• This community needs YOUR help today. We rely 100% on Supporting Memberships to fund our efforts. With the ever increasing fees of everything, we need help. We need more Supporting Members, today. Please invest back into this community. I will ship a few decals too in addition to all the account perks you get.



    Sign up here: https://www.muzzleloadingforum.com/account/upgrades

Hammer (cock) on Great Plains Rifle

Muzzleloading Forum

Help Support Muzzleloading Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Roguedog

45 Cal.
Joined
Jul 21, 2012
Messages
770
Reaction score
1
For those of you who have the Lyman Great Plains Rifle in flintlock, how many of you have the original cock? In reading some previous posts, and based on my own very limited experience, it does appear that the geometry of the Lyman cock is less than ideal. With mine, it is pretty much impossible for me to put the flint in "bevel up" and still be able to make decent contact with the frizzen. As others have mentioned, I can aid this situation by adding an additional layer of leather underneath the flint. Even then, I still have to put the flint in "bevel down" just to get the extra height I need to make good contact with the frizzen. The problem I have then is that of the angle in which the flint hits the frizzen. Seems to be to horizontal. It's almost like it's hitting it head on rather than slicing down upon it. I will continue to experiment and adjust and will probably get it working fine but I was just curious about how many may have replaced their cocks with something different such as the Thompson Center. I just my few shots the other day, I started to get the feeling that a lot of sparks is a good thing.

Jeff
 
I can't really make a comment since I've had my lyman lefty flinter for about 2 weeks. But I did the extra leather under the flint, and while not ideal, I've fired over 40 shots on a Fuller black flint and have not had a missfire yet :thumbsup:
 
I don't bother with the extra leather under the flint, just put it in bevel down. It hits a little low on the frizzen but sparks very reliably, actually even bevel up it sparks well. I just never saw the need to do anything else about it.
 
Thanks guys. I will definitely try these suggestions. It's good to know that most folks are getting reliable sparking from their Lyman cocks, despite not having the greatest geometry. As I said, I'm just gonna shoot the heck out of the gun and figure out exactly what it likes.

Jeff
 
"... It's good to know that most folks are getting reliable sparking from their Lyman cocks, ..."

There is no doubt the Lyman lock will work as it comes from the box. The key is that word “reliable”.
Standing in the back yard or on the firing range a lot of guns work. And if it does mis-fire so what?
I have an unaltered Lyman lock that I use for all sorts of testing. It works very well and if it doesn't, so what? I have an unaltered TC, early version, I purposely leave that way. If it mis-fires, so what.
Now on-the-other-hand, if you want the GPR 99.9% reliable under all conditions, you will need to do some mods to it.
And on a GPR, the very first thing is a new touch hole liner or at least drilled out to .070.
The hammer cock is second to that. With these two things done the GPR shoots as good as any gun there is. Much to the dismay of some folks here but it will.
 
Ebiggs,
Are you suggesting that in order to get maximum efficiency from the GPR, the T/C hammer cock is needed?

Jeff
 
Mine has the original hammer. Always had the best luck putting the flints in bevel down as well.
 
Roguedog said:
Ebiggs,
Are you suggesting that in order to get maximum efficiency from the GPR, the T/C hammer cock is needed?
Jeff

No, not at all but it does eliminate a problem that the GPR suffers from. It depends on yourself and how you shoot and use your gun. If you want the best results with the most reliability with the least effort, than, yes! :thumbsup:

Some guys seem to be quite satisfied with the way they come. I don't understand them but to each his own. The worst part and is a mandatory to change item is the touch hole liner. The cock is nice to change but can be overcome with a little additional effort as a leather under the flint. Or if you are OK with partial reliability, leave it as is.
The choice is yours. :hmm:
 
For those of you who have the Lyman Great Plains Rifle in flintlock, how many of you have the original cock? In reading some previous posts, and based on my own very limited experience, it does appear that the geometry of the Lyman cock is less than ideal. With mine, it is pretty much impossible for me to put the flint in "bevel up" and still be able to make decent contact with the frizzen. As others have mentioned, I can aid this situation by adding an additional layer of leather underneath the flint. Even then, I still have to put the flint in "bevel down" just to get the extra height I need to make good contact with the frizzen. The problem I have then is that of the angle in which the flint hits the frizzen. Seems to be to horizontal. It's almost like it's hitting it head on rather than slicing down upon it. I will continue to experiment and adjust and will probably get it working fine but I was just curious about how many may have replaced their cocks with something different such as the Thompson Center. I just my few shots the other day, I started to get the feeling that a lot of sparks is a good thing.

Jeff
I have the original cock, but after traditional browning the cock screw is frozen in place.
I love the rifle, but afraid I must replace the cock. I don't need to replace the whole set.
Any suggestions?
 
Sounds like you are chasing a problem that does not really exist.

Bevel up or down, no big deal.

You do what the rifle wants.
 
I have the original cock, but after traditional browning the cock screw is frozen in place.
I love the rifle, but afraid I must replace the cock. I don't need to replace the whole set.
Any suggestions?
Soak it in a good penetrating oil for a day or two. Then, carefully try turning the screw back and forth with a screw driver.
If that doesn't break it loose, use some locking pliers like Vise-Grips to grab the screw head and turn the screw back and forth. It should break loose.
If that doesn't do it, use a torch to heat the screw and use the locking pliers again. It should break loose. Once it does, add more oil and rotate the screw back and forth to work the oil down into the threads. It should then unscrew.
 
Back
Top