New (preassembled) Investarms Bridger Hawken .50 cal, percussion: Trigger, hammer question

[stewall]

Just received the above and find the the trigger is not working properly in that when pulling from half cock to full cock, I hear several clicks and, in thinking that the gun is fully cocked, I release it and it springs all the way forward (which would discharge the rifle if it was loaded - in my case it was not)
It was my understanding that if your thumb should slip from the trigger whist moving from half to full cock, that the hammer should return to the half cocked position and not 'fire'. Am I wrong? BTW. It will go into full cocked position and stay there but the half cocked position is barely above the nipple
. . . Also, with this particular rifle, I cannot get a balance between the front and rear triggers (trigger main spring adjusting screw and hair trigger adjusting screw). At best, getting the rear trigger into position takes a lot of squeezing to set it . Out of the box, it wouldn't set at all. It just feels all wrong to me.
Any thoughts, please?

 

[deermanok]

Not sure if I'm following you. The hammer won't stay at full cock?
They're not designed to fall on half cock if you should let go of the hammer while cooking.
The spring adjusting screw might be set too tight. You could try backing off on that screw a turn or two.

 

[Grenadier1758]

One of the clicks you hear when going from half cock to full cock is the sear riding over the fly and pushing the fly forward to now cover the half cock notch. Once the fly is covering the half cock notch, the hammer must be fully lowered to allow the fly to uncover the half cock notch. That is why the sear is not falling into the half cock notch. You need to pull the hammer fully back. Eventually you will know the number of clicks that are required for the sear to enter the full cock notch and how far to pull the hammer back. Don't rely on the number of clicks to determine if the hammer has been pulled far enough to be in full cock.

For some locks, the half cock position barely clears the nipple leaving little to no room to put a cap on the nipple. To me that's poor design of the notches in the tumbler. Not much can be done about that.

There is a strong spring that presses on the set trigger lever to drive it into the sear to knock the sear out of the full cock notch. Often that spring is over tightened, and the set trigger will be difficult to set. Back the tension down on the spring that drives the rear trigger. You don't need to impact the sear that hard, just enough to tap the sear.

 

[stewall]

Not sure if I'm following you. The hammer won't stay at full cock?
They're not designed to fall on half cock if you should let go of the hammer while cooking.
The spring adjusting screw might be set too tight. You could try backing off on that screw a turn or two.

Thanks, "deermanok": The hammer will stay at full cock. The concern is that when pulling it from half to full, then if my finger slipped the hammer would (should) simply return to the half cocked position and NOT return all the way to hit the cap and discharge.
"Grenadier1758": I also have a Traditions Trapper pistol and on that, the trigger resumes the half cocked position in the event of not fully cocking or a thumb slip. As it stands, I have to pull the trigger beyond half cock and hold it there whilst inserting a cap. Not wanting a accidental/negligent discharge this concerns me.
Messing with the screws (main spring and hair trigger adj. screws) didn't get me where I wanted it.
I have spoken to MuzzleLoaders.com and they are sending me a new trigger.
Thank you both for your comments and advice.

 

[SDSmlf]

Just received the above and find the the trigger is not working properly in that when pulling from half cock to full cock, I hear several clicks and, in thinking that the gun is fully cocked, I release it and it springs all the way forward (which would discharge the rifle if it was loaded - in my case it was not)
It was my understanding that if your thumb should slip from the trigger whist moving from half to full cock, that the hammer should return to the half cocked position and not 'fire'. Am I wrong? BTW. It will go into full cocked position and stay there but the half cocked position is barely above the nipple
. . . Also, with this particular rifle, I cannot get a balance between the front and rear triggers (trigger main spring adjusting screw and hair trigger adjusting screw). At best, getting the rear trigger into position takes a lot of squeezing to set it . Out of the box, it wouldn't set at all. It just feels all wrong to me.
Any thoughts, please?

Guessing your trigger is very similar to the one in the photograph below (I believe it is from a TC Seneca) that I took to explain some trigger adjustment for someone.

