Ever so faint ejector mark

[wade2big]

I always load conservatively and probably always will. It’s probably why I’ve never owned a 6.5cm that pushes a 140 at 2800 or a 308 that pushes a 175 at the same speed. Moving on.

Do you guys consider a faint ejector mark as a sign of pressure? I mean so slight that you have to get the angle right with the light to just barely see it? I’m not talking a swipe or an indention. Just an ever so slight shadow without any primer crater or anything of that nature.

 

[Kadams1563]

Wait there’s something wrong with a CM pushing a 140 at 2800? Hell there’s still room in the case at those speeds lol.

Of your loading very conservative it’s probably something else besides pressure causing the swipe. I look for multiple pressure signs before I start worrying.

 

[NH4X]

Wade, you talkin gas or bolt ? If bolt ....running mid load, I'd do a little looking ,make sure no carbon ring is present . Gas ,running mid loads, .....not really . FPS " should" be higher than normal if pressure is high.

 

[wade2big]

I’m not having any problems. As soon as I even think I see a mark, I backoff. I may be too conservative which is why I’m asking.

 

[NH4X]

My rule of thumb in bolt action....if I'm shooting same length barrel as book load data , fps" should " be fairly close to book, if my barrel is longer than book ,which they usually are,I expect fps to be higher . The bolt I shoot the most has a fixed ejector , so I go off fps and hard bolt.lift to tell me when enough is too much. Gas , I don't run AGBs and usually find a load about 1gr less than Hodgdon annual manual max and see some
faint ejector marks ...sometimes on the first firing of.new brass.

 

[357Max]

Wait there’s something wrong with a CM pushing a 140 at 2800?

Yes! To slow, unless it's a Tika Hell factory Berger 140hyb loads run 2850 & Lost Munitions 140Hyb is 2930.

The one on the left is a touch warm for ref. & it was 150fps slower than my top loads with same bullet. That was a little Valk experiment with TS 15.5 that didn't go so well. Kidding obviously, but speed doesn't always correlate to pressure. I'm surprised the primer stayed in that one.
The 6.5 on the right was a 156 Vulcan at 2838 from a 25" barrel

Goes to show how much powder selection matters.

@wade2big - I think your to conservative.

Seriously though AR's tend to leave swipes. Tells you more about gas system than pressure.
Indentations from the ejector do indicate pressure. If head space is over .006 in a AR like most factory 5.56 77gr & 308 FGMM 168's, the brass is ugly cause it gets a running start at the bolt.

If you want a better answer then post the load data & gun data. Everything matters.

 

[wade2big]

My rule of thumb in bolt action....if I'm shooting same length barrel as book load data , fps" should " be fairly close to book, if my barrel is longer than book ,which they usually are,I expect fps to be higher . The bolt I shoot the most has a fixed ejector , so I go off fps and hard bolt.lift to tell me when enough is too much. Gas , I don't run AGBs and usually find a load about 1gr less than Hodgdon annual manual max and see some
faint ejector marks ...sometimes on the first firing of.new brass.

I thought a hard bolt lift was from brass flowing into the ejector and extractor openings in the bolt (smears). Does the hard bolt lift come from the extractor flow in a mechanical ejector bolt? Do you get a swipe there when you have a hard bolt lift?

 

[wade2big]

Yes! To slow, unless it's a Tika Hell factory Berger 140hyb loads run 2850 & Lost Munitions 140Hyb is 2930.

The one on the left is a touch warm for ref. & it was 150fps slower than my top loads with same bullet. That was a little Valk experiment with TS 15.5 that didn't go so well. Kidding obviously, but speed doesn't always correlate to pressure. I'm surprised the primer stayed in that one.
The 6.5 on the right was a 156 Vulcan at 2838 from a 25" barrel
View attachment 8068000
Goes to show how much powder selection matters.

@wade2big - I think your to conservative.

Seriously though AR's tend to leave swipes. Tells you more about gas system than pressure.
Indentations from the ejector do indicate pressure. If head space is over .006 in a AR like most factory 5.56 77gr & 308 FGMM 168's, the brass is ugly cause it gets a running start at the bolt.

If you want a better answer then post the load data & gun data. Everything matters.

I don’t have a load that is in question. Everyone kind of filled in their own blanks. . My only question was if a stand alone ever so faint ejector mark is a sign of pressure. I’m talking barely noticeable in the right lighting. In a bolt gun.

 

[Potsy]

I’m sure it’s a sign of pressure. Bullets exiting the muzzle are a sign of pressure.
I’ve seen plenty of faint ejector marks on factory ammo.
My AR will do it and so will my ABolt.
I get faint ones with my Origin .22BR at the ejector slot, and I don’t consider my loads for it hot at all.
Anymore I just run stuff over the chrono to make sure it’s reasonable and party on.

 

[357Max]

I don’t have a load that is in question. Everyone kind of filled in their own blanks. . My only question was if a stand alone ever so faint ejector mark is a sign of pressure. I’m talking barely noticeable in the right lighting. In a bolt gun.

