.22 Matchlock Pistol

[Hetman]

Bit of a silly idea, but any reason why it won't work?

I've been gathering information on matchlocks and I'm confident that I can build a small lock. I still have more than a few questions about everything else though.

I plan on using this barrel as a base. Would a .22 pellet with a patch fit down a rifled .22 barrel? If not, where could I find a smoothbore barrel in such a small caliber?

I've seen .22 muzzleloaders made with bb and pellet gun barrels but I'd rather not go that route. Want it to be neat and done properly.

How would I go about installing a breech plug/tang?
How large should the pan/vent hole be?
How much powder should I use for the primer and main charge?

Here is the stock blank I'm going to buy. I already have basic metalworking tools and the metal for the lock so it's my only other "major" expense. Might pick up 2 in case I mess up the inletting first time around...

 

[Zonie]

IMO, a .22 is a bit small for a patched roundball but I have heard it has been done.

The big problem is fouling. In a larger bore there is enough space for it to escape to as the next shot is rammed. With a .22, there's not a lot of room for it to get out of the way.

Because there needs to be room for a patch a BB (about .177) would work if the patch was thin enough.

You would have to drill and tap some threads for the breech plug.
The minor diameter of the thread should be large enough to create a shoulder where the bore ends and the threads begin.
Any thread 5/16" or larger will leave a shoulder.

In the interest of safety you might want to make the breech plug out of a Grade 8 bolt or set screw. This should be firmly tightened against the shoulder between the minor diameter of the thread and the barrels bore.

The vent is an interesting problem.
It must be large enough to admit the flash from the priming powder but not so large that it will allow too much gas to escape.

With a .50 caliber rifle, the bore has an open area that is 41 times larger than the area of a .078 diameter touch hole.

With a .22 caliber bore, the bore will have an open area that is only 13.4 times larger than the area of a .060 diameter touch hole. This will cause a lot of the powder gas to be blown out of the touch hole rather than propelling the ball.

That makes it almost impossible to predict what sort of prime or powder load will be needed.

As a side note, the alloy of steel that barrel is made from is pretty tough so don't expect it to machine like mild steel.

 

[mooman76]

22 caliber pellets are hollow based like a minie and might work as is. Like Zonie said, fouling will be a major concern. Also as another option if you need slightly smaller the Sheridan air rifle is .20 caliber so they make work better once the barrel is fouled. I'm sure you could find some projectile that would work.

 

[Col. Batguano]

You might think about using the caliber of commonly sized shotgun shot too if you want a round ball. I imagine a 25 pound bag of the stuff will last you a good while!

 

[rafterob]

One of our members has an authentic .22 sidelock. He shoots pellets (unpatched) with something like 7 grains of 3f.

 

[Keb]

I've got a .20 cal & a .25 cal rifle. The .20 is smooth bored & the .25 is rifled. They are not fun or simple to clean because of the small bore size & I rarely shoot them. I'd advise against going through all the trouble of building one that small. It would be less trouble & easier to bore larger holes.

 

[John Taylor]

Many years ago I made an under hammer BB gun with a smooth bore. Had to use the polished BBs as the standard daisy had flat spots and would not shoot strait. No patch was used, bore was a close fit. This was a pistol and a 22 short case was used as a powder measure. I'm thinking it may have had to much powder as it would put a BB through a 1" board at 25 yards. Accuracy was very good for a short barreled smooth bore, it would hit a 100 yard target but not much of a group at that range, 25 yard was about 2"
Most of the old 22 barrels are not very hard, only designed for lead bullets. A grade 5 bolt would be harder than the barrel. A 5/16" fine thread would be fine with at least 5/16" depth of thread. I would think a 5 grain charge of 4F would be plenty. If you want a smooth bore barrel, I get mine from McGowen , You will need to call and tell them what you want, remember a smooth bore barrel will have a .216" or.219" bore for a 22, that's the size before the button is pushed through. You might ask for a 243 barrel which would give a bore of .237". These barrel would be made from 4140 and would be way more strength than you need for black powder.