In the first photograph the arrow is pointing at the screw that will adjust the amount of tension on the set trigger. You can back this screw off to reduce the amount of force to ‘set’ the trigger, but as @Grenadier1758 mentioned, you still need enough tension or force to trip the sear lever on the lock. Once you have found the minimum force required (trial and error adjustment of the screw), tighten the screw a half to a full turn (safety margin). Confirm it is still satisfactory, and then you may want to lock it in place with something like nail polish (I use red so I can easily see it). Make sure the trigger is fully lock into place in the stock when testing its function. If it is lose or out of position it will perform different.

To adjust the ‘hair’ trigger, with trigger assembly out of the gun, set the trigger and turn the screw between the triggers until the trigger pops. Then back off the screw a minimum of a half turn, though I would suggest a full turn for safety reasons. Lock in place with nail polish. There is a chance that the hair trigger adjustment screw will be too short and have no influence on the hair trigger pull. Most recent Lyman GPRs made by Investarm that I have seen were set up that way. You may need a longer screw to make adjustments.

 

[Gtrubicon]

I have an investarm bridger hawken, I can’t get a cap on it at 1/2 cock either. I really like the rifle, very accurate.

 

[stewall]

SDSmlf: Thanks for the above diagram and explanation. Having removed it I adjusted as you say. I have got it working but it is still a heavy, unpleasant trigger. It is also quite rough and would need polishing to make it anywhere near acceptable. My trigger has the two adjustment screws under the trigger, but the theory is the same. It actually feels as though the spring if far to strong.
I compared the trigger to the Trapper and the Trapper does return to half cock if slipped whereas the Hawken does not - once taken beyond half cock, you either fully cocked it or it slams back down on the cap/nipple.
Gtrubicon: Frankly I think the cap/half cock distance is unacceptable. The solution is to either thumb back and hold it while placing the cap, or fully cock it and place it. Seems like it introduces an unnecessary element of danger, especially seeing safety is a foreword in gun ownership and use. Another good reason to absolutely ensure the muzzle is pointing down range at all times.

 

[SDSmlf]

SDSmlf: Thanks for the above diagram and explanation. Having removed it I adjusted as you say. I have got it working but it is still a heavy, unpleasant trigger. It is also quite rough and would need polishing to make it anywhere near acceptable. My trigger has the two adjustment screws under the trigger, but the theory is the same. It actually feels as though the spring if far to strong.
I compared the trigger to the Trapper and the Trapper does return to half cock if slipped whereas the Hawken does not - once taken beyond half cock, you either fully cocked it or it slams back down on the cap/nipple.
Gtrubicon: Frankly I think the cap/half cock distance is unacceptable. The solution is to either thumb back and hold it while placing the cap, or fully cock it and place it. Seems like it introduces an unnecessary element of danger, especially seeing safety is a foreword in gun ownership and use. Another good reason to absolutely ensure the muzzle is pointing down range at all times.

Could you post a few pictures of your trigger setup? Someone may see something that will ‘trigger’ a helpful suggestion to help solve the challenge you are facing.

 

[necchi]

Seems like it introduces an unnecessary element of danger, especially seeing safety is a foreword in gun ownership and use.

Your right.
But these are "replica" firearms that still have 1800's design and technology. They simply do not have 21st century advancements.
Your rifle is functioning as designed.
Full-cock too cap, then manual functioning of the trigger/hammer, down, then back into a half-cock/safety position, was/is the proper technique.
(Yes, you have to be in full control of both finger and thumb, while knowing the gun is loaded)
A finer balance of the trigger/sear break point can be made as already described (but there is a learning curve).
If it's any help, the Traditions Trapper pistol trigger set-up is opposite of the Hawken style rifles,, comparing them will only cause confusion

 

[flntlokr]

Always a good idea to apply a bit of inletting black to the sear and trigger bits that have to move freely; very often the factory 'one size fits all' inletting needs touching up in order for all to work properly.

 

[Snake Pleskin]

Guessing your trigger is very similar to the one in the photograph below (I believe it is from a TC Seneca) that I took to explain some trigger adjustment for someone.

