Ejector mark on Brass

[jackinfl]

My son and I shot yesterday. He shoots 168 FGMM Factory ammo and I shoot my reloaded 168 AMAX.
It rained on us. Guns got wet, ammo got wet.

I noticed several pieces of brass had round marks on the back of the case near the rim. looking at the bolt face this looks like the Remington ejector.

His gun is Factory mine has been worked by GAP.

What are these makes caused by?

 

[ChadTRG42]

Re: Ejector mark on Brass

The ejector marks are caused by excessive pressure. When ammo or the chamber area of a rifle gets wet and a round is fired, the moisture in there causes an increase in pressure. It has to do with water trying to be compressed. Keep the ammo and chamber area dry and you'll be ok. We have seen this problem in shooting matches when guys run a max load. When their ammo gets wet, their hot load is now excessively hot, and causing all kinds of problems.

 

[buffybuster]

Re: Ejector mark on Brass

If it happens only with wet ammo/wet chamber, it's not so much excessive pressure but increased bolt thrust. The water acts as a barrier/lubricant, not allowing the brass case expand and grip the chamber walls. That results in increased thrust from the casehead onto the boltface.

 

[jackinfl]

Re: Ejector mark on Brass

Chad,
Thanks! Is this brass OK to reloaded?

 

[Tripwire]

Re: Ejector mark on Brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: buffybuster</div><div class="ubbcode-body">If it happens only with wet ammo/wet chamber, it's not so much excessive pressure but increased bolt thrust. The water acts as a barrier/lubricant, not allowing the brass case expand and grip the chamber walls. That results in increased thrust from the casehead onto the boltface. </div></div>

I second that.....

 

[Tripwire]

Re: Ejector mark on Brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jackinfl</div><div class="ubbcode-body">Chad,
Thanks! Is this brass OK to reloaded? </div></div>

Well how bad are the ejector marks?

Pronounced, or do you gotta hold 'em in the light just right to see 'em?

Find out if your primer pockets are loose or not; and if you want, measure the pressure ring compared to a known case fired "dry". If the pressure ring is bigger then the brass is likely bad.

What you've done is the same exact thing that leaving case lube on the case will do, or leaving oil in the chamber.

If the primer pockets are still tight, and nothing else is out of the ordinary, then a slight ejector mark can be removed with the careful use of a small fine toothed file.

Or, you could just shoot 'em......