There are two sides to reliability... mechanical, and primer ignition.
I.E. Failure to feed/extract/eject, and failure to fire.
As far as mechanical reliability...
I find that combinations of poor case crimp which leads to loose bullets that wobble and spin in the case... soft lead... and sometimes bullet shape... those tend to be the biggest causes of jams/malfunctions.
Bulk pack ammo tends to be most guilty of poor crimps and soft lead.
I have never seen premium 22lr ammo that had poor case crimping. The lead hardness can vary depending on the bullets intended purpose... But most high velocity rounds use harder lead. And even the softer lead rounds work better due to proper case crimp.
Lead round nose or plated round nose feeds the most reliably in general.
And failures to eject are often just random unlucky, (as in not caused by anything other than random chance) or due to a dirty gun or a low powered round which slows down the action and leads to weak ejection force. Bulk ammo tends to be dirty and inconsistent in power.
Now the other side to reliability... primer ignition
Poor distribution of priming compound evenly around the rim of the case leads to occasional failures to fire. A second strike may fire the round, but not guaranteed... Often reloading the round may be required to get a fresh part of the rim to be struck by the firing pin in order to fire... Dud rounds that refuse to fire at all are pretty rare.
Once again, bulk pack ammo tends to be the biggest culprit of this type of problem.
I have never had a premium rimfire round not fire on the first attempt.
I would bet that the instances of a premium rimfire round needing a second strike are about the same as centerfire rounds, (ignoring steel cased hard primer rounds) and straight up duds even more unlikely.
There is a third type of malfunction with rimfires... but I left it out from above because it is almost always user error/caused.
Unlike a centerfire, which can fire when slightly out of battery. (though not very good to do) The rimfire needs the case rim to contact the barrel fully in order for the firing pin to impart enough force to actually ignite the primer. So being even a little out of battery will cause a failure to fire.
This type of malfunction is almost always cause by a dirty gun. Either poor maintenance, or it can start to happen at the end of a long day at the range after firing a few hundred rounds. (maybe less if the gun is a tight gun, like target pistols can be)
Also failures to extract tend to be from dirty extractors... so another user caused issue.
The take away from all that...
Bulk ammo can be finicky, some guns will not like it very much, or may only like certain brands of bulk.
Premium ammo is probably close to centerfire ammo in reliability to ignite the primer. It also tends to function very well in the gun.
Modern semiautos should function with bulk pack ammo... or if not all, at least one or two brands of bulk.
Modern semiautos should run pretty much any premium ammo just fine, but you may find a brand/style that your gun does not like.
If you have a gun that will not fire ANY type of bulk... you may have an issue, call the manufacturer.
If you have a gun that does not like to feed several different types/brands of premium 22lr ammo, and you can only find one that works... you most likely have a lemon. (combined with not feeding any type of bulk and its pretty much a given) The only exception to this is if you have a highly tuned/custom target gun.
Last edited by marine6680; September 5, 2012 at 06:13 AM.