In the first photograph the arrow is pointing at the screw that will adjust the amount of tension on the set trigger. You can back this screw off to reduce the amount of force to ‘set’ the trigger, but as @Grenadier1758 mentioned, you still need enough tension or force to trip the sear lever on the lock. Once you have found the minimum force required (trial and error adjustment of the screw), tighten the screw a half to a full turn (safety margin). Confirm it is still satisfactory, and then you may want to lock it in place with something like nail polish (I use red so I can easily see it). Make sure the trigger is fully lock into place in the stock when testing its function. If it is lose or out of position it will perform different.
View attachment 144897
To adjust the ‘hair’ trigger, with trigger assembly out of the gun, set the trigger and turn the screw between the triggers until the trigger pops. Then back off the screw a minimum of a half turn, though I would suggest a full turn for safety reasons. Lock in place with nail polish. There is a chance that the hair trigger adjustment screw will be too short and have no influence on the hair trigger pull. Most recent Lyman GPRs made by Investarm that I have seen were set up that way. You may need a longer screw to make adjustments.
View attachment 144908

Mine may have this issue? Any suggestion on where to get the longer screw and the proper size, thread etc?

 

[Grenadier1758]

You should be able to get the replacement screw at your local full-service hardware store. Remove the screw from your trigger plate and put it in a small bag. these tiny screws can get lost pretty easily. The full-service hardware store will have a trial board to determine the screw size and thread pitch. Buy a longer one from the selection available.

 

[Snake Pleskin]

You should be able to get the replacement screw at your local full-service hardware store. Remove the screw from your trigger plate and put it in a small bag. these tiny screws can get lost pretty easily. The full-service hardware store will have a trial board to determine the screw size and thread pitch. Buy a longer one from the selection available.

I am thinking since the Investarms is made in Italy, we are probably talking metric?

 

[Grenadier1758]

The screw will probably be metric. Full-service hardware stores will stock metric screws.

 

[Snake Pleskin]

The screw will probably be metric. Full-service hardware stores will stock metric screws.

thanks, I will check it out today!

 

[SDSmlf]

Mine may have this issue? Any suggestion on where to get the longer screw and the proper size, thread etc?

I don’t recall you mentioning who made your trigger/gun, but if Italian or Spanish, likely metric. I believe the GPRs (Investarm) I had changed took a M2.5 x 0.45 and most TCs use a 3-56 screw for example, but the size to fit your gun needs to MEASURED and CONFIRMED. I am just working from memory.

You should be able to get the replacement screw at your local full-service hardware store. Remove the screw from your trigger plate and put it in a small bag. these tiny screws can get lost pretty easily. The full-service hardware store will have a trial board to determine the screw size and thread pitch.

The full-service hardware store is a place to start, but the hardware stores I frequent usually don’t have the smaller screw sizes, usually called scientific and instrument sizes. You can probably get an assortment pack from Amazon (likely Philips headed) or Brownells, which I believe will have some with slotted heads.

 

[Snake Pleskin]

I don’t recall you mentioning who made your trigger/gun, but if Italian or Spanish, likely metric. I believe the GPRs I had changed took a M2.5 x 0.45 and most TCs use a 3-56 screw for example, but the size to fit your gun needs to MEASURED and CONFIRMED. I am just working from memory.


The full-service hardware store is a place to start, but the hardware stores I frequent usually don’t have the smaller screw sizes, usually called scientific and instrument sizes. You can probably get an assortment pack from Amazon (likely Philips headed) or Brownells, which I believe will have some with slotted heads.

It is Italian and probably metric. I was at Loews /Home Depot and they have nothing that s,all. So, probably try Brownells or if not them Amazon. Even the instructions that came with the kit do not list the screw sizes, not even the schematic!

 

[SDSmlf]

It is Italian and probably metric. I was at Loews /Home Depot and they have nothing that s,all. So, probably try Brownells or if not them Amazon. Even the instructions that came with the kit do not list the screw sizes, not even the schematic!

What diameter is the screw? That and it likely being metric will narrow things down.

And I do not think Lowes is the type of full-service hardware store @Grenadier1758 was suggesting.

 

[Grenadier1758]

I was thinking Ace Hardware.

 

[Snake Pleskin]

I was thinking Ace Hardware.

none around me