On 2015-08-28, wrote:
As anyone who shoots knows, it has become pretty hard to get .22 ammo.
Especially CB shorts and longs. And then when you do find some it is
of limited amount and exorbitant cost. So as I was trying to fall
asleep after waking from a hot flash in the middle of the night it
occurred to me that I could make my own .22 centerfire brass, cast my
own bullets, and use off the shelf primers. Checking yesterday for
primer availability I found several sellers with small pistol primers
in stock at less than $30.00 per 1000. That's less than 3 cents per
primer, about what I used to pay before this ammo buying panic and
subsequent gouging started. This morning I examined the bolt on my
Remington model 514 and determined it would be pretty easy to make a
new bolt for centerfire ammo. And most of the parts from the existing
could be used in the new one.

My S&W .22 Jet will fire either centerfire .22 Jet cartridges
(.357 magnum necked down to .22) *or* .22 rimfire, either with a
swap-out of cylinder or with adaptor sleeves in the standard .22 Jet
cylinder. It does this with a pair of firing pins, and a switchable
striker in the hammer, so no modification needed there.

The mods to a Ruger .22 target would be fairly simple, but you
would want to set up a catcher for the brass so you *could* reload it
before someone stepped on it.

I would need to machine cases from solid
brass, but I have a lathe with a bar feed setup that could make them
really fast. Each case would require two operations so I could run the
second operation while the lathe was doing the first operation. I have
never really reloaded ammo before though I did reload a few rounds 45
years ago when a friend's dad showed me how his reloading setup
worked. He let me load a few rounds but I may as well have never done
it before because it was so long ago. But from reading about it online
it appears that spent brass cases can usually be used 4 or 5 times,
and some times even more depending on how light or heavy the load is.

Even a .22 LR would be very light by comparison with the .22
Jet, and would probably get something like 20 or more reloads. Consider
just how lightweight the .22 rimfire cartridges are. The case comes
back as a cylinder, bulges out and folds back in to make the back,
providing a crushable space for the rimfire primer compound to lurk in
and be triggered by the firing pin.

I have lots of pure lead and making a mold would be pretty easy. But
would a machined case be as durable as a formed case?

Far more durable than a .22 rimfire case, I would expect.

And since the
smallest primers I can find are .175" O.D. and .22 brass is .224" O.D.
there would only be a .0245 wall thickness between the primer and the
case outside.

Consider that while the OD of the primer is 0.175", the case
needs to reduce the through hole diameter to something quite a bit
smaller to support the anvil built into the primer.

Then again, since the case is trapped in the chamber
maybe that's not a problem.

The thickness of the base required to properly support the
primer should make something a lot stronger than the .22 rimfire case,
so I would not worry -- even with smokeless up to a full .22 LR load,
and you are going to be a lot milder.

And I would be using black powder or
black powder substitute, not smokeless powder, since my aim is to make
low power quiet ammo for target practice. I have a small revolver and
two rifles that I could convert to centerfire without too much work.
So, am I nut to consider this?

An interesting project.

Normal cartridges (except for the rimfire ones) are normally
made by cutting out a disc of brass, then deep drawing the walls while
the base is clamped in position until you get a cylindrical shape, then
the normal sizing operations for tapered cases. And the rim is turned
as necessary, and the primer pocket swaged (harder than if machined from
the brass. There are certainly a number of annealing steps during the
forming, of course. But for the strength loads you are planning,
machined cases will certainly be strong enough.

Shoot enough, and you will want an automatic screw machine to
produce them. :-)

Good Luck,
DoN.

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