Well, the holes are there to delay blowback, if you were specifically wondering about the holes. I haven't ever owned or shot one of these guns so I don't know nuts really, but I have handled one before and seen the chamber holes. People who have owned them seem to tend towards saying nothing about them was real great, except muzzle flash.
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Do note that part for these guns may be hard to come by!
I have seen internet posts of others looking for parts, and not being able to find any.
I found this site looking now:
http://www.automagparts.com/
but this seems to be just parts for the .44-caliber pistol.
AMT closed and was bought, and that company also closed and was bought again. I cannot find the link, but last I saw (a few months ago) the place that had the remaining parts stock only had a few parts for some of the rifles and a couple models of the pistols, and the 22WMR pistol was
not one of them.
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If you are wanting such a pistol in that caliber,
Accu-Tek/Excel Arms has a autopistol in 17HMR/22WMR, not out yet but soon they say.
copy of a print ad here:
http://www.norcom2000.com/users/dcimper/assorted/avrunketl/hooba/accellerator.html
company website:
http://www.excelarms.com
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