too soon, resulting in the
hammer catching in the half-cock position when attempting to fire the
rifle.  Once the trigger is installed, spring tension will hold the end of
the hammer sear spring in the groove.
2.        Insert the assembled trigger assembly consisting of the trigger,
trigger sear and trigger pin.
3.        Align the hole in the trigger assembly with the hole in the
trigger housing and push in the trigger pin.  It should slide in easily if
the trigger and trigger housing are aligned, but may need a light tap
with a hammer.  It cannot fall out once the stock is installed.
4.        Install the stock using the reverse of the procedures outlined in
the disassembly above.  Be very careful so as not to split the stock on
either side of the tang slot.  Install and tighten the receiver tang screw
first.  Heed the previous warnings to ensure the stock is not cracked
with the tip of the screwdriver.  And do not over tighten the stock
bolt, which will increase the risk of cracking the stock.

Wishing you great shooting,