The
9mm Luger round (9x19mm) was designed by Luger for our Luger pistols.
It's specification is a standard. The bullet shape has been re-designed many times, but the case specification is stable at this point (last changed in 2007). (SAAMI maintains
manufacturing standards for ammo in the USA). An index of their specs for pistol cartridges is
here.
That said, I reload 9mm, and have encountered quite a bit of small variance between manufacturers. The size difference you may be observing is the taper crimp some manufacturers use to snug in the cartridge case around the bullet.
These things cannot account for the surface you're seeing on your spent cartridges. They look like there has been corrosion damage (or something else) that made the middle of your chamber rough. You should be able to inspect this visually, and by feel (using the tip of a chop stick rubbed against the side).
This area is rather precision in it's dimensions. When a cartridge is fired, the brass is compressed against the chamber walls with 40,000+psi of pressure. Being brass, it springs back a little, allowing extraction. A rough surface, or an uneven surface that is letting high pressure gas blow back are both possibilities.
The 9mm pistol cartridge head spaces on the front edge of the case. There could also be damage to this area of the chamber that is permitting blowback. It's possible that too much head space is leaving a gap for gasses to blow through.
The chamber needs to be inspected for damage, headspace and fit.
