pushing bergers hard SAFELY

rdsii64

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Dec 11, 2008
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452
Location
Jacksonville NC
This past weekend I started working on how fast I can push a 175 grain bullet safely with my current setup. In VERY SMALL increments (read 1/10th grain) I have worked my way up to 44.6 grains of VV N150 . At this time I see no loose primers or primer flow, and the bolt opens and closes smoothly with no excess effort required. Since my loading press uses a floating shell plate I don't have shell holders to see if the fired case will slide into it without undue effort. Are there any other over preasure signs I should look for.
The complete load so far is:
VV N150 - 44.6 grns
Primer - Wolf large Rifle
Brass - Winchester Trmmed to 2.008
Bullet - 175 grn berger long range match bullet
COAL - 2.83
Barrel - 24" 12 twist
 
No problem provided:
Cases extract easily/normal bolt lift
No wiping of the case head
No piercing of primers
No shiny marking of case mouths(from hitting chamber end)

If primers are flattening only, pockets will eventually loosen. Not a big deal really.
Sounds like you're ok.
 
I'm running 5 grains over Bergers max load for 180's out of my 7 Rem Mag. Another guy at work who got me started on bergers said he starts his loading at 5 over (I started at max) and some of his are 10gr's over before he see's pressure signs.
 
I can imagine manuals are conservative, and there is strong basis for it.
Afterall, every barrel is a unique animal, and it really is best to exceed moderate loads with a questioning attitude. It's good learning if nothing else.

There are also those(like myself) who lean toward brass life over velocity.
I cull a little over a hundred for each thousand pieces of brass, before investing in preps & fireforming. That is, I rake 850-900 into a trash can -right up front.
I get the very best of the lot with this.
Then, I'm careful to find a 'moderate' load for the accuracy node desired. I really need those ~ 100pieces to last the life of the barrel!
Moderate is 50k-60Kpsi as validated through calibrated QuickLoad files. Go over 60Kpsi, and brass life shortens, no matter the SAAMI max listed for the cartridge, or lack of pressure signs in the short term.
This may be where you're at. And it could be completely fine for you, but still too expensive for me.

To find 'moderate' with your barrel/load, there is only one way I know to work:
I load 30 working up with new(but discarded) brass. Starting low pressure on up, I measure the case near the web(~.2" from casehead). Before long I will see the case grow to a point and stop(baseline), then as I keep going, I watch for .0005" (5/10thou) additional. This is the point of exceeding 60Kpsi(in my experience), and further increments begin to runaway with atleast a couple pressure signs, all the way to beating the bolt open and finding loose pockets. If you reach that with new brass, you've probably gone to 70-80Kpsi.

Anyway, MY MAX, is just prior to the .0005" jump in diameter over baseline.
So far, I've been able to hit good loads near that point, without exceeding it(I guess, because of the barrel lengths I choose per cartridge capacity). And with minimal sizing of this, occasional annealing, I have never wore out a single case in my life. This is why I'm so picky about the brass I'm gonna live with.

Just a different perspective on pressures accepted.
 
I HOPE YOU KNOW. That the presure of any load goes up as the tempatures goes up. If you work up a load to near max. presure now it will blow up your gun come summer. Any load will be safe at tempatures below what it was worked up at, but even mild loads in cold weather can become dangerious in hot weather.
 
Hey, Mikecr- I can't say that I've heard of "wiping the case head." All of the other high-pressure-pucker-factor signs are familiar to me, though. Is this as though gasses are escaping rearward out the flash-hole and around the primer up? If this is the case would this brass need to be trashed due to an expanded primer pocked? Would you mind explaining that one really qauickly?

I am a proficient hand-loader (or believe I am), and I really appreciate the open passing of knowledge regarding safety typically found on this forum.

EH
 
By wiping the casehead, I mean smearing of the headstamp with the boltface(leaving a brass ring on the boltface).
When pockets loosen, some gas can escape around primers, burning a ring into the boltface.
 
That's interesting. Can't say I've ever looked at the boltface of my rifle that carefully, other than to ensure it's clean from oil/grit/grime/etc...

Thanks again

EH
 
By wiping the casehead, I mean smearing of the headstamp with the boltface(leaving a brass ring on the boltface).
When pockets loosen, some gas can escape around primers, burning a ring into the boltface.

I liked your approach to working up your load. I've done similar with good results. I would also caution the thread starter to not only beware of higher ambient temps when working with borderline loads but also leaving a round in a hot chamber for very long before firing. This can really cause problems......Rich
 
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