Advice on selecting a lock for my 1835 Western PA build

[ShutEyeHunter]

I'm building a shootable copy of the family rifle.

Pretty sure it was a late flint converted (badly) to percussion, but I could be talked out of it.

The current lock looks like this one in the TOW catalog:
http://www.trackofthewolf.com/Categories/PartDetail.aspx/763/1/LOCK-GG-BR
except the hammer is a bit crude like this one:
http://www.trackofthewolf.com/Categories/PartDetail.aspx/763/1/LOCK-GA-CR

Lock plate length is 4.75" +/-

(Tried to post a pic, but my browser kept crashing... )

I want to build with both cap and flint, so I need matching locks.

Was thinking that  Late Ketland flint and and the matching percussion conversion would work if I filed the tail of the lock(s) to a smooth curve.

Would appreciate any other ideas / thoughts from the experts.

Details on the rifle I'm copying... (Data is best guess from researching gunsmiths and from the family tree)
Built ~ 1835 by Abe Williams in Washington County PA.  About 50 miles Northeast from the Vincent shop in Marietta, OH.
Fullstock, 36 cal, barrel about 38" 15/16" straight octagon
Double set triggers
Brass furniture with some fairly crude German silver inlays.  One was probably supposed to be an eagle.  I always thought it looked like a penguin.
Current lock is a replacement.  Obviously done by somebody other than a gunsmith.  Front lock screw hole was plugged.  Lock was attached by (gasp) stealing the #10 tang screw, drilling and countersinking the lock plate, and putting a square stove bolt style nut on the sideplate.

Amazingly, it actually fired the last time my Dad & I tried it (1960)

[ShutEyeHunter]

Left this bit out when I re-re-rewrote my post.

There was a useful discussion on locks for Ohio/Vincent rifles here:

http://americanlongrifles.org/forum/index.php?topic=33177.0

I looked up the various recommendations and thought the Ketland was a the best mechanical fit, but would prefer a plainer lock plate.

[FALout]

Without a pic of what your copying, it's hard to suggest what lock to use.  I'm not a fan of having two locks for rifle to switch from cap to flint if that is what you are looking at doing.  Nothing but problems will come with that.  Now if you are looking at building a rifle so it looks like it's been converted from flint to cap, that is a whole different thing that can be achieved.  That lock that you linked to is for use with snail, will not work with most drum if that is what you want to do, you would have to use a large drum for that lock.

[Acer Saccharum]

I agree on the lock switch program is problematic. Build it dedicated one way or the other.

A convertible gun needs a drum and nipple arrangement, which will be trouble once the drum gets screwed in and out a few times. Drum loses its fit, threads become stretched, after a few in and outs, the drum turns beyond its original position, and now do you shoot it with a loose drum?

Warning:
We are in favor of building lots of guns, because you find you can't build just one. Even if you start out with the best of intentions, your house is going to fill up with gun parts.

[Rolf]

Warning:
We are in favor of building lots of guns, because you find you can't build just one. Even if you start out with the best of intentions, your house is going to fill up with gun parts.

Amen to that.

[Bob Roller]

I'm building a shootable copy of the family rifle.

Pretty sure it was a late flint converted (badly) to percussion, but I could be talked out of it.

The current lock looks like this one in the TOW catalog:
http://www.trackofthewolf.com/Categories/PartDetail.aspx/763/1/LOCK-GG-BR
except the hammer is a bit crude like this one:
http://www.trackofthewolf.com/Categories/PartDetail.aspx/763/1/LOCK-GA-CR

Lock plate length is 4.75" +/-

(Tried to post a pic, but my browser kept crashing... )

I want to build with both cap and flint, so I need matching locks.

Was thinking that  Late Ketland flint and and the matching percussion conversion would work if I filed the tail of the lock(s) to a smooth curve.

Would appreciate any other ideas / thoughts from the experts.

