30-06 load flattened primers?

[Footsie80]

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?

 

[Footsie80]

With photos

 

[338 dude]

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.

 

[Footsie80]

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.

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.

 

[PddPdd]

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?

 

[Footsie80]

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

 

[Critter Picker]

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.

 

[Footsie80]

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

 

[med358-boise]

"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.