If you have to have a wildcat, make it very little taper, sharp shoulder and super short neck. You'll get some gains that way. Depending on what type of rifle you have it may be easier to just punch it out to 300 mag. For serious performance gains over the 06 you need a 338.
What about the 30-06 Ackley Improved?
- Thread starter Algonquin
- Start date
I have a 30 Gibbs, which is about as much capacity as you can wildcat a 30-06 to. It gives a flat 100 FPS gain on my standard 30-06 with similar bullets and barrel lengths. Not a lot, but is does flatten the trajectory slightly. If you are not a dyed-in-the-wool gun "nut", don't bother with wildcats. There is always a standard chambering that will get you the performance you desire. I personally have several wildcats, but I do fall into the above mentioned category, so don't mind the fiddling involved with brass, headstamps, etc, etc. Regards, Eagleye
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- Somewhere on the Hudson Bay Coast
An issue that comes up when shooting straight wall rounds at very high pressure is that there is more pressure exerted on the locking lugs, because there is less resistance to the set back of the case against the bolt face. I good recipe for disaster would be to use an AI case loaded to very high pressure, then inadvertently moly-coat the chamber when you are treating the barrel.
Edited to add . . .
See my post below.
Edited to add . . .
See my post below.
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Any reasonable caliber with a decent bullet placed in the heart/lung area of a moose will kill him.A lot of folks have success with a 270, I know a fellow who has taken a fairly large grizz with a 270, not my cup of tea but it does work. I have played with many wildcats and the main reason to have a 30/06 imp is simply because you want one.There is always something bigger and faster.There are so many great factory cartridges, that wildcats are not really needed unless you simply want one.
It's really too bad the 30 Newton did not survive better than it did for those wanting more than the 06 could provide. It was more of a step up from 06 velocities but as you will see still not to 300H&H speed. This is from 1937.
The standard 06 may be boring to some but it is also hard to beat. For 75fps more it would not be worth it IMO.
The standard 06 may be boring to some but it is also hard to beat. For 75fps more it would not be worth it IMO.
Yes, thank you.
As for the other "improved" 30-06 siblings, the 270 and 280, I have both. If mule deer and pronghorns were also on my list to hunt, I would choose one of those over a 30-06. I have not hunted with my 280 yet, but note that it will handle a huge range of 7mm bullets available to the handloader.
I once ran an accuracy comparison in 6.5x55, 270, 280 and 30-06. I happen to have a M70 in each caliber. The 30-06 is a "Ranger" (el-chepo). It shoots the best. Around 1" with match bullets. The worst is the 6.5x55. That was a surprise. It groups around 2' with match bullets.
I bought the Ranger at the local Canadian Tire. It was not selling and they kept dropping the price. When it hit $165 I could not stand it any longer and bought it. Turns out a friend of mine was watching it too, and was waiting for $150. Snooze - ya loose.
- Location
- Somewhere on the Hudson Bay Coast
A kind soul has just sent me a PM, pointing out that I am a pin head. Anyone who has read PO Ackley's Handbook, me included, will know that a case with minimum taper will reduce case set back not increase it.
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First of all, it was not me who PM'd you, and not me who called you or anyone else a pinhead, but I took what you said earlier (shown below) the same way as did your anonymous critic. You seem to be saying that straightening out the case walls such as by "improving" a case by reducing taper, will increase bolt thrust, when in fact Ackley theorized that it would reduce it.
If I am mistaken on what you (or Ackley said), I am sorry.
All that aside, not everyone agrees with Ackley about the notion of a straight-walled case exerting less bolt thrust than a tapered case. His "experiment" was hardly scientific, yet has been embraced as "gospel" by the vast majority. The idea is that a tapered case will literally "squirt" out of the chamber, and the less the taper, the less force against the bolt.
I am an Ackley heretic in that regard, and hold to the idea that the case will solidly grip the chamber walls, and all the rearward force exerted is due to the unsupported portion of the case stretching against the boltface, "ignoring" the shape ahead of it. Ackley unwittingly proved this with his famous firing of an unsupported case in a gun. His use of an improved case seemed to prove that it was the reduced taper (reduced, not no taper) that held it, when in fact the same would have happened with the original taper.
Bolt thrust in a dry chamber was long ago determined to be simply the product of pressure and the area of the casehead. A lubricated chamber (and/or cartridge) will add to the bolt thrust, but the amount of difference between a straight-walled and tapered cartidge is negligable.
