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Fred Zeglin

P.O. Ackley Quotes: Famous Words Of Wit And Wisdom

Best known for his Ackley Improved family of cartridges, the eminent gunsmith P.O. Ackley was also a tireless self-promoter and well-known writer. Here are some of our favorite Ackleyisms.

  • P.O. Ackley made no secret of his disdain for many popular magnum cartridges.
  • Ackley responded to hundreds, perhaps thousands of personal letters.
  • The man was multi-talented when it came to gunsmithing.
  • He could make the finest barrels or blow up the strongest actions.
  • And he could offend the thickest-skinned of the rifle intelligencia.
P.O. Ackley
Photo of the man himself, P.O. Ackley, from the collection of gunmaker Jerry Fisher. Fisher visited Ackley in the mid-1970s and remembers him talking about all facets of gunmaking. Making a living was a key subject in the discussion.

Best P.O. Ackley Quotes

As Col. Charles Askins once said, “With a total interest in the shooting game, with a dedication and a devotion to rifles and their loads, the man had given countless hours, money and effort to the betterment of the existing American family of rifle cartridges. The debt of the shooters of this country to Parker Ackley is a major one.”

P.O. Ackley was careful about the words he published for the general public verses the comments he might write to a friend. A few examples of these comments come from his private letters written to friends and acquaintances.

For example, on large capacity magnums he declares, “Of course, these big ones make more noise and they would be highly efficient if you could scare animals to death.

Letterhead-logo
Letterhead logo from the early days in Trinidad. Collection of Ron Pearson.

“If you look through my Volume I book you will find that about 2,800 fps is about all anyone has been able to get out of a .35 caliber 250-grain bullet, regardless of what case is used,” Ackley wrote to Bevan King. “So anyone claiming 3,400 is either using some highly specialized system or he is a liar. And I am pretty much of the opinion that the latter is correct.”

So, without further ado, here are some more of our favorite Ackley quotes.

Ackley On Extreme Accuracy

Discussing extreme rifle accuracy Ackley wrote to a friend that, “There are not a very high percentage of the shooters who are able to shoot like that no matter how well the gun is made or how accurate it is. I have noticed that some benchrest shooters or target shooters would shoot fifteen or twenty groups and then throw away all but one and then they would brag about their rifle being able to do that every time. You should have seen some that had been thrown away. The more rabid they get on the accuracy kick the more psycho they become.”

Ackley-On-Extreme-Accuracy
“I have been making barrels for forty-four years or more and I don’t know half as much about it as someone who has been at it four years,” said Ackley to a friend.

Parker On His Critics

“I have been making barrels for forty-four years or more and I don’t know half as much about it as someone who has been at it four years,” said Ackley to a friend.

Insights Into Elmer Keith

“I don’t think Elmer Keith would be caught dead hunting with anything smaller than a .300 Magnum. And he used to tell me that was about minimum for deer. For other stuff he starts up from there. Of course, if you figured things proportionately, guns for moose or bear; the gun would probably be at least 37mm,” Ackley wrote.

Dressing Down Bureaucrats

On property tax Ackley declared, “When I sold the land out back I intended to fix up the house. When we moved to Holiday in 1951 … taxes have gone up so much that I am just letting the joint fall down. If I do any work on it they will come around and reassess it. Like everywhere else we have a surplus of public parasites.”

Dennis- Belm-consulting-P.O-Ackley
Dennis Belm (right) consulting P.O. Ackley (left).

P.O. Ackley On Gunsmithing

“The smoothness thing which is so often proclaimed in the various discussions of the .17 caliber barrels is a myth. It sounds good but it has no basis in fact. I have worked with .17 caliber barrels now for more than 25 years and although I admit I don’t know very much about barrel making after more than 30 years at it, I do know that the best way to get an answer to the problem is to ask someone who has never made a barrel. They can always tell you.”

Taking Down More Magnums

[Magnum cartridges are] “so inefficient that no one in his right mind could see anything good in them except sales possibilities … It would be fine if by putting a belt on a case and advertising it as a magnum it would revolutionize the industry, but it only revolutionizes sales.”

P.O. Ackley On His Competitors

“I have no quarrel with the man who has a lower price. He knows better than anyone else what his product is worth.”

Editor’s Note: This excerpt is from P.O. Ackley: America’s Gunsmith available exclusively at  GunDigestStore.com.

Ammo: Does Case Shape Really Matter?

