*** Disclaimer*** I am NOT a gunsmith, just a shooter and hunter. What follows reflects my experience only. I assume no responsibility for the alterations you may or may not choose to make to your own rifle!
Now that that's out of the way...
A few days ago I bought a new Thompson/Center Venture
rifle in 7mm Mag. A friend had bought one a couple of months ago, and
the rifle's out-of-the-box accuracy was on par with the Savage rifles I
have loved and shot for the past decade. My only complaint with his
rifle (and mine) was the triggers. They were stiff and a little creepy.
I dug around on the Internet for an afternoon, and couldn't find any
solid advice about adjusting the triggers, and after-market triggers are
non-existent. The only advice available was to dismantle the trigger,
cut a loop out of the trigger spring, and re-assemble it. In the piece
that follows, I try to go beyond that simple fix, and further modify the
trigger to eliminate creep.
Begin by removing the barreled action from the stock. You'll have something that looks like this:
Drive out the two pins holding the trigger group to the action. They're
labeled "trigger group removal pin" and "trigger group removal pin 2"
in the photo. I have also labeled the over-travel screw and the creep
screw for reference. We'll get to those at the end.
Now you have the trigger group:
Use a pick or X-acto knife to pick away the epoxy that seals these screws:
Remove the 3 C-clips that hold in the safety lever assembly, the
sideplate locking pin, and the trigger pivot pin. Follow by removing
the two sideplate locking screws:
Set aside the sideplate to expose the internals:
Remove the spring between the trigger and the sear (the trigger spring).
Cut out one loop of the spring. Remember, you can't put the spring
back together, so too little is better than cutting away too much and
ruining the spring. Please note that where the spring contacts the
trigger itself, there is a small guide plug. After cutting the spring,
put that plug in the cut end, and re-install the spring upside down, so
that the cut end and the plug ride on the trigger, not the sear.
Re-assemble the trigger group. Re-install it into the rifle. Use the
Allen head screw labeled below to make the final adjustment to your
trigger pull. It can be accessed with the trigger group mounted to the
action by slipping the Allen wrench into the back of the action with the
With the epoxy cleared away from earlier, you have access to the
adjustment screws. If you look at both adjustment screws, they are a
threaded shaft with a locking nut. If you pick away the epoxy at the
outside end of the shaft, you'll discover that it is really an Allen
head set screw.
To adjust either screw, loosen the nut, then use an Allen wrench to turn
the adjustment screw. When you have the screw adjusted as you like,
tighten the lock nut back, and add a drop of nail polish or Locktite
Temp to prevent the screw from loosening later.
The screw at the front of the group controls over-travel (how far past
breaking the trigger will continue moving before it is stopped).
The over-travel on mine was fine, so I didn't adjust this feature.
The screw at the rear and bottom of the group controls creep (how far
the trigger moves before it breaks). Mine was creepy from the factory,
so I adjusted this one. I dialed the creep completely out by cocking
the action, then tightening the screw until the trigger broke (making
the gun fire). I then backed the screw out just a little and tightened
the locking nut.
If anything is less than satisfactory, re-adjust until you have the trigger pull, creep, and over-travel to your liking.
After adjusting, I changed my Venture's trigger pull from a stiff 7 lbs to 2.5 pounds, and eliminated the distracting creep altogether.
Now My friend whose Venture hooked me in the beginning wants me to do his.