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Certainly don't want to get into a pissing match here but I must respectfully dissagree if you're saying a very tapered case will take the same pressure as a fairly straight sided one. I've had a few straight sided wildcats so I'm not just blowing hot air. Look at the 30-30 AI. In the week 94 action you can only load the factory speeds. AI it and you can go faster even in the 94. Yes I agree that the case should grab the chamber wall regardless of shape, and it does but the straight ones do it a little better.
My two 30-30 Ackleys demonstrated quite conclusively, to me anyway, that the straight case reduced bolt thrust. Here's how: both the Model 94 and the Marlin took seven grains more powder to get a "sticky" lever than before they were rechambered. The standard working load in the Imps was 150s at 2600. 
As well, the first 250 Imp I had built was done by PO himself. He did up a Rem 600 for me with one of his barrels, and the chamber was so smooth, you could actually blow primers, without any indication whatsoever of any probelms coming, untill you added the extra half a grain of IMR4320 powder. This is exactly what Andy is referring to in his first post in this thread, about very high pressures being used in improved chambers.
On the other hand, I had an old 270 Husqvarna for twenty-some years that digested more than 4000 rounds of 130 bullets ahead of 4831 before the barrel was toast. It got 3200 fps over the Oehler with that load, and it was the standard chamber not an improved.
Ted
As well, the first 250 Imp I had built was done by PO himself. He did up a Rem 600 for me with one of his barrels, and the chamber was so smooth, you could actually blow primers, without any indication whatsoever of any probelms coming, untill you added the extra half a grain of IMR4320 powder.
This is exactly what Andy is referring to in his first post in this thread, about very high pressures being used in improved chambers.On the other hand, I had an old 270 Husqvarna for twenty-some years that digested more than 4000 rounds of 130 bullets ahead of 4831 before the barrel was toast. It got 3200 fps over the Oehler with that load, and it was the standard chamber not an improved.
Ted
I thought that everybody knew that the 30-06 improved is the 35 Whelen, mine is actually a 35 Whelen AI, why, just for something to do. From what I have read some of the greatest gains with the Ackley Improved profile are with the 257 Roberts cartridge, with the 35 Whelen it is only about a 5% gain.
The Whelen is already a very efficiet case. When you open up the Bob, you're giveing it a bunch more capacity along with the sharp shoulder. I had a 375 Ackley for a while and it gets a huge improvement going to the AI form, mostly from the displacement gain.
Apples to apples, orangesn to...
The reason the 270 looks so good id simply that it is jacked up to magnum pressures. No other "magic" required.
The simplest way to "jack-up" a strong old 30-06 is to ream it to 308 Norma. There are lots of gunsmiths who have the reamer and will do the job for a reasonable price, providing that you give them a safe rifle to build on.
The reason the 270 looks so good id simply that it is jacked up to magnum pressures. No other "magic" required.
The simplest way to "jack-up" a strong old 30-06 is to ream it to 308 Norma. There are lots of gunsmiths who have the reamer and will do the job for a reasonable price, providing that you give them a safe rifle to build on.
If tapered cases did not grip the chamber walls, 303's would not separate cases. If tapered cases did not grip the chamber walls, 30/30's with excessive headspace would not produce protruding primers. Ackley's theory is just that; a theory. Although a straighter walled case may grip the chamber wall better, the difference is not demonstable because the taperedcase grips sufficiently well to retain the brass in the chamber.
At low pressures, a lubricated chamber will affect bolt thrust. At high pressures it will not. At high pressure, the thrust exceeds the yeildstrength of the brass and it's contribution becomes essentially nil.
Tapered cases will cause a sticky lever sooner because, once the pressure is gone, the springy lever action wedges the tapered (and now stretched) case into the chamber and it sticks, The improved cartridge, with it's sharp shoulder, resists this better so the lever doesn't stick as much.
I am, generally speaking, not a fan of the improved cartridges. If one wants 300 magnum performance, he needs to get a 300 magnum. Regards, Bill.
At low pressures, a lubricated chamber will affect bolt thrust. At high pressures it will not. At high pressure, the thrust exceeds the yeildstrength of the brass and it's contribution becomes essentially nil.
Tapered cases will cause a sticky lever sooner because, once the pressure is gone, the springy lever action wedges the tapered (and now stretched) case into the chamber and it sticks, The improved cartridge, with it's sharp shoulder, resists this better so the lever doesn't stick as much.
I am, generally speaking, not a fan of the improved cartridges. If one wants 300 magnum performance, he needs to get a 300 magnum. Regards, Bill.
