building a convertible?

[Len Graves]

I have been requested to build a flint/percussion. Have any of you builders built a convertible? If so, are there any particular things which would make this a tricky build. I kind of know lock placement will be tricky. Any thing else? The rifle will be a Lancaster with Siler locks. Thanks.

 

[horsetrader]

I had a "convertible". Building wise it seems the best approach is to built in percussion so the drum fits the lock plate. Hoever buy switching for and back from drum to venthole there is a big chance to wear out the thread.....

 

[rich pierce]

It's not that hard with Siler locks. I'd do the percussion first and use Jim Chambers "converted" lockplate that still has the fence remnant, etc. The drum/percussion lockplate absolutely needs more precise fit.

I think most folks find it a cute idea but a pain in the butt in the end to change locks, barrels and take out the drum and put in a vent. Eventually the drum will tighten back up too far and the nipple won't line up with the cock anymore. wait a minute, that didn't sound right. :rotf: I meant the nipple won't line up with the HAMMER anymore. That's better. Then you'll have to shim the drum, blah blah, blah.

I did make one percussion gun with 3 barrels and even that was a pain. I have a .50 rifled, .54 rifled, and .62 smooth barrel for it. My old hunting buddy used to rib me something awful about carrying a "quiver of barrels" and telling the squirrels, "Wait just a minute there, you little varmint! I'll have the shot barrel on this gun in a second!"

 

[Zonie]

Install the percussion lock first and locate the drum for it. That location will work just fine for the vent for the flintlock.

Other than that, a little messing with the sear release arm might be needed to get the trigger pull to be the same with both locks but this isn't a real big issue.

I built this Bedford using L&R Percussion and Flintlocks.

One of my very early builds was this Reading which uses the same Siler combinition you are talking about.

 

[Len Graves]

I kinda thought the build would be as you suggest. Also thought about going percussion first, but needed an opinion someone else for added push. I also mentioned to the future owner about the problems of "change over". I then mentioned I would seek advice from this forum. He is still mulling it over in his head. If he sees your convertible I am sure he would want one like that ( sweet). do you have any change in point of impact from flint to cap? Thanks for your replies all you guys.

 

[hotsparks]

Just finishing a .45 smooth rifle with Davis Late Ketland flint/percussion locks. Rich and Zonie are right, build it with the percussion so the nipple will align with the notch in the lockplate. The flint is a tad more forgiving about touchhole placement, but unless the percussion lockplate supports the nipple, there's gonna be trouble. Good luck.
John

 

[rich pierce]

Real nice rifles, Zonie!
I think my comments about the possible problems down the road are probably reflecting my bias for just shooting a flintlock. I started out shooting percussion rifles but sure prefer fiddling with flintlocks. But I can see advantages for having both.

One option I would consider is to have 2 locks and 2 barrels. Then there would be a lot less fiddling, removing the drum, vent, etc. More expensive.

 

[Len Graves]

I am partial to flinters too. When confronted with the prospect of building this gun I thought why not? I have never done one, so it might be fun. I do agree that some of the problems might over come the advantages. I will relay those problems and opinions to the prospective owner and let him decide. Another barrel? More money? Who cares someone else is buying the parts. Seriously that is another option to consider. Thanks again guys.

 

[SR James]

I have one convertible, a fullstock plains rifle that I purchased already built as a flinter. After mulling over my options, I went with an extra barrel and percussion lock. With its hooked breech, changing barrels was just as fast as exchanging a vent liner/drum with none of the possible disadvantages thereof. Plus, separate sights for each ignition system. And it also gives you the option of changing calibers. More expensive,yes, but it's worked well for me.

 

[Zonie]

With the Flintlock installed, it needs somewhere around 5 grains of powder added to the load to hit the same point of aim.

With either lock it is an accurate rifle.

Those two holes that missed the bird were compliments of the idiot on the next bench and his "spray and pray" method of shooting his AK.
That explains the little specs too. They were from dirt that was thrown up into my target.

 

[Len Graves]

Don't you just love those shooters that think our guns are of secondary importance because they fire bullets one at a time? I had a fellow at a public range shoot my target "because there are only four holes in Yours and mine is riddled". You have some beautiful guns there. Five grain difference isn't too bad a compensation for point of impact. Well I am waiting for some of the furniture to arrive. In the mean time I will inform my friend of the pros and cons of a change over gun. I try to keep you folks informed. I am working on a .40 Lancaster between shoots. After all idle hands Etc. Thanks again for the imput.

