TargetTalk

I can't find any ammo that will chamber in it. I have tried CCI Green Tab, CCI Pistol Match and Winchester Target. None will chamber completely. I brushed the chamber to insure there was no fouling buildup, and I cleaned betwen the breech face and extractor to insure the extractor seated completely. Is this pistol set up for some specific type of ammunition, or do I have some other problem?

What model Hammerli?

How many rounds are thru the pistol? My Hammerli 208s will start to form a ring in the chamber after 100rds or so. That ring of carbon fouling will slowly build and inhibit feeding and extraction.

Did you SCRUB the chamber with the brush? Use a 6.5mm brush and bore cleaner and thoroughly scrub the chamber.

Is it chambered for 22lr or 22 short?

Some pistols (although typically not semi-autos) have a very short "leade" (the region between where the case ends and the rifling begins). That's so the bullets are actually engaging the rifling a bit when seated. Even when things are spotless, if you just drop a round into the chamber, they won't go in all the way. It's common in free pistols.

That said, I'm betting a dirty chamber. It's possible it's a .22 short barrel, but I would expect it would come with magazines that wouldn't even allow loading .22 long rifle cartridges.