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View Full Version : 22 wmr semi's and update on short barreled variants


jackandblood
03-11-2011, 9:43 AM
As I understand it, the chief problem of semi-auto .22 wmr is the nature of the case design, which lacks the bottleneck that aids extraction for standard rifle cartridges (and likely for the .17hmr). The case has too high of a straight-case length to bullet length and diameter ratio.

If my understanding is correct, then wouldn't a decent solution be to do like Aguila super heavy 22lrs? Make the bullet longer and shorten the case by maybe 1.5-2mm. Less velocity, more weight, and a shorter (but still much longer than .lr) case that hopefully would extract more reliably. If bullet weight vs. standard rifling comes into play, make a bullet a JHP filled with above norm amounts of polymer to create a spitzer shape. Probably can get it back down to 40 gr. , less velocity, but more reliable extraction and perhaps a denser and larger quantity of polymer to aid penetration.

Also. The two prime candidates for good .22 wmr performance out of short barrels are Hornady's 22 mag 45gr. These aren't expected to be readily available for ~3 months.

Speer makes a Gold Dot .22 wmr, 40 gr. 1000-1150 fps out of 2" NAA revolver. Probably would do excellent out of a Ruger or Heritagemfg longer barreled .22wmr. - These are waaaay backordered (I called speer). Any retailer that will carry them regularly is backordered at least a month. You can try requesting a retailer to try to get some in, but likely the effort will mean much higher than MSRP prices.

bussda
03-11-2011, 9:36 PM
As I understand it, the chief problem of semi-auto .22 wmr is the nature of the case design, which lacks the bottleneck that aids extraction for standard rifle cartridges (and likely for the .17hmr). The case has too high of a straight-case length to bullet length and diameter ratio.


Not entirely. The .22WMR also has a slower burning powder. And significantly higher chamber pressures. More time is required to allow the case to contract back to it's original size. This requires the action of extracting the case to be delayed. Just like the KelTec PMR-30 does.