NOTE: before you go any further, these modifications take a very good knowledge of the inner workings of the Typhoon to execute and make work well. If you can't take your Typhoon or Stroker apart and put it back together without instructions or help I do not recommend you try any of this. I take no responsibility for what results from your trying any of this, and I wouldn't blame Glenn Palmer for telling you off for screwing your gun up for trying this either (he's already told ME off for posting this once before). In other words, don't do any of this unless you know you can fix your own gun yourself.
The Typhoon/Stroker series of Sheridan-based Palmers semi-autos are exceptional paintguns. With a high degree of reliability, consistency, and accuracy as good as anything else out there, I've always felt that it offered an excellent, relatively inexpensive option to people looking for closed-bolt performance without having to take a class in keeping an Autococker maintenance. The only complaint I consistently hear (and feel myself) about the gun is that it has a very heavy, numb, sometimes even gummy feeling trigger pull, lacking the quick snappy feel of an Automag or well tuned Autococker that allows rates of fire at and above 4-5 rounds per second.
This does not have to be the case.
With a few simple modifications to the trigger assembly (that are, best of all, easily undone if they don't work well on your gun) you can dramatically reduce the pull effort of your Typhoon or Stroker. Even if you don't plan on firing over 4-5 rounds per second I've found that raising the gun's limit makes it easier to fire it where you like to. For example, I can rarely coax my finger to squeeze more than 4-5 rounds per second out of any gun, but since working on my Typhoon's trigger, I find it easier to fire at that rate with less fatigue and gun movement.
First, though, I'd like to describe the problem.
When you release the trigger, 3 things must occur:
Now let's look at the stock trigger configuration:
- The sear must be pushed back up to catch the hammer in the cocked position
- The trigger must be pushed forward to be ready to fire again (this is linked to the sear, so if 1 occurs, 2 will naturally follow)
- The piston of the 4-way valve must be pushed back up to the point where it directs the ram to move the bolt back into the closed position. It is this third action that requires, by far, the most force to do.
There are two springs acting to return the trigger/sear/4-way assembly to the firing position. One is a standard coil spring in the frame oriented horizontally, pushing the trigger forward directly through the timing rod. This spring also delivers return force to the 4-way valve indirectly through the rocker arm which converts the horizontal trigger motion to vertical motion. The other spring (the sear spring) is a wire that coils around the sear retaining pin and runs under the sear pushing it up directly. This spring acts to push the trigger forward indirectly through the sear (sear pushed up -> trigger pushed forward). This spring also works the 4-way indirectly through the sear, trigger, timing rod, and rocker arm. This second spring is by far the stronger of the two, providing most of the force you pull against when you fire the gun. This stronger spring is also the furthest, mechanically, from the mechanism requiring the most force: the 4-way valve. This results in a certain degree of inefficiency. You supply a certain amount of energy compressing or coiling the springs when you pull the trigger, but much of that is lost when you release the trigger in the 4 steps of redirection between the sear spring and the 4-way valve. This is why the horizontal spring described first is necessary to the design: to supply the final bit of motive force to work the 4-way.
Now some ways to work around that.
Quick & Easy Trigger-Job
This one is really easy and gives about 50% of the improvement of a full trigger work-over.
Look at the stock sear spring. You'll notice that one leg starts on one side resting on a vertical ledge in the frame, coils around the sear retention pin, runs under the sear, then coils around the pin on the other side and comes to rest on an identical ledge on the other side. Use a screwdriver to drop one of the legs off it's ledge so it snaps down into the middle of the frame. Tah dah! Instant trigger job. Try pulling the trigger before and after doing this. You'll be amazed that all Typhoons don't come out of Palmer's with this simple, yet very effective fix.
If you're feeling adventuresome, you can even take the spring out and bend it so it doesn't push so hard on the sear. This becomes a bit tricky in that you have to start worrying about still supplying enough energy to work the 4-way.
