quote:

When a gunsmith does a trigger job on a Mauser, he will likely try to reduce three things and then test:
1) Trigger force
a) The rear hump on the trigger is reduced to make a different camming angle of the trigger on the receiver.
b) The spring can be exchanged for a lower force or coils may be clipped from the original
c) The surfaces may be polished:
.1) Cocking piece on bolt assembly and the sear mating surfaces. These must maintain their flat shapes to the mating surfaces. This is an advanced task. If the corner gets rounded, the trigger will not break clean, so the surfaces are not polished with wire wheel, but best in a stoning jig. These surfaces are probably already smooth enough.
.2) Hump on trigger to underside of receiver mating surfaces
.3) The two pins in the trigger assembly may be polished or the holes may be reamed and lapped and the pins replaced with ground and polished pins of a larger size.
d) The angle of the sear and cocking piece engagement can be reduced in some guns, but I have never seen it done in to a Mauser. This is not recommended unless you really know what you are doing. The parts can be easily wrecked and it could cause accidental discharge.
e) The mating surfaces can be lubricated.

2) Take up, this is how far the trigger must be pulled before firing pin release. This is done with a sear engagement adjustment. This adjustment must be enough for safety margin. A good safety test for this is to cock an unloaded gun, and slam the but on the floor and see if the gun fires. If not, add a little more engagement for safety, and set the lock nut.

3) Over travel, this is how far the trigger can be pulled after the gun has fired. Reducing this distance increases accuracy, but if it to short, the gun will not fire.

4) Test for safety. The trigger job may seem to work fine on the bench, but the assembled rifle with screws tightened and the stock in the way may change things. The above but slamming is good, but also cocking the gun repeatedly with the trigger slightly pulled is another test for safety margin. If the gun sometimes does not cock, then more spring force or sear engagement or cutting wood out of the wary, or something is needed.



I should probably quantify what I earlier said about spring wimpyness. The stock Mauser trigger spring has a relaxed length of ~ .74" and is compressed to ~.47" when the gun fires. At that point the spring force is about 15 pounds. That force is translated through the geometry of the trigger to ~ 1 pound of trigger force [ due to trigger spring alone]. The spring has a coil dia of .25" and a wire diameter of .040" giving a spring index of 6.25 [a fairly stiff spring].

I have been substituting springs with relaxed length of .61", a coil dia of .235" and a wire dia of .020" for a spring index of 11.75 [a fairly wimpy spring]. These springs at the point of firing have a force of ~ 1 pound. This translates to ~ one once ounce at the trigger [due to trigger spring alone], less with the rear hump of the trigger ground off. This is not a good choice for military or hunting, but works well for me for targets and varmint hunting.