30-06 load flattened primers?

Hi guys,

*edit* can't seem to post pictures, but considering the absence of other pressure signs, what's your opinion?

I think I found my albatross in load development. I've been on a mission to find a flat shooting, hard hitting 30-06 load for a few years now. My local store had Hodgdon Superformance on sale for $49 a pound and I was intrigued by the velocities that it had for my rifle with heavier weight bullets so I bought a bunch on a whim.

I started working up a load with that powder, Starline brass, Federal 210 primers and 178 gn ELD-X projectiles.

Early testing was encouraging. Was getting great velocities as I approached the upper limit of the load charts. I found my accuracy node near the upper end (not surprising since all research says that that powder loves a full case). With a 59.6 gn load I'm averaging 2904 FPS (approaching 300 win mag territory!) with an ES of 11 and an SD of 5. I'm also getting sub MOA results on 3 shot groups to 100, 200 and 300 with results between .755 and .813 MOA.

Now to the question, I'm .3 gn above the suggested max load and safely worked up from 2.2 gns under. No obvious signs of pressure, easy bolt lift etc. However, upon examining the cases in artificial light I think that the primers might be a little flat - even when well under max load. The one on the left is at 2.2 gns under, the one at the right is .3 gns over. What's your opinion on the safety (and the results) of this load work up?

With photos

Primers are definitely flat. You're very close to pressure signs, as long as you worked this load up during the warm temperatures it will be fine during hunting season.

With photos

338 dude said:

Primers are definitely flat. You're very close to pressure signs, as long as you worked this load up during the warm temperatures it will be fine during hunting season.

Click to expand...

That's what I was thinking. Just wanted to defer to folks with more experience. Started load development in 80° and finished at 57° which would be the upper end of my hunting temps anyway. I shoot a lower velocity, cheaper bullet for practice in the summer anyway.

The case on the left seems to have the flatter primer in my opinion although the firing pin indentation looks deeper on the right. I would not be concerned if all primers looked like the one on the right if there are no other signs of pressure.

What make of brass are you using?

Have you tried Hodgdon 4831 SC?

Using Starline brass. Haven't tried that powder, but heard good things. Ball powder is messy. But I live in a very remote northern location and have to take what I can get

If you are using Virginia brass,the primer could be backing out ,then the case moves back slamming the primer back in and flattening. I've had flattened primers fireforming brass.

I'm not thing you to ignore pressure signs,just that flat pri.ers alone doesn't always mean pressure.

Pockets didn't offer much resistance to get primers into, so this makes sense.

"Safety" is always a personal issue. However, a few things to consider.

1) Primers are the weakest point
2) SAAMI spec for the 30-06 is 60,000 PSI
3) Assuming your using a non-milsurp rifle consider the following:

• 270 win max SAAMI is 65,000 PSI, 25-06 is 63,000 PSI, 280 AI 65,000
• All of the above are mfg from the same basic brass
• The rifle and brass manufactures do not say "Oh, this Rem 700, Win Mod 70, or Tikka T3 action (or brass) going down the line is going to be for a 30-06 so we let's make it weaker"
• Nor do barrel manufactures say this 30 cal barrel will be in a 30-06 and not a 300 Win Mag so we can make it weaker.

The net 30-06 load data has a sort of "built in safety margin".

I personally would not be concerned.

med358-boise said:

"Safety" is always a personal issue. However, a few things to consider.

1) Primers are the weakest point
2) SAAMI spec for the 30-06 is 60,000 PSI
3) Assuming your using a non-milsurp rifle consider the following:

• 270 win max SAAMI is 65,000 PSI, 25-06 is 63,000 PSI, 280 AI 65,000
• All of the above are mfg from the same basic brass
• The rifle and brass manufactures do not say "Oh, this Rem 700, Win Mod 70, or Tikka T3 action (or brass) going down the line is going to be for a 30-06 so we let's make it weaker"
• Nor do barrel manufactures say this 30 cal barrel will be in a 30-06 and not a 300 Win Mag so we can make it weaker.

The net 30-06 load data has a sort of "built in safety margin".

I personally would not be concerned.

Click to expand...

Great response! It's a modern Savage 110 with stainless barrel and action, so I'm sure it can tolerate a bit above 60,000psi. I'd like to run it through Quickload, but my version is so old it doesn't have that powder or projectile.

I would not lose any sleep over primers that look like that given there are no other pressure signs. The primers aren't even showing any cratering and they haven't completely filled the pocket either. Unless you are getting loose pockets I would not worry. As little as 3 thou extra headspace will flatten primers.

Have you measured expansion just above the web. That and harder bolt lift means a lot more to me when judging pressure than primer condition or even ejector marks.

Superperformance has Never been in QL.

Footsie80 said:

approaching 300 win mag territory

Click to expand...

Hmmmmm, I don't think so….
178g bullets will surpass 3200fps in a properly throated 300WM.
Next step for your load will be loose primer pockets, no way would I be running that load more than once.

Cheers.

Critter Picker said:

If you are using Virginia brass,the primer could be backing out ,then the case moves back slamming the primer back in and flattening. I've had flattened primers fireforming brass.

I'm not thing you to ignore pressure signs,just that flat pri.ers alone doesn't always mean pressure.

Click to expand...

Critter Picker is spot on with his question: Is the brass you are shooting "virgin" as in never shot before? Nevermind the spellcheck Virginia error. Though its kinda cute!

I did not see that question answered. His explanation is perfect too.

Flat primers are always suspect as far as pressure signs for me. I tend to start low -- have gotten flat primers for years with new brass at moderate pressures. Always worried till I grasped the above.

And -- with moderate loads or if you are FL resizing, the flattened primers can persist. So long as the case first moves forward with the firing pin, then fires and initially fireforms to the chamber, then pushing the primer back, and then stretching the case head back, you will then get flat primers.