Details on the rifle I'm copying... (Data is best guess from researching gunsmiths and from the family tree)
Built ~ 1835 by Abe Williams in Washington County PA.  About 50 miles Northeast from the Vincent shop in Marietta, OH.
Fullstock, 36 cal, barrel about 38" 15/16" straight octagon
Double set triggers
Brass furniture with some fairly crude German silver inlays.  One was probably supposed to be an eagle.  I always thought it looked like a penguin.
Current lock is a replacement.  Obviously done by somebody other than a gunsmith.  Front lock screw hole was plugged.  Lock was attached by (gasp) stealing the #10 tang screw, drilling and countersinking the lock plate, and putting a square stove bolt style nut on the sideplate.

Amazingly, it actually fired the last time my Dad & I tried it (1960)

 Acer is RIGHT. Build the rifle either as a flintlock only or caplock only.
The only alternative would be TWO barrels,one for a flintlock,the other
with a drum and nipple for the caplock.

Bob Roller

[Hungry Horse]

 I think the Chambers lock that is the size of the small Siler, but with the round tailed plate might be a close match. The hammer is much more like what you describe.

                  Hungry Horse

[ShutEyeHunter]

I'm getting a sense that dual ignition is a bad idea

I came up with about 250 potential problems as I was thinking through the build, but I thought hey--they sell pairs of locks....

Two barrels in a pinned stock sounds like an overwhelming PITA and a recipe for splitting the forend--would be easier (as many have pointed out) to make two guns.  I have a TC Hawken that I'd like to convert to flint & PRB.    Patent breech, half stock, and wedge keys should make that easier.  Not going to start that one till I finish the copy, though, so no need to talk me out of that project at this time. ;-)

Taking the unanimous votes from people who know what they're talking about...I'll build the copy as a caplock with a drum to match the current appearance.  Will still be fun to shoot and a great bit of history to leave to the great grandkids.

I'll check out the lock suggestions.  Much easier to match if I only use caplock.

I think I'll stray from the original rifle and not attach the lock with a tang screw and square nut.

Thanks so much for your sound advice (and talking me out of what may have been a disaster)!

[gunmaker]

Any a those "Goulcher" late capper's work fine...you using a drum ?  have enough metal for 4-5 threads into bbl.  Or go with a Chambers late Ketland, a snappy quick one for sure.....Tom

[ShutEyeHunter]

Thanks!  I'll check them out.  If I squint and look through the rust on my lock, the engraving looks like one of the "Goulcher" locks in TOW, etc.  Shape is a good match.

Re: 4-5 threads, I could use a sanity check on my numbers.

I did the calculations (15/16 outside, "X" caliber. 0.016 rifling)

At 18 TPI,
50 cal was 3.6 turns, no good--but 24 TPI would give 4.8
45 cal was 4.1 on the light side--but 24 TPI would give 5.5
40 cal was 4.5 (but 40 cal barrels usually have 0.012 or so rifling, so will be better)

Figured my best choices were 45 or 40, unless the 50 @ 24 TPI is reasonable

Do these pass the sanity check?

[gunmaker]

Go with a fine thd drum 15/16"  .50 with 5 thd should be a go.  .40 cal will be WAY heaver, offhand rifle, not a hunter.  Unless you like a 10 lb. squirrel getter...Just checked a new 5/16"-24  has 5 thd.....Tom

[ShutEyeHunter]

Thanks, I'll go with fine thread and the 50 cal.

The old rifle is 36 cal and with the 38" barrel, it has a remarkably light feel.  Haven't weighed it, I think it's just a balance thing.  "Hangs" on a target better than any rifle I've owned (except maybe the Anschutz free rifle, but that's another story)

Not many squirrels here in Colorado.  Pretty much target shooting and mule deer.  The 50 will be easier to carry up in the mountains for sure and I can use it on mulies out to 50-75 yards with PRB.

[Pete G.]

I think the idea of dual ignition dates back to when most folks didn't really know much about flint and did not believe that flint ignition could be as reliable as it really is. At first it seems like the best of both worlds. It is not.
We have come a long way since then thanks to people like Jim Chambers and Gene Davis, plus a few others thrown in for good luck. Thanks fellas.

[ShutEyeHunter]

Good point re dual ignition and perception of reliability. In this case, i wanted percussion to match the existing historical rifle (for the great grandkids) and the flintlock to for me to shoot while they wait fot it;-)