AZ Shooter
Member
REPORT: .22 rimfire conversion of SIG P226 9mm. The first 500 rounds.
I want to begin this report with some comments on the .22 rimfire cartridge. When I shot competitively in the U.S. Air Force, I referred to this cartridge as the “.22 whim-fire”. My reason was that if one was going to have a malfunction during a shot string in a match, it would most likely occur with the .22.
I also discovered that certain pistols had less malfunctions than others. I settled on a High Standard Supermatic Trophy. For me at least, I had fewer alibi calls with this pistol than with either the Ruger Mark 1 or the Smith and Wesson Model 41.
The design of the cartridge itself is its biggest downfall. I see two main reasons for this. The first is the way the cartridge is primed. With the priming compound implanted inside the rim, even something as simple as dropping a box could break sections of the priming compound loose; and Murphy’s Law clearly states that it will be that exact section that is under your firing pin when you attempt to shoot that cartridge! I imagine modern ammunition is better made than the older types and is probably more durable. Then again, it may just seem that way because less bad stuff would have befallen newer ammo than older ammo. Still, the inherent unreliability of the rimfire design, I believe, was the major reason for the push for centerfire designs. I read of an archaeological exploration of the Custer battlefield done in the 1980’s. A number of intact .44 Henry rimfire rounds were found. Many of them had been struck multiple times by a firing pin. Some had been struck multiple times by more than one firing pin! The Indian warriors apparently passed the misfires around in the hopes they might work in someone else’s rifle! So we are back to the “whim fire” concept.
The second problem I have noticed with rimfire ammunition is in the way the bullet is held in the case. This would not be a problem for revolver shooters, but for a semiautomatic that must feed from a magazine, then run up a ramp into a chamber, it is another story altogether.
In centerfire ammunition, almost all of the bullet is inside the cartridge case. It is held firmly and tightly. The rimfire design is different. When one examines a .22 cartridge, one notices that most of the bullet is sticking out in front of the case; less than half is inside. What this means in relation to feeding in a semiautomatic weapon is that the bullet is easily pushed out of alignment with the case! You can make the bullet wobble in the case like a child’s tooth that is about to fall out. This can cause feeding problems if the bullet is loose enough that when it contacts the feed ramp, it angles in the case and will not chamber. I consider this to be an ammunition malfunction rather than a firearm problem because if the bullet is held tightly in the case as it should be, it will feed just fine.
The instructions that came with the .22 conversion stated that high velocity ammunition was required. It seems that all the modern high velocity .22 ammunition produced nowadays is copper or brass plated. This is an advantage in a semiauto because lead is soft and it is “sticky”. By that I mean because it deforms so easily, it sticks to feed ramps and the tip can deform to the point where it won’t go up the ramp.
All of the ammunition I have expended for this 500 round report was OLD ammunition! Consider this box as an example: it is dated 1927 but it may be newer than that, but the box design changed in the 1950’s so there is no getting around the fact that the ammunition from this box was at least 50 years old and maybe older!
My shop is in a large retirement community and this is the kind and vintage of much of the ammunition I see coming in the door. Much of the .22 high velocity ammunition from that era is plain lead; not plated.
Okay, now on to the report.
FAILURE TO FEED
Ten examples.
4………”bent bullet syndrome”. The bullet was not tight in the case.
3……….unplated bullets that stuck on the feed ramp.
2……….failure due to the previous round not fully operating the slide. Perhaps bad ammunition or more likely standard velocity rounds.
1……….reason for failure not recognizable.
MISFIRE
Two examples.
STOVEPIPE
Two examples. Stovepipes, unless the extractor or ejector are broken, are operator induced malfunctions.
What does this all mean?
Taking the total of 14 problems, the malfunction rate would be 2.8%.
If we remove the obvious operator problems and misfires the rate would be 2%.
If we remove the less obvious ammunition problems (loose bullets, low velocity, unplated bullets), the failure rate would be .02 %
I can live with that! In my opinion the conversion unit is a total success. It operates smoothly and with minimal problems. It shoots accurately and allows practice on a base platform that is (literally) identical with the 9mm version of the pistol. If I had used modern plated high velocity ammunition most of the problems would not have happened. If I can get this kind of performance out of a whim fire, I am totally satisfied!