More Involved Trigger-Job
Since this one is a bit more involved and requires a lot of patience and playing around to get it to work right, I recommend it for people with a thorough understanding of the gun, its inner workings, and timing. With this work done, you are also going to have to be more careful than usual about keeping the gun clean, well oiled, and properly pressure regulated (i.e. not too high a pressure) to prevent 4-way sticking.
Since most of the trigger's return force is required to move the 4-way valve, it stands to reason that you'd want your springs working as much directly on the valve, or as close to it as you can get them rather than on the sear as in the stock configuration. Ideally you'd want springs acting directly on the rocker arm, or better yet, vertically either pushing or pulling the valve piston up. That way you'd eliminate losses translating the force through the sear, trigger, timing rod, and rocker arm.
What I do is remove the sear spring entirely and put in a very light vertical spring between the timing rod and sear (see Big Kahuna picture below) that is just long and strong enough to push the sear back up when the trigger is released. Believe it or not, this is often all that is needed. In many cases, the stock spring behind the timing rod provides enough force to work the 4-way valve. Sometimes, though, you need to replace the spring with one that is longer and/or heavier than the stock one. Slightly repositioning the 4-way valve may also help in getting this to work, but also has great potential to seriously mess up the timing. WARNING: this may not work at all if you have a very sticky 4-way valve. Keep your stock springs (which you KNOW will work) in case you can't get this to work right.
Most Involved! Don't even think of doing this! You fool!!!
I have to say that because suggesting this will almost certainly drive Glenn Palmer to put a contract out on my head. If you try this, don't expect Palmer's to honor their full lifetime warranty on your Typhoon/Stroker.
Most of these mods are shown in the Big Kahuna picture below.
As you may have noticed, the "More Involved Trigger-Job" described above still provides the 4-way return force at right angles to the motion desired through the rocker arm. While a dramatic improvement over the stock configuration it would be better yet to deliver return force directly, vertically to the 4-way valve or horizontal leg of the rocker arm which acts on it. I've finally figured out a good way to achieve this.
First, remove both stock springs, and insert a vertical sear return spring as above. [Glenn Palmer, please skip this next section] Now drill a hole in the trigger frame above and slightly in front of the 4-way valve. Connect a spring under tension between that hole and one of the holes in the horizontal leg of the rocker arm (if no holes in the rocker arm, drill one just outside the part that acts on the 4-way) such that when the trigger is released, it pulls the rocker arm (and thus the 4-way) up. Again, you will have to experiment with this spring to make sure that it is under enough tension to work the 4-way when the gun is under pressure. I've reworked a number of Typhoons and a Stroker (my own marker and a few friends') using this method. Despite the fact that it is considerably more trouble than the second method described above, I think that it is significantly better in that it provides trigger effort just as light, but with greater smoothness and reliability.
The Big Kahuna (Glenn Palmer's Nightmare)
(Stage 4 - Now for you to see)
Below is a picture showing most of what goes into the Big Kahuna. The following things have been done:
- I've installed a vertical push-spring to return the sear and a vertical pull-spring to return the 4-way and trigger. Both of these significantly soften the trigger pull.
- I've replaced the rocker arm with a recut piece to take up more of the slack in working the 4-way, shortening the pull. Remember: there still must be some space around the horizontal leg of the rocker for you to be able to time the 'gun properly!
- I've moved the connection of the timing rod to the rocker arm down one hole. This shortens the trigger pull required to work the 4-way, but makes the trigger a bit heavier.
- You can't see this, but I've polished a small amount off of the bottom-front of the sear where it contacts the trigger. This pushes the fire point back in the trigger pull, allowing me to turn out the trigger stop further.
- I've installed a double-finger trigger - a fabulous mod for the Typhoon all on it's own.
Remember, most of these things require you to retime the 'gun after doing. Don't try any of this unless you know how to time the 'gun.
Sorry, but since Palmers is now doing their own Typhoon trigger-job, I am no longer doing the Big Kahuna Typhoon trigger job for anyone but myself and friends. Palmers' trigger-job is very nice and I strongly recommend it if you're afraid to try this stuff yourself.
Have patience & good luck.
All material at this site is © Ravi Chopra, 1999