We were wondering why one left handed Lyman Great Plains rifle that was failing to go bang: the lock's hammer was not timed to the nipple. The inletting for the lock put the lock too far back and thus the hammer won't hit the nipple squarely. On a percussion gun with a drum, you can rotate the drum to reposition the nipple. However, on a Great Plains you can't do that. The best you can do is to bend the hammer; which I tried but need help in doing.
Left handed Lyman Great Plains issue
- Thread starter 4V50 Gary
- Start date
Interesting problem !!!
Gary,
I've never had to bend a Lyman hammer, in order to make a good "cup-face" contact. I have bent a number of TC's and no heat was required. You "may" get away with not needing any torch work. You may also gain a little length by installing a longer nipple. Good luck and let us know, how you made out. ..
Be Safe !!!
Gary,
I've never had to bend a Lyman hammer, in order to make a good "cup-face" contact. I have bent a number of TC's and no heat was required. You "may" get away with not needing any torch work. You may also gain a little length by installing a longer nipple. Good luck and let us know, how you made out. ..
Be Safe !!!
bedbugbilly
New member
Pahoo has the right fix. My first question was going to be are you sure the correct nipple is installed? If it came with the rifle it should be but you don't mention if your rifle is new or used. Or . . if it is new, are you sure that it came with the correct nipple? "Things" do happen at the factory.
Before bending - try giving Track of the Wolf a call and explain your problem. Maybe they have a nipple that is longer that will fit. If they do . . . buy several so you have some spares.
Just as a side note: I'm not familiar with the GPR . . but I have built a number of rifles over the years. Most locks, when the sear is released allowing the hammer to rotate down . . . the hammer hoas "over travel" so that there is no chance of a space between the cup and the top of the nipple.
This may be a wild comment . . . but have you taken the lock off and manually cocked it, released the sear so it dis-engages the tumbler and gently let the hammer lower? Any chance the sear is catching on the last notch on the tumbler instead of by-passing it so that the hammer goes down tight on the nipple?
If I remember correctly, the GPR utilizes a patented breech. I am not saying your problem doesn't exist, but it sure seems like the tail of the lock (the lock itself) would really have to be canted down in the back to keep the hammer from engaging the nipple. If that is the case . . . then your lock mortise had to be cut "really off" and it doesn't seem like the bolster cut-out on your lock plate would fit very well at all.
Another thing to check would be the tumbler itself. Any chance it is a "faulty" tumbler where the geometry is off so that it doesn't allow the hammer to come in contact? Seems like a "long shot" but I have seen such things on locks when replacing internals.
It really is something that Lyman should "address" and make right?
Let us know what you come up with and good luck.
Before bending - try giving Track of the Wolf a call and explain your problem. Maybe they have a nipple that is longer that will fit. If they do . . . buy several so you have some spares.
Just as a side note: I'm not familiar with the GPR . . but I have built a number of rifles over the years. Most locks, when the sear is released allowing the hammer to rotate down . . . the hammer hoas "over travel" so that there is no chance of a space between the cup and the top of the nipple.
This may be a wild comment . . . but have you taken the lock off and manually cocked it, released the sear so it dis-engages the tumbler and gently let the hammer lower? Any chance the sear is catching on the last notch on the tumbler instead of by-passing it so that the hammer goes down tight on the nipple?
If I remember correctly, the GPR utilizes a patented breech. I am not saying your problem doesn't exist, but it sure seems like the tail of the lock (the lock itself) would really have to be canted down in the back to keep the hammer from engaging the nipple. If that is the case . . . then your lock mortise had to be cut "really off" and it doesn't seem like the bolster cut-out on your lock plate would fit very well at all.
Another thing to check would be the tumbler itself. Any chance it is a "faulty" tumbler where the geometry is off so that it doesn't allow the hammer to come in contact? Seems like a "long shot" but I have seen such things on locks when replacing internals.
It really is something that Lyman should "address" and make right?
Let us know what you come up with and good luck.
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bedbugbilly
New member
I've been thinking au this all afternoon.lk
As I said, I'm not that familiar with the GPR so maybe someone who is can chime in. is there a possibility that the tumbler on a percussion lock is different than the tumbler on a flint lock? i.e. . . . that that the square that the hammer mounts on is different for a flint hammer than for a percussion hammer - position wise - and the wrong one got put in your percussion lock?
Just a thought. Maybe if you gave Track of the Wolf a call they could answer that or help you out?
As I said, I'm not that familiar with the GPR so maybe someone who is can chime in. is there a possibility that the tumbler on a percussion lock is different than the tumbler on a flint lock? i.e. . . . that that the square that the hammer mounts on is different for a flint hammer than for a percussion hammer - position wise - and the wrong one got put in your percussion lock?
Just a thought. Maybe if you gave Track of the Wolf a call they could answer that or help you out?
If I am understanding this correctly, your hammer is hitting the nipple, but at the wrong angle? If this is right, you can get longer or shorter nipples to help the problem. I have also occasionally had to do some dremel work in the past withing the cup on the end of the hammer to change the angle there.
Bending a hammer on a factory inlet Lyman just doesn't seem necessary to me.
Bending a hammer on a factory inlet Lyman just doesn't seem necessary to me.
Only the top of the hammer strikes the nipple. The flat portion of the hammer falls short. The problem lies in the inletting of the lock which is too far back in relation to the drum and nipple. The only solution is to bend the hammer such that it will fall onto the nipple.
BTW, I had to do this on the Traditions Trapper I built and the Spanish 45 rifle that I soldered a rib beneath the barrel.
I'm going to ask another black powder enthusiast to help me. He can hold the torch while the metal is being heated. I can hold the hammer in a vise grip as well as a hammer with which I can pound on it.
BTW, I had to do this on the Traditions Trapper I built and the Spanish 45 rifle that I soldered a rib beneath the barrel.
I'm going to ask another black powder enthusiast to help me. He can hold the torch while the metal is being heated. I can hold the hammer in a vise grip as well as a hammer with which I can pound on it.