I want to begin this report with some comments on the .22 rimfire cartridge. When I shot competitively in the U.S. Air Force, I referred to this cartridge as the “.22 whim-fire”. My reason was that if one was going to have a malfunction during a shot string in a match, it would most likely occur with the .22.
I also discovered that certain pistols had less malfunctions than others. I settled on a High Standard Supermatic Trophy. For me at least, I had fewer alibi calls with this pistol than with either the Ruger Mark 1 or the Smith and Wesson Model 41.
The design of the cartridge itself is its biggest downfall. I see two main reasons for this. The first is the way the cartridge is primed. With the priming compound implanted inside the rim, even something as simple as dropping a box could break sections of the priming compound loose; and Murphy’s Law clearly states that it will be that exact section that is under your firing pin when you attempt to shoot that cartridge! I imagine modern ammunition is better made than the older types and is probably more durable. Then again, it may just seem that way because less bad stuff would have befallen newer ammo than older ammo. Still, the inherent unreliability of the rimfire design, I believe, was the major reason for the push for centerfire designs. I read of an archaeological exploration of the Custer battlefield done in the 1980’s. A number of intact .44 Henry rimfire rounds were found. Many of them had been struck multiple times by a firing pin. Some had been struck multiple times by more than one firing pin! The Indian warriors apparently passed the misfires around in the hopes they might work in someone else’s rifle! So we are back to the “whim fire” concept.
The second problem I have noticed with rimfire ammunition is in the way the bullet is held in the case. This would not be a problem for revolver shooters, but for a semiautomatic that must feed from a magazine, then run up a ramp into a chamber, it is another story altogether.
In centerfire ammunition, almost all of the bullet is inside the cartridge case. It is held firmly and tightly. The rimfire design is different. When one examines a .22 cartridge, one notices that most of the bullet is sticking out in front of the case; less than half is inside. What this means in relation to feeding in a semiautomatic weapon is that the bullet is easily pushed out of alignment with the case! You can make the bullet wobble in the case like a child’s tooth that is about to fall out. This can cause feeding problems if the bullet is loose enough that when it contacts the feed ramp, it angles in the case and will not chamber. I consider this to be an ammunition malfunction rather than a firearm problem because if the bullet is held tightly in the case as it should be, it will feed just fine.
The instructions that came with the .22 conversion stated that high velocity ammunition was required. It seems that all the modern high velocity .22 ammunition produced nowadays is copper or brass plated. This is an advantage in a semiauto because lead is soft and it is “sticky”. By that I mean because it deforms so easily, it sticks to feed ramps and the tip can deform to the point where it won’t go up the ramp.
All of the ammunition I have expended for this 500 round report was OLD ammunition! Consider this box as an example: it is dated 1927 but it may be newer than that, but the box design changed in the 1950’s so there is no getting around the fact that the ammunition from this box was at least 50 years old and maybe older!
My shop is in a large retirement community and this is the kind and vintage of much of the ammunition I see coming in the door. Much of the .22 high velocity ammunition from that era is plain lead; not plated.
Okay, now on to the report.
FAILURE TO FEED
Ten examples.
4………”bent bullet syndrome”. The bullet was not tight in the case.
3……….unplated bullets that stuck on the feed ramp.
2……….failure due to the previous round not fully operating the slide. Perhaps bad ammunition or more likely standard velocity rounds.
1……….reason for failure not recognizable.
MISFIRE
Two examples.
STOVEPIPE
Two examples. Stovepipes, unless the extractor or ejector are broken, are operator induced malfunctions.
What does this all mean?
Taking the total of 14 problems, the malfunction rate would be 2.8%.
If we remove the obvious operator problems and misfires the rate would be 2%.
If we remove the less obvious ammunition problems (loose bullets, low velocity, unplated bullets), the failure rate would be .02 %
I can live with that! In my opinion the conversion unit is a total success. It operates smoothly and with minimal problems. It shoots accurately and allows practice on a base platform that is (literally) identical with the 9mm version of the pistol. If I had used modern plated high velocity ammunition most of the problems would not have happened. If I can get this kind of performance out of a whim fire, I am totally satisfied!