There have been a number of factory and wildcat cartridges that have played with case design. But has it had any real effect on ballistics?

Hot shots about a case design's effects on ballistics:

  • As far back as 1946, gun writers and experts already concluded case shape had no effect on velocity or pressure.
  • No matter how a case is shaped, if it is measured against one of the same caliber and capacity, it will have near identical internal ballistics.
  • Col. G.O. Ashley did a load of range work comparing the .257 Ackley and a wildcat of the same caliber called the .25x60mm C.A. to support the conclusion case shape has little to no effect on ballistic performance.
  • Despite this evidence, there are still wildcatters and manufacturers who claim to have innovative case designs and promise the moon when it comes to performance.
  • Ackley himself acknowledged the limitations of cartridge design, saying: “There is no evidence which substantiates the claim that one cartridge design is more accurate than another.”

As far back as July, 1946, American Rifleman ran an article by C.C. Merideth discussing this very question of case design. His conclusion, “… we must arrive at the conviction that any variation in pressure to velocity ratio ensuing from any alteration in chamber shape is negligible as compared to other purely mechanical changes, such as altering bullet diameter, wear in the throat and many other possible differences between any two apparently identical rifles.”

Bob Hutton knew of the Merideth article mentioned above; he was sure he could disprove the conclusions drawn there almost 20 years earlier. He created a wildcat with the same case capacity as the .219 Donaldson Wasp in a short, fat configuration. Prior to testing, he expected that the design would allow the use of slower burning powders for better overall results. In testing, he found that it required the exact same powder and charge and delivered identical results.

case - A cartridge’s energy is often touted as the measure of its knockdown power when, in fact, it is more indicative of the round’s killing power.

Hutton, while discussing the concept of modern cartridge design (including improved cases), wrote, “Shape, in the mathematics of interior ballistics, makes no difference.” It's important to understand that we are talking about internal ballistics not how the case functions in a given chamber design. The idea is simple and easily demonstrated. If a cartridge holds 40 grains of powder and if all other variables are equal it will produce statistically identical results along with any other design of the same caliber with any shape chamber you can imagine so long as it also holds 40 grains of powder.

Col. G.O. Ashley did an article that required a fair amount of actual range work. He and a couple of gunsmiths used a .257 Ackley Improved and a wildcat called the “.25x60mm C.A.” The idea was to have cartridges of the same caliber and capacity with totally different shapes (the exact discussion we are interested in here). The two cartridges ended up within 1.1 grains water weight capacity, about as close as you could get. These tests showed that the Ackley case delivered between 3 and 12 fps more velocity than the .25x60mm C.A., statistically that is a zero, especially since the 1.1-grain edge in capacity belonged to the Ackley Improved. All this is in support of Hutton’s statement that case shape has no effect on internal ballistics or how the powder is consumed in the process of driving a projectile down the bore.

Most recently, the SMc line of cartridges came to the market. Mic McPherson and By Smalley partnered to create www.superiorballistics.com (a now defunct web site) to promote their ideas. “SMc naming designation accounts for caliber and usable case capacity. For example, our 5/35 SMc is a 20-caliber (5mm) cartridge holding about 35 grains of water (to base of neck). One important patented design characteristic of all SMc cartridges is a powder column that is between about 2 times and about 2.1 times bullet diameter.”

case - Figuring out the greatest cartridges of all time has the benefit of having to test a ton of ammo.

This is the newest design to claim improvements in ballistics via case design. In reading over the data provided on their site no pressure data was provided. Knowing that pressure and velocity are directly correlated you have to assume from the velocities reported for the 5/35 SMc that they are not afraid to load hot. Now to be fair, they are using high quality brass and this probably helps with handling pressure as the cases are relatively thick in the wall and designed for top pressures.

The only new information that this line of cartridges brings to the table is a fairly extensive test of barrel heating. The conclusion of McPherson in a nutshell is that the SMc design produces less barrel heating and possibly less throat damage than other cases tested.

It appears from the data reported that contentions about barrel heating were proved out in McPherson’s tests. He went on to say that the test should be repeated to insure the results were accurate. So, how does this relate to our axiom that case design has no effect on internal ballistics and velocity? I would say that only further testing could determine if the ideas of the SMc really have merit. Nearly thirty years of experience in gunsmithing, reloading, and barrel making tell me that it’s not likely that any increase in velocity is a result of the design in question, but rather a result of hot loads.

