Your thoughts, .22 to .22mag

Llance

Llance

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I have two k frame .22's and I'm thinking of converting one of them to .22 mag.

Does anyone have thoughts about such a conversion? I would have to have a machinist do the work as I don't have a mill, and my bench mounted drill press is not fine enough to do the reaming.

Would it be better to just get a .22mag cylinder to fit?
 
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You're probably better off just buying a gun chambered for the .22 MRF (Model 48).

I'm going off the top of my head, but .22 LR barrels have a .222" bore. .22 MRF barrels are .224". When gunmakers offer guns with dual cylinders, they use a barrel designed for the .22 MRF cartridge.

I'm sure people have done it, but I wouldn't recommend shooting .22 MRF's through a barrel designed for Long Rifle cartridges.
 
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I suspect you'd want a different barrel twist as well for the increased velocity, if you wanted accuracy that is.
 
Hearty Agreement

outta_ammo said:
Unfortunately, it's not just the cylinder. The bore dimensions are also different. IIRC the standard .22 bore is around .216 while the magnum needs more like .223.

I would be looking for a M48 or M51 instead.
Click to expand...

Please don't cut up or irreversibly alter a .22 S&W. If you were considering buying a M48 or M51 you would prefer an original, un-altered.
 
s&wchad said:
You're probably better off just buying a gun chambered for the .22 MRF (Model 48).

I'm going off the top of my head, but .22 LR barrels have a .222" bore. .22 MRF barrels are .224". When gunmakers offer guns with dual cylinders, they use a barrel designed for the .22 MRF cartridge.

I'm sure people have done it, but I wouldn't recommend shooting .22 MRF's through a barrel designed for Long Rifle cartridges.
Click to expand...
Can anyone confirm that the M48/53 actually has a different bore diameter and rate of twist? For some reason, I'm skeptical. Yes, they should be, but are they?
 
When Ruger did the Singel-Six Convertable that came with both .22LR and .22Mag cylinders they compromised on a bore diameter of .119. This causes some loss of acuracy when shooting .22LR. I keep the magnum cylinder in mine.
 
I have one. Shoots just fine, all I do is switch out cylinders. I did not do it, bought it that way so I don't know exactly what was done.
 
Just like armorer951, I did his conversion to a Pre-18. Works like a champ. If you don't mind the semi/sorta pinto look. Cylinder with extractor from Gun Parts Corp for about $80 plus some other parts. Shoots really well.

Stu
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This question comes up on the forum at least once a year. There are people like me who believe what the manufacturers and ammunition manufacturers say (don't do it), and who really like their fingers as they are.

But it has been done since the .22 magnum was created, and a nearly equal number of people who've either done it, or think it's fine.

People are going to do what they want, and that's okay with me. As long as they don't injure anyone else, and are willing to accept any consequences, instead of blaming the gun and ammo makers, the gunsmith, etc.
 
I have a Ruger single six with the interchangeable 22 mag cylinder.
I shot 22 mags once. Right now I am not sure where the mag cylinder is. The 22 LR shoots fine and I do not see any real advantage to the 22 mag in a handgun. I would not mess up a nice SW for the conversion. What wold you have when you were done?
 
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When you say machinist, mill and drill press it really sounds expensive with no room for error. Take the advice you have received and just buy a cylinder and get a gunsmith to time the ratchets with your existing cylinder. That takes care of the cylinder but a 22 mag has a .224 bullet and a .22 LR has a .222 bullet. The barrel groove and diameter differences may or may not mesh well with your conversion. Ruger apparently splits the difference in their single six dual cylinder gun barrels and S&W frequently provided or made available two cylinder guns in the past. I installed a 22 LR barrel in a model 48 one time and it was very time consuming. The owner said the grouping was acceptable.
 
Its easy. You can rent a reamer and just make the cylinder a .22 Mag. The bore diameter isn't worth worrying about.

I did it not long ago with this Model 63. All is well many hundreds of rounds later. It wouldn't eject .22 LR rounds without a mallet. Works great with .22 Mags.

Total cost - 40 bucks.
 

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With today's gun-smithing prices, wait times and parts prices - hardly worth the effort! Simply buy what you want and sell the ones you don't.

Before buying a 22 magnum, check into availability and prices of.22 mag. ammo. That might change your mind.
 
A .224 bullet will become a .222 bullet the instant it passes through the forcing cone with very little if any extra pressure. A K22 cylinder is the same size as a model 19 357 cylinder and I have made several 327 federal cylinders from K22 cylinders.

a 22 mag has about 24,000psi and a 357 around 35,000. I don't care how you heat treat a 357 cylinder there is no way a wall as thin as a model 19 357 cylinder is weaker than any K22 cylinder anyway.

Over sized bullets in under sized barrels are NOT the cause of blown up guns. Over sized bullets that can not release from the case because they are trapped tightly by the chamber neck are.

Anyone who has sized bullets knows that it doesn't make much to make a 360 bullet a 357-8 The handle on my sizer isn't 12" long. Takes way more force to size brass.

As I have stated before P. O. Ackley fired .358 bullets through .308 barrels repeatedly by simply using 35 Whelen chambers in them. With NO excess pressures.

Plus, lots of guys here fire .454 and larger bullets down .452 barrels regularly with 45 colts that have large throats. That is a lot more bullet to squeeze down than any .224 bullet and the chamber walls on a 45 colt are way way way thinner.

I could/would make a 22 mag cylinder for any of my K22 if I thought the cylinder and effort was worth it. First even 200fps from a 40 gr bullet isn't that much for the cost and noise. But a guy over at the Highroad shot a convertable revolver over a chronograph. The results. The 22 magnum out of a 4 inch taurus revolver clocked 1250-1300 fps. The 22 LR 36 gr stinger's clocked 1260-1350 . Whoopppeee doo

Plus, my 22Jet, 22 Harvey Kay Chuck and my 22TCM revolvers and my 221 XP100 all leave any 22 mag in the dust and I can reload them.
 
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I know of at least one custom gunsmith who told me he uses the standard Ruger Blackhawk .30Carbine barrel (.308") when he converts one to the old .32-20 cartridge (.311-.313"). He also told me that it doesn't matter whether the owner shoots lead or jacketed thru his conversions... and yes, he leaves the .308" barrel as is (.308').
Apparently, we may 'worry' over nothing at times....

J.
 
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One of the most mind-bending stories I've read (here) was about someone in days gone trying a 45ACP round in a 30-06 (IIRC). Said it made a " long, skinny bullet" when fired. Not something I'd be comfortable trying!
 
Now firing say a 180 gr 312 bullet loaded in a 30-06 case in a standard 30-06 can be a problem. BUT NOT because of the bore. When the bolt cams that oversized bullet into the chamber the .312 bullet is clamped very tightly in the neck of the case because the chamber was made to fit a .308 bullet held in a case. When fired the bullet is difficult to move and the pressure builds and may exceed the actions strength before it releases. But, if the bullet is allowed to move it quickly sizes down.

Another bad combination is when the bullet nose holds enough headspace even though the case does not fit the chamber. Lots of bad things can start happening when the brass comes apart and releases gas pressure flow in directions other than down the bore. BAD BAD
 
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