I wrote this response in another forum referencing a 22LR the same applies for the 22 magnum....just my 2¢.
Using a 22 lr for self defense is like trying to get republicans and Democrats to go out together for a beer and agree on every topic. IT AIN'T GOING TO HAPPEN! Better chance with cats and dogs to drink from the same bowl.
Rimfire calibers like 22 long rifle, or 22 magnum are very lethal calibers. We all know that they can kill and we all know that as a caliber there are a variety of issues that occur when it comes to reliability. From FTF's to FTE's but all the reliability factors can be greatly increased by knowing your capabilities of your firearm and the ballistics of the rimfire cartridge.
Ballistically speaking the problem begins with using standard velocity or subsonic rounds on semi-autos. These rounds may or may not cycle the action, so the solution would be to buy high velocity ammo as these will cycle the action, and by all means avoid bulk ammo because of the duds found in them. Better grade ammo like CCI or Aguila will do great. Using a revolver increases the reliability factor even more than semi auto action because the revolver can fire a greater variety of ammo from standard velocity to sub-sonic to high velocity. If you buy the standard or sub-sonic velocities you can further increase the reliability factor even more now, because you can use premium grade ammo, Like Lapua, Eley, RWS and so on. If you cannot afford premium ammo the revolver still has an advantage in that all you have to do is squeeze the trigger again if you have a dud, try doing that with a semi auto.
I hear about reliability issues with the 22 but who here has not had a reliability issue or read about the issues one has had with their semi auto pistols. How many here have not read about the variety of solutions from cleaning, polishing the ramp, or stove pipes , or send it back to the manufacturer, or use different magazines on centerfire handguns. Guns are mechanical,....they will break. When it comes to a 22 I believe that it is more of a confidence issue at stake than a reliability issue.
There are more pro's than cons when it comes to carrying a 22 lr or 22 magnum vs not carrying one for self defense. There are factors that the shooting sports community as a whole fail to take into consideration when they immediately focus on the negative aspect of the 22 long rifle or magnum round. They fail to realize that the individual may be an elderly person, male or female. They fail to realize that they may have a physical handicap that may limit the use of a larger caliber round, such as arthritis or other debilitating medical conditions. Instead we should inform them of what works in a semi-auto action vs a revolver. Those of you that are young, the day will come where your physical abilities will diminish and can no longer defend yourself physically in hand to hand, or by using a larger caliber revolver.
Lastly, believing that only larger centerfire calibers are better may provide you with a false sense of security thinking that it has "stopping power". In my 37 years of working in a trauma center I saw more deaths from a 22 caliber round than any other caliber and I have witness a small frame woman survive 6 shots from a .357 magnum to the face and head. Seeing this confirms my beliefs, if GOD wills it, the choice of caliber does not matter whether you live or die.
Your 22 magnum revolver is more than adequate for self defense.
I always read about penetration and how it lacks penetration. People also always resort to a gelatin block when it comes to penetration. The truth of the matter is that a slow moving 22 caliber solid round will penetrate just as much as as high velocity hollow point centerfire.
Intrinsically our nature is to respond to a threat using lethal force but not all threats require a central nervous shot to stop the threat. It is about training
" train for what you have." With todays rounds we are light years ahead from 40 years ago.
People forget that archery hunters of days gone by and now bring animals down weighing hundreds of pounds with an arrow, and it really does not have that much muzzle energy. I think of the 22 as a little arrow that can shatter a bone, sever an artery, penetrate and cause a pneumothorax in the lung or stop the heart. Imagine what it will do in the head.