Home Forums Hunting & Shooting Ask The Gunwriters 06/200 @ 2700 question

Dober, I believe it was me that brought up the 2,700/200 thing on the 338-06 thread... here's what I actually said:



Of course I was talking in broad terms... "close" to 2,700 for me would be 2,670 +/-. Others are attached certain speeds so will press on through to achieve them. I'm not one of those. But I have loaded 200's in every 30-06 I've ever owned and it's always surprised me how accurate they generally are. I can't believe I've never bothered to hunt with them. Sheesh.

But I'm perfectly comfortable pouring on a little extra of the slow, single based powder like John mentioned to achieve a velocity just over 2,650... the same 23" rifle ran a 180 just over 2,800, and I see no reason it can't run there.

But I think John just made the case for the 200 grainer's speed far better than I can, so I'll leave it at that.

JB, I'm having trouble seeing the 1/4 rule out of your calculations there. Maybe it's too early and I'm wrong but bringing 58k up to 64k is about 10% increase in pressure and should be up for a 2.5% increase in velocity rather than the 5% you mentioned. No?

Oh, geez..it is too early for that level of math...I can't even count to 21 with my pants on...

I'm not John, but I'll be interested to hear his response. I believe, however, as with all general rules there are exceptions, and the slow, single based H4831, in this particular instance, might be one of those.

1/4 rule works with case capacity and powder weight never with pressure.
The pressure increase exponentialy while the velocity increase only on a semi logarithmic base.
At a certain point of pressure the increase of velocity is almost nil and your rifle become a shell sending pieces of steel everiwhere...

Now that took me a minute to get... jeez!

2.5% will take 2634 to 2700.
edit - wait, my bad! 1/4 rule is for case volume. Time for a nother coffee.

Then what was your original question getting at?

Now I get it!

I started using the 200 grain Nosler Partition because of the good things Phil Shoemaker and Mule Deer reported about it. It has turned into a very versatile load for the things I normally use a 30/06 for.
In the fall when I go to the Little Belts to a hang around with hunting buddies, anything from coyotes to elk and bear can be on the menu, and I have been known to go to Alaska on a whim a couple of times, and that makes a good rifle/load combo to take along.
So far, the only thing I have killed with that load is three antelope, but one was 426 yards and hitting it, even with a lowly 4X scope wasn't a problem.
I am in between 30/06s right now, but when I come into another one, the 200 Grain Nosler Partition will be a load I will use. And if it's going 2625 instead of 2700, I couldn't care less. Also, in the last 30/06 I had, a Tikka, the recoil of the 200 grain loads didn't seem to hurt as much as some of the lighter bullets.

Fred

JB,
That's not what I've been told in the past. A family friend owned a tool and die company in the 60's and 70's, and Remington was his biggest customer. He was a rifle looney, and had the opportunity to go into the Remington ballistics labs--even got to run some of his own pet 7mmRM loads through the pressure barrels.

He showed me my first plots of pressure curves--some of them were from the 60's and hand plotted! He explained to me the subject of pressure spikes/variation (just like you, he made a distinction describing pressure variation between shots) He used the example of differences in max pressure of the 30-06 vs 280 vs 25-06 vs 270. The 30-06 and 280 had higher variation than the 270 and 25-06 according to him., hence the difference in max rated pressures.

This info came from the late 60's through the 70's, has more recent pressure testing revealed new info? Improved powder maybe?

Casey

UncleJesse,

The 1/4 rule has to do with powder capacity in cartridges of the same caliber: Potential velocity changes at 1/4 the rate of any change in powder capacity. But we're talking about the .30-06, so there's no change in powder capacity.

Homer Powley came up with the rule I just mentioned: With single-base powders, velocity increases at half the rate of pressure. So there is no 1/4 involved here.

Another interesting thing abouyt single-based powders is that velocity increases at the same rate as the powder charge. For instance, if we increase the powder charge 2% (about a grain of powder in the old .30-06 load of 50 grains of IMR4895 with a 150-grain bullet) then muzzle velocity increases 2% as well.

This ruel doesn't always hold at the fringes of any powder's usually pressure-range, but if we're working in the "normal" range of pressures it's remarkably accurate.

Hodgdon's data shows two different 200-grain bullets. The max load for the 200 AccuBond is 59.0 H4831 at 2586 fps and 49,400 CUP. Max for the 200 Speer is 57.5 H4831 for 2577 fps at 49,400 CUP.

If we increase the pressure to 51,500 CUP (the max listed by Hodgdon for any .270 loads) the increase would be about 4.35%. Divide that in two and we get an increase in velocity of 2.17%, for around 2640 fps.

Since velocity increases at the same rate as the powder charge, this means an increase to 60.8 grains with the AccuBond and 58.75 grains with the Speer--and even then we're still probably going to be under the maximum SAAMI psi pressure for the .270. It's too bad the Hodgdon data isn't in psi, rather than CUP, since psi data tends to be a little more accurate.

My Hodgdon No.26 gives an unknown 200 grainer 2,690 with H4831 from a 26" bbl. for 49,000 CUP.

I assume the 30-06, in a strong, modern action can run 53,000 CUP?

Casey,

That long ago, the Remington pressures were probably being shot on copper-crusher equipment. It can be accurate enough, if used correctly, but sure doesn't provide the same sort of data as piezo equipment.

All of the ballistics lab folks I've talked to say the .30-06 is really predictable, and that the reason for the lower pressure standard is older rifles, especially low-number Springfields and 1895 Winchesters.

I've also never heard anything about the .280 being more squirrely than the .270, and there's no reason it should be. The 60,000 psi standard for the .280 was because Remington originally developed it for their pump and semi-auto rifles, and they wanted to make sure it didn't cause any problems. The .280 AI's SAAMI standard is 65,000 psi.

Yes, I should've mentioned the copper crusher plug pressure barrels--I realize the peizo barrels are more accurate and measure in psi.

But if what you're saying is true, LOOKOUT--my 30-06AI is about to become a 300 Wthby Lite!........

Now, what's to say the 270 can't fudge a few thousand psi over 65k psi?

Casey

Oh no, its too early for popcorn.

But it's not too early for diet dew and OJ along with some peppered jerky...

Dober

Thanks M D for putting this in print ONE MORE TIME.

This is such OLD NEWS, I don't see why it hasn't become common knowledge. Maybe reloaders don't read. Maybe some can't understand.

I WISH reloading manuals would make TWO lists; one for OLD guns and one for newer manuf. and list some date to distinguish between them.

Thanks Again

Casey,

Laughin'!

But a few years ago I decided to test the old handloading pressure signs, including case-head expansion, and worked up loads for three rifles. One was a .270, and I worked up to 58.5 grains of Reloder 19 with a 130-grain bullet (can't remember exactly which bullet now), no problem. Took them to the Western Powders lab and they averaged 68,000+ psi.

Well heck, 68K is a fire form load for some on the Fire...

Dober