To that I would say no it's not.

 

[wade2big]

To that I would say no it's not.

Then I have been a bit too conservative like you said. Definitely no 156gr at 2850fps over here.

 

[secondofangle2]

Everybody wants a Rosetta Stone...

 

[NH4X]

Do you get a swipe there when you have a hard bolt lift?

No swipe with hard bolt lift . Thinking back and wondering at the time it happened , if the hard bolt lift was because I didn't set shoulder back any ,although I ran it through a FL sizing die . load was .5 gr. over max and I was using coated bullets ,I really didn't expect to have that . I've ran over max with different bullet with no hard bolt lift .

Edit: This is a sloppy Ruger M77 Hawkeye action ,that I rebarreled ,pillar / glass bedded ........shoots damn good for what it is.

 

[357Max]

I thought a hard bolt lift was from brass flowing into the ejector and extractor openings in the bolt (smears). Does the hard bolt lift come from the extractor flow in a mechanical ejector bolt? Do you get a swipe there when you have a hard bolt lift?

To this question the answer is..........it depends. It could be a die problem or improperly set head space on the ammo. The action design also plays a big role. The picture I posted above of the 6.5 Creedmoor was shot in an ARC Nucleus. That action doesn't have a round spring loaded ejector, instead it has a mechanical thin blade ejector (never leaves a mark). If you look real close at the pic you'll see a light circular swipe between the LA & the primer. Feeling it when opening the bolt is almost imperceptible. I have to pay real close attention when opening to feel it. The brass grew enough to be just barely pinned against the bolt after firing. That tells me pressure is up there near top end. I also look at the radius on the edge of the primer & that depends on the primer used. That particular Vulcan load used a FGM205 primer & had I used a cci#41 there would be more radius.

Shit I don't think it can really be explained well enough to soak in. You really just have to pay attention, know what to look for, & then do it....... a lot.

Guns are like cars. They have personalities. A Buick Le saber isn't capable of cornering like like a Corvette. With the right tire selection on the Le saber & a poor choice on the Vette they might get close (powder selection). Both however, are fucked on ice (powder over charged).

Like I said before everything matters. Brass, primers, dies, action, etc.

 

[spife7980]

I thought a hard bolt lift was from brass flowing into the ejector and extractor openings in the bolt (smears). Does the hard bolt lift come from the extractor flow in a mechanical ejector bolt? Do you get a swipe there when you have a hard bolt lift?

Hard lift can also comefrom the case body being swelled up in the chamber which is my primary indicator. But ejector marks aren’t a good sign unless it’s crap soft brass. Big marks are a back off now sign.

 

[hafejd30]

 

[Rocketmandb]

I always load conservatively and probably always will. It’s probably why I’ve never owned a 6.5cm that pushes a 140 at 2800 or a 308 that pushes a 175 at the same speed. Moving on.

Do you guys consider a faint ejector mark as a sign of pressure? I mean so slight that you have to get the angle right with the light to just barely see it? I’m not talking a swipe or an indention. Just an ever so slight shadow without any primer crater or anything of that nature.

Ejector marks are not always a sign of pressure. A heavy spring can cause the same.

EDIT: To clarify - swipe marks are not always a sign of pressure. If you're getting indentions, that's a different story.

 

[bax]

I always load conservatively and probably always will. It’s probably why I’ve never owned a 6.5cm that pushes a 140 at 2800 or a 308 that pushes a 175 at the same speed. Moving on.

Do you guys consider a faint ejector mark as a sign of pressure? I mean so slight that you have to get the angle right with the light to just barely see it? I’m not talking a swipe or an indention. Just an ever so slight shadow without any primer crater or anything of that nature.

As far as I know, there are two reasons for an ejector mark - pressure and burrs around the ejector hole. In the case of pressure, there is enough pressure inside the case to force the case base into the ejector hole. Due to high pressure the case is expanded in both radius and length so friction prevents it from rotating when you open the bolt. So, when you open the bolt, you shear off that tiny bit of brass extruded into the ejector hole - and voila! a shiny mark. More pressure, more mark.

In the case of burrs, standard pressure is enough to force the brass into the burrs and then leave a scrub as you open the bolt. I think you said that it was not an expensive weapon, maybe it has left-over burrs from the machining process. Press your finger against the ejector hole and wiggle it around. Did you bleed? If yes, do something to get rid of the burrs.

 

[hafejd30]

Keep in mind brass fired it’s first time can cause these in mild loads. I learned that when loading for a buddies 6.5. It left ejector marks on even the lowest book recommendation. With zero other signs. I think the factory soft brass coupled with the initial expansion to fit the chamber when firing may contribute to that.

His first rounds with 143 ELDX were in the 2500’s for fps with these marks. In my opinion that wasn’t even an option to stop for over pressure when the gun is designed for hunting. I was loading and shooting and made the call to continue on ignoring those marks. They never went away and 2.5 gr later I started seeing the primers start to flatten a touch and ran into heavier bolt lift. Obviously I stopped there