Am I reading my brass correctly?

[shawnba67]

I have just started my load development for my Mauser 98 in 8mm-06AI. I loaded up some necked up 30-06 brass starting at 55gr of. iMR 4350 and going up .5 gr at a time to 60. Did 3 ea. i had some trouble with my chrono at the early part had to move it 6 ft off the muzzle bout half way through. At 59.5 I got what looked like the start of a flattened primer in win brass the Rem brass next to it was same charge. At 60 gr(only went on because all the 60gr loads were in rem brass) I got what looks like ejector marks. The pics are the best I can do at the moment. Am I seeing what I think I'm seeing? First is the flat primer, then ejector mark on the first 0 of 3006 If I'm reading it right then 59 is the stopping point for this rifle. All brass was once fired before.
60gr was 2750fps @6ft from muzzle 200gr bullet

[williamwaco]

Can't see well enough for ejector marks - but you do not have a flat primer.
Those primers are fine.

[shawnba67]

So that shiny spot isn't an ejector mark? It didn't start showing up til the higher end loads. It is about the same width as the ejector slot in the bolt face.

[Tatume]

There is a shiny spot on the right photo at the 12 o'clock position that could be an ejector extrusion rub. If so, then you're in the high-pressure realm. It's time to back off.

[shawnba67]

It looks scraped off. So my brass reading isn't to far off! Thank you much This is my first wildcat and I figured I ought get my thinking double checked before I'm off into the unknown

[tomme boy]

What does the data for a 3006 with a 200 gr bullet say? It should be a little less PSI with the 8mm as there is a larger volume of gas that lets off.

[shawnba67]

54-55 gr of IMr 4350 for reg 30-06.

Ackley gets up to 60. I'm not sure how the act of being fire formed affects the pressure. I hope now that it holds 5% more powder I get a little more oomph before I hit high pressure again. But 2700 fps will do it if I can't get more safely enough.

[jonp]

I don't see a flat primer

[Linstrum]

That is the way you want your primers to look! You don't have any signs of dangerous pressure yet that I can see, but from the amount of powder you are using you are probably getting into that ball park. If you aren't where you want to be yet, at this point I'd slow down and increase charges by 2/10 grain. What you look for are sharp edges around the firing pin indentation edges and out next to the edge of the primer pocket, and you still have nice totally rounded radiused primer edges. But - - - when working up loads you have to leave yourself a nice margin of safety so that on a really hot day or when you store your ammo in the hot trunk of your car, you are still safe from excessive pressure, so don't push things. By the way, I keep my ammo in the coolest place in the car, I never put it where it gets hot, and I don't leave it sitting out in the sun at the range.

rl 1,194

[EDG]

Your primers look fine. I would guess they would take another grain or two.
But I do see that scraped spot. I would no be in too big a hurry to jump the load up. You might check the load that produced the bright spot by shooting 5 more. If you keep seeing that it is time to back off a bit.

However you will need to keep an open mind. I have bought thousands of once fired R-P case from indoor ranges that show the scrape marks with the factory primer and load. 6mm Rem RP brass and .25-06 Rem RP brass even show up with blown primers from time to time because they are loaded so hot at the factory.

I notice that your have both RP and WW brass. You need to pick one or the other for your load development.

If you have a lot of WW brass pick it because it is usually lighter (more internal volume) and it is harder than RP.
However a load worked up in WW brass may not be safe in the softer and heavier RP brass.

If you have mostly R-P brass it will do fine but it might show pressure at slighly lower charge weights.

[littlejack]

Hey Shawn:
As already stated above, the primers are fine. I HAVE seen plenty of partially flattened primers with "factory" loaded ammunition. As for the ejector marks, I have seen plenty of those on factory loaded ammunition also. There are other things that can cause the ejector marks on a case. One is an oily chamber, allowing the case to NOT grip onto the chamber walls when the round fired. Another would softer brass.
You are probably getting close to your goal, but IMHO, I do not believe that your loads are in the dangerously high pressure
area.
Regards
Jack

[UNIQUEDOT]

Look through a few loading manuals or try searching online for photos of flat primers. You will see the difference between a flat primer and yours which are fine.

[EDG]

Oil in a chamber does not increase pressure inside the case.
When brass is mashed back into an ejector slot it is because the brass is yielding.
Some ejector slots are sharp and so are the ejector holes on M700 Remingtons.
The symptoms you get from high pressure are NOT 100% consistent.

1. You can slowly expand primer pockets with loads that do not show a bright extractor slot.
2. I have blown primers in a 7.65 Mauser using very hard USGI brass. There was NO bright spot.
However there was a rectangle that matched the slot (not bright though). The headstamp was mashed so flat that you could almost not read the SL-54 headstamp. The cases extracted normally even though smoke blew out of the action.

[littlejack]

EDG:
I did not say that "Oil in the chamber increases pressure inside the case."
Maybe you should read my post again.
The oily chamber causes the case to (slip) be slammed against the bolt face, causing the brass to be extruded into the ejector port.
As opposed to a DRY chamber that will hold the case when fired, and helping stop the case from being slammed into the bolt face as violently, and extruding brass into the ejector port.
Just clarifying.
Jack

[Shiloh]

I have just started my load development for my Mauser 98 in 8mm-06AI. I loaded up some necked up 30-06 brass starting at 55gr of. iMR 4350 and going up .5 gr at a time to 60. Did 3 ea. i had some trouble with my chrono at the early part had to move it 6 ft off the muzzle bout half way through. At 59.5 I got what looked like the start of a flattened primer in win brass the Rem brass next to it was same charge. At 60 gr(only went on because all the 60gr loads were in rem brass) I got what looks like ejector marks. The pics are the best I can do at the moment. Am I seeing what I think I'm seeing? First is the flat primer, then ejector mark on the first 0 of 3006 If I'm reading it right then 59 is the stopping point for this rifle. All brass was once fired before.
60gr was 2750fps @6ft from muzzle 200gr bullet

Those primers show no flattening at all. There is still a radius on the edges. Flattened primers are FLAT.

Shiloh

[Motor]

Reading primers is not a good way to determine pressure. Yes it was kind of the only thing we had before chronagraphs but it really is not reliable.

I've seen factory loaded ammo come out of rifles with primers so flat that there was no gap between primer and case left. I've also had primers that looked OK but my velocity was over max and the bolt was a little hard to open which is a sure sign of too much pressure.

With your 8mm-06, I'd be looking at all the data I could find and comparing notes. 2700f/s with a 200gr bullet is pretty impressive.

I don't know how you get good readings with your chronagraph only 6 feet from the muzzle. Most need to be at least 10 feet.

[John Boy]

Add one more, having seen all types of spent primers ... look good to me
Can't say much for the off center firing pin though

[Tonto]

Top left primer starting to look flatter to me, just slightly at the resolution I can see, always err on the side of caution and wear shooting glasses......

[nemesisenforcer]

That might be an ejector mark, but that in and of itself doesn't necessarily mean that pressure is excessive. Like everyone said the primers are fine and that is the first sign to look for.

Do they extract hard? Bright ring on case head? These are things to look for, of course with an AI design, brass stretching is minimal so that might not be a reliable indicator.

[Wayne Smith]

Everything I have read - extensive - says that there are NO reliable and repeatable pressure signs on brass. There are simply too many variables in the equasion to accomplish that. Stick to your velocity figures and trust them. If you are getting expanded primer pockets, stretch marks on your brass or primers extruding into the firing pin hole you are way over pressure.