Ejected Brass

I have been shooting a fairly new to me, Springfield Armory 1911. It has a heavy recoil spring, advertised as 17#, but feels significantly heavier. The pistol functions well, but today, when I inspected the fired brass, I noticed an indention mark left on the rim of the cases. I used a felt tip marker to make the area stand out. My questions are 1. What is causing this mark? 2. Is it something to be concerned about?

My guess is the boltface on slide has a large machine mark. It's leaving the mark on the case when it's fired. I would guess if you chambered a round and then hand ejected it that it won't have the mark in it. Bolt face can be stoned/polished.
Jon

I think Jon is right.
I had a Ruger SR1911 that did the same thing, there was a step in the bolt face that was left after it was machined. 

Kurt

Jon is correct !   I bought a 45 ACP Range Officer and it did the same thing to the brass. I took a small tool makers file and removed the material off the bolt face opposite the extrator.

Thanks. Yes, you all are right. The mark on the case was fairly deep, so I thought I'd have noticed the "ledge" on the bolt face (opposite from the extractor) before. It was easy to see when I saw it with magnification (these old eyes aren't what they used to be). I've been slowly removing the "step". Although, I wish that they had caught it at the factory. Probably just cosmetic, but it bugged me.

It should be fixed,  it will force your cartridge off center of bore axis.
Jon

and it damages the brass rim ( bends case rim ) at least it did on one I had take hump off of bolt face all is well now.

Deerspy wrote:and it damages the brass rim ( bends case rim ) at least it did on one I had take hump off of bolt face all is well now.

Yes it does, but in this case, not enough to affect reloading.