I thought that is why God made suppressors.
Over gassing does not cause extraction issues unless extraction is marginal to begin with. With the right spring and extractor, the rim will be torn off before the extractor will jump it.
The original extractor springs used in the M4 gave problems because the spring rate wasn't up to the job of the more violent extraction and wore out faster when compared to use in a rifle. As a stopgap, o-rings were used to beef up the spring rate. Colt developed a new spring, the copper colored spring, with a stiffer spring rate. It's supposed to be used without the donut.
When an AR starts developing extraction problems, it's not because it's over gassed (although it may in fact be over gassed), it's because either the spring starting to sack, the extractor is wearing or both. Slowing down the carrier with a heavier buffer or by cutting down on the gas may allow the extractor to work reliably once more, but it's only postponing the inevitable. It's only a matter of time until the worn parts will need to be replaced
How do the fired cases look now?
Probably easier to upload a pic than describe it.
Remington: On the case neck it looks like they are scratched up a bit halfway down the neck. Case mouths do not have flat areas.
Fiocchi: No real scratches on the neck but the case mouths have a flat spot and just below the flat spot are 2 small dings (about the size of a tip of a nail maybe smaller).
Both cases have that ring around the neck right where it meets the shoulder.
http://i.imgur.com/dmzU9wI.jpg?1
The flat spot is not uncommon with the 300.
The shorter 300 case rotates faster and can hit the deflector mouth first.
That ring at the neck-shoulder junction still looks a little funny.
There may possibly be a chamber issue.
Yeah with the brass my only concern is that ring. In an all time idiot move I was distracted/not paying attention and the bolt slammed on a NO GO gauge. I had the headspace double checked and a NO GO gauge still would not chamber so I thought I was good to go. But maybe it pushed up a small burr/ring right at the top of the neck in the chamber. Trying to think if I should get it to a smith and have it looked at with a borescope to see or just get a new barrel. They are on sale right now for like $175. Not sure how much a smith would charge to check the bore. I like the barrel from an accuracy standpoint. Granted I have only shot it at 25 yards with iron sights but it stacks my shots right on top of each other.
I have sent the barrel back to Ballistic Advantage for them to look at. I had a local gunsmith take a quick look. They said based on the brass it is probably a chamber issue. He said it looks like it may just need a light touch with a finish reamer. However they don't have any 300 blk reamers and that it would be best for me to send the barrel back. I will update again once I here back from them.
The plot thickens...BA got my barrel and bolt today. Clint said he ran the hell out of the barrel with my bolt and 4 others in the shop. No issues. No marks on the brass like I was getting. Maybe it just happened to be the 2 types of ammo I was using??? Who knows. He is sending me a new barrel anyway.
Thanks to BA and Clint for their great customer service. I did not expect a same day turnaround...or a new barrel if they did not find anything wrong. I will update this post when I run the new barrel...hopefully early next week.