ADG Brass Ejector Marks

[jlphillips1]

I loaded up some virgin ADG brass with 245 Bergers with H1000 for my 300 PRC. There is no published load data that I could find, so I started at 72 grains and worked my way up to 77 grains in 0.5 grain increments. Everything was loaded 0.030 off the lands in a Bergara HMR premier.

Everything shot 1/4-1/2 moa and I noticed some ejector marks at 77 grain, so I stopped and went back inside. Absolutely no change in bolt lift, no cratered primers and no extra recoil. Calm, 58 degrees, cloudy and 1250 elevation.

When I went back inside, I looked at my brass in better light and I found faint ejector marks on all of the brass all the way back to 72 grains.

Is ADG brass softer and are faint ejector normal? As I said before, no other signs of pressure. Thoughts?

 

[Shane Lindsey]

Take an empty case (virgin) and chamber it. When you remove it, do you see swipe/ smiley marks. If you do, it may be tight in the chamber. I get this with virgin cases and ADG in a RUM.

Could be a few things. Rough ejector pin, pin hole was not beveled. I had the bolt face cleaned up and it seemed to fix the issue. Still see it lightly, but it lets me know I am at pressure and I back it down a touch. There is a thread that talks about bolt face issues by @orkin that may shed some light on this.

 

[Monteria]

I don't know what action you are shooting, or if this is the only barrel you have had on it, but some actions leave an ejector mark on everything.

I have a Howa 1500 on its second barrel and it has marked nearly every load in every brass since day 1.

Incidentally, it is now a 300PRC and I am shooting ADG brass.

Steve

 

[jlphillips1]

Thanks for the reply. I shot some factory Hornady rounds in it and I didn't see any ejector marks, but that is the only other brass I've tried. I also reloaded that same Hornady brass and never saw any ejector marks until I was approaching max load with 220 grain eldx and H1000.

 

[Shane Lindsey]

Do you see them on a virgin unfired case/round?

 

[jlphillips1]

Not on the Hornady brass, but it was all factory ammo when it was virgin. I did see it on virgin ADG brass.

 

[ThrdKllr]

Check the virgin brass against the fired brass. Measure case head to the datum on the shoulder. If the virgin brass is shorter you may be getting some case head movement when it stretches and fire forms to the chamber. With a shorter case it moves forward until it contacts the shoulder and then the case head is blown back against the bolt. I have a 7mmRM that does it with factory ammo but doesn't do it on properly resized fired brass.

 

[Shane Lindsey]

Thicker necks on ADG???

 

[jlphillips1]

Check the virgin brass against the fired brass. Measure case head to the datum on the shoulder. If the virgin brass is shorter you may be getting some case head movement when it stretches and fire forms to the chamber. With a shorter case it moves forward until it contacts the shoulder and then the case head is blown back against the bolt. I have a 7mmRM that does it with factory ammo but doesn't do it on properly resized fired brass.

I measured the virgin brass against the fired brass and they were 0.0005 different. I would say they were the same length.

 

[jlphillips1]

Do you see them on a virgin unfired case/round?

No

 

[jlphillips1]

Take an empty case (virgin) and chamber it. When you remove it, do you see swipe/ smiley marks. If you do, it may be tight in the chamber. I get this with virgin cases and ADG in a RUM.

Could be a few things. Rough ejector pin, pin hole was not beveled. I had the bolt face cleaned up and it seemed to fix the issue. Still see it lightly, but it lets me know I am at pressure and I back it down a touch. There is a thread that talks about bolt face issues by @orkin that may shed some light on this.

I do see the smiley face on the virgin ADG brass, but not on the virgin Hornady brass.