Thompson center old or new cock?

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TerryK

40 Cal.
Joined
Jan 3, 2014
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I looked for pictures, but I can't determine if this is the old or newer version cock. It is pretty good at eating up flints. I hope I can get something friendlier to flints.
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Thanks SMO. I guess that is good news, because maybe a new style hammer will be easier on the flints.
I also saw discussion that a new Lyman frizzen modified by RMC helps too. I don't know if that is true.
The Hawken I have has a Green Mountain 15/16 inch barrel in 54 caliber. For a factory lock it is super fast and reliable.
 
Yours appears too be the old style....
Notice the “notch” in the rear of the hammer.
D1AD7E1C-C654-40A2-856E-AEBD4A7DEF50.jpeg



The only experience I have with TC flintlocks is with a.50 cal Renegade, I’ve never had any issue with its factory lock what so ever..

G/M makes an excellent barrel as well.
 
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So the Lyman frizzen geometry makes up for the old cock? It looks more curved than the Thompson frizzen.
I just put in a new flint, and it broke in two pulls.
RMC is close to my house, so I can run over there when they open back up.
 
Are you using real flint or the engineered flints? I stopped using the ground down flints and only use English black flint. There are no guarantees on any flints, as to how many times they will work with either kind of flint. I have seen the English break after a few shots and had some last until they were too short to fit in the jaws of the lock.
 
What size are your flints?
I think I used 5/8 x5/8 in mine..could have been 3/4 x 5/8’s it’s been awhile...

I don’t think just changing the frizzen will help with the geometry of the lock.. My understanding it was too do with the angle of the cock..It appears the new cock is talker than the older one and more at a 90 degree angle too the frizzen..
 
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You may need to replace both the frizzen and the hammer, from what I remember. Otherwise you can get a L&R RPL replacement lock. It will take a bit of fitting, instructions are included. If you go that route, be sure to match the pan with the touch hole (don't ask how I know that!); also to file down the lock to fit the inlet, not taking off wood to match the lock (again, I speak from experience).
 
I am using blonde french, black english, and german jasper?. They all crumble. It sparks well and its reliable, but it is a flint smasher. I tried shimming the leather, longer and shorter flints, all with the same results.
I have a RPL on a renegade. No issues with that one. I think the lock is faster on the RPL, but I think the barrel chammber is slower.
I thought of getting a RPL for the Hawken, but I was hoping for an easier solution.
 
So the Lyman frizzen geometry makes up for the old cock? It looks more curved than the Thompson frizzen.
I just put in a new flint, and it broke in two pulls.
RMC is close to my house, so I can run over there when they open back up.
No, the Lyman frizzen geometry does not compensate for the old TC cock. The modified Lyman frizzen has a better heat treat than the old case hardened TC (they worked, but you could sometimes wear through the case hardening). The old cock design works (hits lower on the frizzen), I have just found it a bit rougher on flints. I have purchased a few of the new design cocks from the Gun Works. I’d email or call (talk to Suzi). I see a lot of other people selling the old design, and that is not want you want.
 
I just noticed in your pic the flint is not all the way back in the jaws of the cock??
Was that intentional?

70D0CA72-0151-47C3-B84C-8252F27439E9.jpeg
 
Just realized you were using ‘cut’ flints. Personally, have never had any luck with them in any muzzleloader. Found them to be done after only a few shots, but others do seem to like them. You may want to try some knapped flints.
 
That cut flint is a sythetic. RMC calls it German Jasper, and it is their hardest flint. They are short, and by the way 7 bucks each. I swapped it out for todays hunt with a longer blonde french. I have to say the jasper appears harder.
 

Not sure if it really matters.......... but the lock plate in the "old" cock picture is really from a newer style TC lock.
And the plate in the "new" is from an older style lock. Looks like someone switched the cocks?

Look at SMO's picture in thread #4. That's the way my old TC is setup, not as shown in thread #2
 
I think my .50 cal. TC has the old lock. This had a percussion lock with a drum when I got it. I bought a flint lock, took the drum out, screwed in the vent and converted it to flint. It is the only one like this I have.
 

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I agree 1sgt, the cock I think is the old style on both locks.
However the scroll patterns are different on the lock plates......

Like MJ posted above looks like someone has switched cocks..
Which I’m sure has happened dozens of times over the years....

Or is that just the difference in percussion & flint lock plates design?

Another thing I’ve noticed in the pics above. Some cohave scroll work & some don’t...
So TC must have changed designs over the years.
But that would have nothing too do with the locks geometry..

Ive owned a few TC ‘s over the years and never really paid much attention too their scroll designs... I mostly just shot them & cleaned them.
 
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I agree 1sgt, the cock I think is the old style on both locks.
However the scroll patterns are different on the lock plates......

Like MJ posted above looks like someone has switched cocks..
Which I’m sure has happened dozens of times over the years....

Or is that just the difference in percussion & flint lock plates design?

Another thing I’ve noticed in the pics above. Some cohave scroll work & some don’t...
So TC must have changed designs over the years.
But that would have nothing too do with the locks geometry..

Ive owned a few TC ‘s over the years and never really paid much attention too their scroll designs... I mostly just shot them & cleaned them.

It looks like TC did make some changes over the years. When I purchased the lock I thought it was a TC lock, but may have been Investarms/Lyman or other. It fit in, I did have to remove a little wood for one of the bridle screw heads.

I once heard TC sold a percussion lock and drum as a conversion kit for someone with a flintlock to convert to percussion. I don't know how popular they were.

It sparks pretty good if I get the flint where it needs to be. I need to shoot it more.
 

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