 

[Ray-Vigo]

Sorry if I'm a bit late-- but this got me curious as to the Siler: what is the process for swapping the drum over to the vent liner? Is it as simple as removing the drum and then just screwing in a liner for the touch hole? Or is there something more to it like tapping in new threads etc? I've seen a few people talk about convertible Siler guns and it got me curious.

 

[Zonie]

Yes, it is as simple as unscrewing the drum or the vent liner and installing the opposite style and swapping out the locks.

Because the drum can take a beating (even though it is supported by the lock plate) it must have larger threads than say, a vent liner that is going to be installed in a Flintlock only gun.
This means the size of the threaded hole for the drum must be fairly large.
If the flat width on the barrel is larger than 3/8 inch a 3/8-24 thread will work. On the smaller barrels one is forced to use the 5/16-24 size. Fortunatly the vent liner for flintlocks are available in these same sizes (the White Lightning being the exception).

Although the locks are both made from the same lockplate castings, casting variation does make them somewhat different.
Although these differences are small, when you inlet the lockplates you must decide whether to modify the steel shape and size of the larger plate to match the smaller one or you must cut the wood away to allow the largest plate to fit and live with the small gaps between the wood and the smaller plate. This isn't a "biggie" but it must be dealt with.

Another thing that comes up is the height location of the sear arm in the locks.
That is, when one lock is at full cock the height of the sear arm should be close to the same as the sear arm on the other lock.

Although I've built 2 Convertible's (Bedford and Reading style), I don't know that I would build another one.
Usually a shooter will have their heart set on either one or the other and would not be interested in swapping back and forth between locks.

Hope this answered your question.

 

[Ray-Vigo]

Interesting-- does this compromise the quality of ignition of these guns in the sense that it can do both, but neither well? Could this method be reliably used to convert a gun from one system to another simply by using the "convertible" feature and then never switching back? Or does it yield an inferior ignition?

 

[4deer]

Just a thought how about putting the drum on the lock itself not the barrel so that when you put on the caplock the flash hole liner stays in? Or would this possibly give blow back right into the shooters face?

 

[Ray-Vigo]

Also, what color finish do the Siler locks come usually? Is it grey, black, brown etc? I'm seeing pictures of locks online that have different colorings, but I'm not sure which is truly the stock color. It seems coloring the lock would be difficult.

 

[Zonie]

simonthecat: Just my opinion but I think that if the percussion drum were attached to the lockplate and positioned to align with the vent liner in the side of the barrel, the gap between the drum and the vent liner would cause the vented flames from the powder to blow down into the lock area and burn the H out of the stocks wood.

This method would in a sense, trap the gas in that region causing a great deal of force that would try to blow the lock off of the gun.
For example, if a 1/2 inch diameter drum were used its area would be .196 square inches. If the exiting gas were at a pressure of 3000 psi (which is less than the internal breech pressure), the force on the lockplate would be about 600 pounds! This ignores the fact that there is additional area of the lockplate that would be pushed against by the gasses.
Even if the drum were tight against the side of the barrel, that pressure would force it away allowing the gasses to escape in all directions.

Ray-Vigo : Siler locks, as they come from the factory are a matt wax cast finish of a gray, steel color.
Many builders use fine wet/dry sandpaper to remove the matt finish and then either polish the surfaces and leave them in the white or brown them or blue them depending on what they want to end up with.
The locks on my Bedford (in the photo above) were sanded and then browned with Birchwood Casey Plum Brown.
If the matt finish is left on the lockplate it will be a dull gray. If the matt finish is then browned it will be very dark brown or blackish in appearance.

 

[Ray-Vigo]

I see, wish I could get a pre-finished Siler in a dark color blue, black or brown or the like then. I'm particularly interested in the concept of a simple swap without having to disassemble and re-finish the lock.

 

[4deer]

simonthecat: Just my opinion but I think that if the percussion drum were attached to the lockplate and positioned to align with the vent liner in the side of the barrel, the gap between the drum and the vent liner would cause the vented flames from the powder to blow down into the lock area and burn the H out of the stocks wood.

This method would in a sense, trap the gas in that region causing a great deal of force that would try to blow the lock off of the gun.
For example, if a 1/2 inch diameter drum were used its area would be .196 square inches. If the exiting gas were at a pressure of 3000 psi (which is less than the internal breech pressure), the force on the lockplate would be about 600 pounds! This ignores the fact that there is additional area of the lockplate that would be pushed against by the gasses.
Even if the drum were tight against the side of the barrel, that pressure would force it away allowing the gasses to escape in all directions.

Good point. :surrender:

 

[Ray-Vigo]

The large Siler standard 1/2 inch drum is a 5/16- 24 thread for a .50 cal?

I've been looking for the threading information in the specs, but haven't found anything.