45 acp vs 45 auto

[modrifle3]

OK ... I know this is the same caliber. So please don't tell me.

My pondering is why Ruger seems to use this barrel stamping with no real consistency. I have a p90 stamped 45 auto made before my p97 marked 45 acp and two other p90s marked both ways. Is it political? Marketing? Trying to make the old seem new?

Anyone else wonder this or do I need another project.....

 

[cjs1945]

My P90 and P97 say 45 ACP but P345 and SR1911 say 45 Auto. My P91 and P944 say 40 Auto but SR40 and SR40c say 40 S&W. I thought they didn't want S&W or Colt name on their products was the reason for Auto, but on my newer 45 pistols they went to Auto and on newer 40 cal. they went to S&W. The reasoning for it might always be unclear.

 

[graygun]

IDK but it's an interesting observation seeing the way "semi auto" is used in/by the media nowadays;etching "auto" onto a gun would really make it look sinister to the misinformed and some others.