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Set trigger question?

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I recently acquired a rifle with double set triggers that requires the rear trigger to be set before the hammer can be brought to full cock position. Is this a common type of set trigger? Most of my other set trigger guns are either single phase or double phase triggers. I have never encountered a gun that required the trigger to be set before the gun can be cocked. This seems to be somewhat risky, as you cannot cap the rifle unless the hammer is back, and at that point the gun has a hair front trigger that could go off accidentally. Lowering the hammer onto a live cap is also not good, especially in a hunting situation. What are your thoughts? By the way, this is not an antique rifle, it is a custom made rifle by TVM back in the 1980's.
 
I’ve seen a few and my thoughts are if a bit more effort was made by the builder then the rifle could be cocked with out having to set the trigger. All the rifles I build with set triggers work with out setting the trigger first.
 
Fyrstyk,
The front trigger bar is being pushed up by the trigger's mainspring. There may or may not be an adjustment screw in the trigger base to control the spring travel. Too much travel causes the sear bar to be too high. This extra height applies pressure on the sear keeping it from engaging in a tumbler notch. If there is no set screw one can be installed very simply if you can drill and tap.
Flintlocklar :wink:
 
If the trigger is a double phase trigger that will fire the gun when the rear trigger is not "set", the trigger assembly is installed too deeply into the stock.

To determine if the triggers are double phase without removing them from the stock, remove the lock from its mortise.
Then, look thru the hole in the stock that the sear arm sticks into when the lock is in place.

If pulling the front trigger raises the blade on top of the trigger up so it can easily be seen, the triggers are double phase.

By lowering the trigger assembly in the stock by using shims or similar items, the rear triggers blade will be lower so it no longer is pressing on the sear arm when it is in the unset condition.

Some double set, double phase triggers have an adjustment screw for the rear trigger spring.
It allows reducing the spring pressure which can help to prevent the problem your having.

IMO, if the trigger assembly is a double set, double phase trigger a more professional fix for the problem is to grind off some of the top of the front trigger's blade.
The way factory set triggers are designed, they usually have extra material on top of the trigger blades so filing them to fit the gun being built is usually required.

If the trigger group is a Single phase, it is designed to only fire the gun if the rear trigger is first set.
Single phase triggers cannot fire the gun unless the rear trigger is first set because the front trigger does not have a blade on the top.

These single phase triggers are purposely made to always be pushing up on the sear arm UNLESS the rear trigger is set.
Setting the rear trigger lowers the blade down so it is temporarily no longer pressing on the sear.
The idea of a single phase trigger always pushing on the sear arm when it is unset is because with this trigger design the lock does not have to have a fly in it to work with the set trigger.
By pushing on the sear when the rear trigger is released, it keeps the nose of the sear well away from the half cock notch. Of course, this makes the half cock notch rather useless but at least the lock will work with a set trigger.

If the trigger assembly is a double set, single phase trigger, it is working like it is designed to work so there is no easy way of fixing the problem except to learn to live with it or replace the trigger assembly with a double set, double phase trigger.
 
Thanks Zonie, you described exactly what I have. I guess I will just have to live with it, cause I don't want to replace the trigger on this custom gun. Just have to be real careful when capping, and double check that the rear trigger is set before trying to cock the gun. I would hate to have the gun go off accidentally because I thought I had set the trigger and had the hammer fall because the rear trigger was not set.
 
Accidents with guns that are preventable are NOT accidents. I believe if the problem is as Zonie suggested, a too deeply set trigger, that I would try shimming etc. Likely can be repaired (unless it WAS designed to work as you report it does?). Just a thought :idunno: If it was one of my favorites I'd wanna keep it as is too but I would sure try to remove the possibility of it going off before I said so.
 
Just have to be real careful

:applause: That is the key. Whatever you have, be careful.
Modern Remington rifles have a well earned reputation for unintended discharges. They have made TV because people have been injured when this happened. Those rifles may have gone off unintentionally, but the the injuries happened because the handler was not careful about where it was pointed.
For our ml rifles, some folks, my wife being one, prefer the single phase trigger. I dunno why :idunno: but she does and that is part of why our game is so unique and encompasses many unique people.
 
Having accidentally snapped my set trigger off with the rifle at half cock more times than I care to admit, I can see the draw to one that wont let you cock the gun at all unless its set. If the set goes off with the hammer all the way down I dont have to worry about damaging my lock. Not so when in the half cock notch.
 
I played with the adjustment screw and now have it adjusted such that when you set the rear trigger, then pull the hammer back, the hammer stops in the half cock notch. Before this adjustment, I had to pull the hammer all the way to full cock which I thought was not very safe. I fell better with this arrangement now. I can cap the rifle with the hammer at half cock. I still have to remember that once I pull the hammer to full cock, the triggers are set and only about a pound of pressure is required to fire the gun at that point.
 
One of our members reminded me of the adjustment screw that is on some double set, single phase triggers so I should add the following thoughts.

Some single phase triggers come with an adjustment screw under the mainspring. It is located behind the rear trigger.

Screwing this in reduces the spring loaded travel of the mainspring so it cannot deflect the rear triggers blade as far upward and this can (sometimes) result in allowing the lock to be cocked even though the rear trigger is not first set.

If the single phase trigger does not have a screw, one could drill and tap a hole under the free end of the spring and install a set screw to do the same task as the triggers that already have this feature.

A word of caution about adjusting the mainspring tension screw is in order.

Because the mainspring is pushing the rear trigger blade up against the sear arm, although using the screw to reduce the mainsprings pressure will reduce the trigger's pressure on the sear arm, if the pressure is not reduced far enough, the spring will be trying to prevent the nose of the sear from fully engaging the full cock notch. This could result in allowing a fully cocked gun to fire if the stock is bumped.

The blade on the rear trigger must be positioned to allow the sear to fully engage the full cock notch.

Because screwing the spring adjustment screw in reduces the amount of force the rear trigger's blade can produce, if it is screwed in too far, the trigger may not have sufficient energy to release a fully cocked lock so, adjusting this screw is sort of a balancing act.
Too far in = bad. Too far out = bad. Somewhere in between = good.
 
I'll post my picture of a single phase set trigger made in 1837 by J Fehr of Nazareth PA.

36083430401_50082c637f_z.jpg


As can be seen, there is no lever on the forward trigger. There is a strong spring that holds the rear lever up preventing the sear from entering the notch unless the triggers are set. There is a screw that adjusts the engagement of the rear lever with the setting trigger.
 
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