Investarms Plains Pistol Half-Cock Not Secure

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Frankdkk

32 Cal
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Just received Investarms 54cal Plains Pistol. Concern is that after I pull jammer back to safe half-cock position, and I pull hammer back a little bit more but short of firing position - I find that hammer goes freely to firing nipple if I let go of it. Is this normal, or is it a warranty issue?
Thanks,
 
Just received Investarms 54cal Plains Pistol. Concern is that after I pull jammer back to safe half-cock position, and I pull hammer back a little bit more but short of firing position - I find that hammer goes freely to firing nipple if I let go of it. Is this normal, or is it a warranty issue?
Thanks,
can't help u friend all this stuff is new to me. I'm sure someone will see your post and help u soon. be safe
 
first thing to do is to take the lock out of the rifle and see if the half cock works properly out of the stock.

If it does work out of the stock, then you have some inletting issues and you need to figure out where it is binding things up.
If it also doesn't work outside of the stock that is an issue I can not help with. Type of job I farm out to a skilled gun smith.

but yeah if it is an inletting issue you can fix that pretty easy
 
Investarms plains pistol has no set trigger and no fly. Polishing parts is limited because it's a coil spring-plunger lock.

Check that it's clean. Check that the arm of the sear isn't rubbing inside the inlet. Don't over tighten the lock, as it can cause binding in the sear arm. Check the nose of the sear and the half cock notch are both nice and square and not worn or damaged.
 
The half cock notch is not a safety like a modern gun. I bet investarms will tell you letting the hammer fall while cocking the gun is a user error and not a mechanical problem.
 
Agreed, if it has a set trigger it has a fly, if it has a fly you are probably doing exactly what smokeum says.
This one has a single trigger (no set trigger) and it has a percussion ignition.
That said, I don’t know if this pistol has a fly part in the trigger like my Kibler flintlock rifle - I haven’t taken the pistol lock apart yet.
So if this a normal functioning on the pistol I will definitely not be trusting the halfcock position for safety. I think I’ll start by getting or making a cover for my cap nipple.
Thank you for the replies.
Frank

P.S. - I also sent a note to gun manufacturer Investarms about this. I’ll of course share any reply I get from them.
 
Investarms plains pistol has no set trigger and no fly. Polishing parts is limited because it's a coil spring-plunger lock.

Check that it's clean. Check that the arm of the sear isn't rubbing inside the inlet. Don't over tighten the lock, as it can cause binding in the sear arm. Check the nose of the sear and the half cock notch are both nice and square and not worn or damaged.
Thank you! I will certainly do that.
I have not yet researched if or how I can dismantle or polish the lock mechanism - but based on previous experience with my Uberti Colt replica pistols I definitely plan to do whatever I can do.
 
The half cock notch is not a safety like a modern gun. I bet investarms will tell you letting the hammer fall while cocking the gun is a user error and not a mechanical problem.
I now suspect that will be the case. As stated above I will certainly share whatever Investarms has to say about this. Thank you for the reply.
 
I have the same pistol in 50 cal. and it does the same thing. I was at the range with it and was talking to a gunsmith that was finishing up work tuning a rifle he was working on, about what I thought was a problem. He told me that was supposed to work that way. It's a de-cocking function, so you didn't have to fully cock the pistol and pull the trigger to let the hammer down. I don't think it's a mechanical malfunction. make sure to pull the hammer all the way back, you'll hear 3 clicks, first is half cock, second click is the de cocking function, and third click is full cock. I know it doesn't seem right but since we have the same model and same function??
 
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I have the same pistol in 50 cal. and it does the same thing. I was at the range with it and was talking to a gunsmith that was finishing up work tuning a rifle he was working on, about what I thought was a problem. He told me that was supposed to work that way. It's a de-cocking function, so you didn't have to fully cock the pistol and pull the trigger to let the hammer down. I don't think it's a mechanical malfunction. make sure to pull the hammer all the way back, you'll hear 3 clicks, first is half cock, second click is the de cocking function, and third click is full cock. I know it doesn't seem right but since we have the same model and same function??
I would love to see pictures of this de-cocking mechanism. Please post pictures so we can all see how this works.
 
Just received Investarms 54cal Plains Pistol. Concern is that after I pull jammer back to safe half-cock position, and I pull hammer back a little bit more but short of firing position - I find that hammer goes freely to firing nipple if I let go of it. Is this normal, or is it a warranty issue?
Thanks,
Is this with your finger on the trigger or completely off the trigger? If the trigger is pulled this is exactly how it should work.
 
I have not heard of a decocking mechanism and the user manual for this gun makes no mention of it. I wouldn't do it this way, but manual says to place a cap at full cock then press the trigger and carefully lower hammer to half cock. Would seem unnecessary if there's a decocker in there somewhere.
 
Is this with your finger on the trigger or completely off the trigger? If the trigger is pulled this is exactly how it should work.
And Phil is right, a small amount of pressure on the trigger -from finger or spring or just sitting too high in the mortise, could cause the sear to skip the half cock notch.
 
Never heard of a de-cocker on a lock.
Pull hammer all the way to full cock. Next pull the hammer back a little more. While holding the hammer back, pull the trigger and lower hammer simultaneously. It should go all the way to the nipple. If it catches, you have a sear issue. Check the notches and the sear. Might have a large burr on the half cock notch. Its Its not riding over it. Or protect the nipple, go to full cock and and pull the trigger. It shouldn't hesitate any to strike the nipple.
I'm no expert but I have worked on a few of them. Have not failed to get them in good working order. And as others have mentioned, make sure there are no inletting issues.
 
I have the same pistol in 50 cal. and it does the same thing. I was at the range with it and was talking to a gunsmith that was finishing up work tuning a rifle he was working on, about what I thought was a problem. He told me that was supposed to work that way. It's a de-cocking function, so you didn't have to fully cock the pistol and pull the trigger to let the hammer down. I don't think it's a mechanical malfunction. make sure to pull the hammer all the way back, you'll hear 3 clicks, first is half cock, second click is the de cocking function, and third click is full cock. I know it doesn't seem right but since we have the same model and same function??
Thank you. That is exactly what mine is doing!
 
2017 gun magazine article mentions and has a pick of the pistol showing a fly 🤔
GUNS-02-1217-4.jpg
 
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