It’s a 1964 Rem 700 rebarreled and chambered in 280 AI. No oiled chamber. Peterson Brass, 155 gr Absolute Hammer, 60.6 gr of RL16.Depends on the case type.
A belted mag...no.
A rimless case...yes, depending on load.
An oiled chamber can also show this as backthrust is at maximum and may include a stuck bolt.
Need more info, rifle type, cartridge and load.
I’ve always been told that new brass can show a very light ejector swipe, due to extra headspace and not being tight against the boltface, causing it to be forced back on the boltface on ignition.Often, a near max load in NEW cases is fine, shows no flattened primers, ejector swipes or craters...but a once fired case WILL show the above because the case is not expanding to fill the chamber as much and losing energy like a new case does.
Have you chrono’d the load in either brass?
I will guarantee there is a velocity difference.
That’s my game plan now, I’ve got a few boxes of Hornady seconds that I can shoot.Fireform your cases with cup and core bullets touching the lands. This prevents case movement during fireforming. Fireforning like this wll prevent the ejector marks.
Once formed, clean your bore well,then shoot the Absolutes. Absolutes are very slick and offer little resistance.