RPL lock & Fitting for TC- What do I need to know?

[Oil Derek]

For those that have done these L&R replacements, what crucial makeovers and steps need done?  I have zero rifle building experience.  I thought this might be a place to get my feet wet.  I do have a couple of local experienced builders as an out. 

[ScottH]

The TC lock is powered by a coil spring. The RPL lock has a leaf spring. There will need to be a fair amount of wood removed to accommodate the new lock with its different spring. That is the biggest difference I'm aware of.  I put a RPL lock into a stock that Pecatonica River made as a TC replacement stock in curly maple.

[Oil Derek]

Thanks Scott. 

I was basically aware that it will require more in letting.  I don’t have inletting black and will need a substitute.  Wasn’t sure if additional work is advised to the lock itself.

[Eric Krewson]

Here comes broken record Eric, at least that is what I feel like when I answer this question.

The RPL lock is not a drop in by any means, TCs are not the cookie cutter duplicates one might expect, they can very slightly from gun to gun.

Some people can put this lock in their TC fairly easily but most find it to be a challenge.

This will give you an idea of what I considered a "nightmare". I had to move the barrel back almost 1/4" to get the pan in the right place, I had to cut off a little of the under rib to move the barrel back, had to re-drill the lock bolt hole because the TC one didn't line up with the blind L&R socket on the bridal. I had to grind off the back of the hooked breech to accommodate the new lock bolt and had to grind down the side of the barrel to get the lock flush with the barrel as well as fill the gaps in the lock mortise where the lock plate was too small. I almost forgot, I had to remove a tremendous amount of wood for the lock internals. The stock was a percussion stock that I changed over to flint.




It came out OK, the lock sparked well, the rifle I put together had a new old stock TC flint barrel, I never shot the gun, I sold it to a guy who has never shot it. It is still pristine. You can see the fill in shims at the tail of the lock. The lock inletting is entirely my doing, the lock plate was slightly larger than the TC inlet.


As you can see, I did a lot of polishing on the lock parts, I then turned the lock grey to match the barrel I blued and rubbed back,

[Eric Krewson]

If I were to install another of these locks in TC, the first thing I would do is to screw the lock bolt into the blind socket on the bridal and tighten the screw just enough to see where the lock is going to be in relation to the TC inlet and touch hole. I assumed the bolt alignment would be correct after I inletted the lock into the existing TC lock inlet as best I could, it was way off which caused me to do the other work to correct it. 

[TDM]

Eric, great work, and you certainly covered the issues involved. I've had the same issues with the RPL locks, poor vent hole to pan alignment and a need to remove, in my opinion, an excessive amount of wood. I've also found these locks require quite a bit of polishing to tune them to get a decent lock speed.

[Oil Derek]

Thank you Eric!  Sorry to cause you a repeat … my bad as I forgot to do a search first.  However I went to the tutorial areas and read what I could find concerning lock inletting.

I’ll assess first then decide.  Not my flint gun but probably 40 yo.

[Steeltrap]

I have, what's remaining of my original 1979 T\C Hawken 50 cal, worked on the T\C lock. The only remaining components that were original are the stock, 80% of the furniture, and the lock. This rifle was ment to be used....and is still used... solely for the post Christmas Pennsylvania flintlock deer season. And it does that job quite well....if I do my part.

The trigger pull on this lock was 10+lbs as measured with my Lyman Digital trigger pull gauge.

So, me not being a fan of the set trigger, I disassembled the T\C lock, and using a Dremel, a soft material buffing wheel, and Flitz, went to work on every part of the lock that "touched" or "moved against" any other part of the lock. Doing this reduced the pound pull down to about 7.5lbs (IIRC).

Now, that is much higher than my other flintlock's that have L&R locks. Those other firearms also have a proper trigger pin placement to get the pull-LBS to a "reasonable" number. However, because I use this flintlock in (usually) very cold weather, I like the heavier pull. My fingers are usually cold and judging the trigger at the "critical time" helps with a trigger that has some pull weight to it.

Yes, I know the lock is not "PC"...but the entire firearm isn't. The rifle does what it's called upon to do, and the whitetail don't seem to care if the ball comes from a "Flint-in-stien" or a PC firearm.

I'd just suggest trying to polish it up to reduce trigger pull. Be aware to check the lock...post work....so that it still functions safely and won't "fire" with just a bump against something.

FWIW

[Oil Derek]

Thanks TDM and Steeltrap on polishing aspect.

[Eric Krewson]

Here is what I have found on every TC trigger I have worked on; the trigger bar is as rough as a washboard, polishing it and the sear where it contacts the trigger bar will drop the trigger pull a few pounds.

Before;



And after;

[Eric Krewson]

Here is the worst one I worked on; you can see how rough the trigger was where I didn't polish it. Polishing the trigger bar dropped the trigger pull from 9# to 6#. Sorry for the out of focus picture, I had moved on and sold the rifle before I downloaded the picture, I couldn't go back and take another one.

[recurve]

not to Hi jack but I just replaced the above traditions lock with the L&R and what a great improvement    I did need to remove a lot of wood breaking into the ramrod  channel and had to reshape the trigger. but well worth the effort! 

[satwel]

I installed an RPL last winter on a .45 Hawken I bought as a kit in the mid 70's. I didn't expect it to be a drop in fit, but I had to remove a lot of wood in the lock mortice before as it was even close to fitting. Try as I might, I could not get the entire length of the pan bolster to fit tight against the barrel. There was a small gap at the front end of the bolster. I got frustrated and finally decided it needed a front lock screw. I drilled and tapped a hole in the lock plate and used the lock bolt from the original lock. That pulled the bolster tight against the barrel along its entire length.

The next problem was how to fill the two gaps between the new lock plate and the stock. Luckily I had some scrap walnut that matched the rest of the stock. I glued two pieces of walnut into the lock mortice-- one at the front of the lock and the other along the top edge, behind the hammer, and re-inlet the new lock plate. After I refinished the entire stock, the patches are hard to spot.

I rust browned the lock and the barrel so they match. I really like the RPL lock. It's a great sparker and it's easy on flints. I was lucky that my pan lined up perfectly with the barrel vent. I've read about others who weren't so lucky. My TC Hawken sat unused for over 20 years, but now with the new lock, I'm enjoying shooting it again.

[Oil Derek]

Good to hear Satwel.  Probably same vintage of rifle and when I fetch it from our guy then I’ll do as Eric mentioned by trying a mock up with the lock bolt in place.