There's one out there. Several years back I had the chance to shoot a bolt action 45 ACP rifle. Barrel length between 16 and 18 inches, bolt action, used a stripper clip for 3 shot max capacity, barrel was threaded for silencer, very compact gun. I was told it was a short range sniper rifle. At a short distance of 25 yards all shots shot through the same hole with only a slight clover leaf to identify they actually went through the same hole. My partner was spotting with a scope and swore I missed every shot after the first shot. It wasn't until we walked to the target that we found out how accurate the gun was.
I found your question and this forum because I'm trying to find that same mft/model gun now. I'll re-post a reply if I find one.