Regarding that line down the brass - is it being scratched when you are sizing or when the brass is being loaded into/out of the chamber? If it is happening when sizing, you need to inspect your die for foreign debris or otherwise clean it out and/or polish away the speck of whatever imbedded in your die body.
That your brass is going into the chamber roughly and sometimes getting stuck, I'd look at your feed lips and ramp - and polish the sharp edges with a Dremel tool. I do this on all new uppers, regardless. Having the brass get stuck in your chamber - there are a few possibilities that come to mind. You say your brass is once fired. Was that first firing in your chamber? If not, you may need a short-base sizing die as the prior gun could have had a larger chamber than yours. If the brass was first fired in YOUR gun, then I'd look at how you have your sizing die set up, as maybe not sizing all the way to the bottom of the brass - or your sizing button is tweaking your necks or shoulders out of sorts. If your die is set up to where it makes contact with shell holder and you try loading without using the sizing button - and still have an issue, I'd get a short-base sizing die.
Regarding the rifle not extracting, the short-base die might fix the problem entirely, as there is too much friction between brass and chamber on extraction to allow the recoil to push the mainspring back fully. This is called a "short stroke", and assuming your gas block is aligned properly, is usually a result of too light of a powder load. You can either increase the load or purchase a lighter mainspring from Wolff Springs for about $20.00. I'd increase the load, as if the problem persists when you are 3/4+ of the way up the powder charges per manufacturers recommendations, and the problem persists, the lighter spring might not fix the problem.
I'd take a few sized pieces of brass (not charged with powder), and drop them into the chamber, then GENTLY close the bolt to see that the brass will easily allow the bolt to close without force. Then pull charging handle rearward to eject the brass. If it feels as though there is strong resistance to pull the charging handle back - as though something is holding it - that points to a brass problem, possibly the need for short-base die.
If this is a new rifle, pull the bolt carrier assembly out. Push and pull the bolt in and out of the carrier about 150 times to seat the gas rings. it is amazing how much drag on the ejection phase is imparted by new gas rings, especially when using light loads. This can contribute to failure to extract and short stroking - especially with a light load.
There are a lot of other issues that can cause what you are encountering in respect to your handloading practices and your rifle- but these things are pretty common. I think with the scratching and failure to eject, you might have at least a few separate issues going on.
Good luck!