So where does the increased velocity come from in an Ackley Improved case design? It’s very simple — more case capacity. Ackley did not merely change the shape of the case. He added, in most cases, a fair amount of case capacity, which allows for more powder while holding the overall pressure to the same limits. This added capacity is only available for increased loading after the cases are fireformed to the chamber.

Customers often ask, “What pressure does that wildcat operate at?” The answer is, exactly the same pressure as the factory counterpart, or parent case.

Ackley thought he could exceed the pressures of the factory cases … that might be true with antiquated designs like the .30-30 WCF or the .25-35. Cases with a lot of taper were often originally held to lower chamber pressures. It is not true of more modern designs that already have relatively straight walled cases and sharp shoulders, also modern cases normally are designed for higher pressures. A good example of a high pressure design is the .270 Winchester, it was one of the first cases to be loaded to full potential by the factory, modern SAAMI specifications show the .270 at 65,000 psi.

Case - One of the better groups shot from the author’s custom .280 AI. The Nosler Custom 140 gr. AccuBond outshot reloads in the accuracy department.

The .30-06, which many consider to be modern in design, is limited to 60,000 psi by SAAMI. The factories tend to load .30-06 ammo below that pressure level. Why? Because there are large numbers of older and often weaker rifles in general use, so it is wise of the factories to hold those pressures down.

In the case of the .270 Winchester, it was never available in these weaker actions from the factories, and they do not have to take responsibility for custom guns on old actions, so they load it to full potential. This gives us an insight into the reason that Ackley perceived his .270 AI to be no real improvement over the .270 Winchester.

Once fireformed, a .30-06 AI can be loaded to the full potential of the brass. In a modern high quality action that is at least 60,000 psi, and most wildcatters will go straight for the 65,000 psi as SAAMI uses with the .270 and many other modern cartridges.

If you check the pressure on the average handload in any caliber you will find that it is well above the pressures of factory ammunition. So it’s easy to see why folks think that case shape increases velocity. In reality it is simply more powder and the fact that you are probably loading hotter than the factory.

Ackley should have the final word here. “There are no Wildcat cartridges which are actually revolutionary. There are a few which fill gaps between existing commercial cartridges. There are many more which are no better and perhaps not as good as their commercial counterparts.

“There is no evidence which substantiates the claim that one cartridge design is more accurate than another. It certainly cannot be demonstrated that inaccurate barrels can be made more accurate by simply rechambering them to some so-called ‘improved’ cartridge or Wildcat caliber.”

Editor's Note: This excerpt is from P.O. Ackley: America's Gunsmith available exclusively at GunDigestStore.com.

Experimenting with Bolt Thrust

Bolt Thrust - pressure and velocity data
Collecting pressure and velocity data at the range.

Since the post-WWII years, if not before, there has been an ongoing argument concerning whether breech thrust (bolt thrust) is reduced by the improved case design. P.O. Ackley has certainly influenced the argument. The definition of an improved case is pretty simple. The case body is blown out to minimum body taper, which is described by Ackley as 0.0075 per inch taper. Shoulder angles between 28 and 45 degrees are normally considered to be improved, although it could be argued that any shoulder sharper than the original parent case is improved. Finally, an improved design allows the firing of a factory cartridge in order to fireform the brass for the new design.

Shoulder angles between 35 and 40 degrees seem to provide the advantage of minimizing brass flow without negative effect. When the shoulder angle is greater than 40 degrees, brass is unnecessarily hard to form and chamber reamers do not last as long. Headspacing becomes much more critical with a sharper shoulder because there is less taper, making it harder to hit the correct measurement. Also, sharp shoulder angles do not feed as smoothly as more tapered ones. When the shoulder angle is less than 35 degrees, brass flow becomes more of an issue. There are some cartridges, like the .220 Swift Improved, which do not receive any real improvement in velocity, but are popular because they improve brass life by arresting stretch, thereby increasing brass life.

It is not unheard of to measure breech thrust, however the cost of tooling for such testing made it impossible for the purpose of writing this book. However, a method of recording breech trust was necessary in order to go beyond the somewhat subjective experiments that P.O. Ackley wrote about in Handbook for Shooters and Reloaders Vol. I. There Ackley used a Model 94 Winchester because, as he stated, “We often hear that the Winchester Model 1894 action was designed for low pressures and is an action which could be described as ‘weak.’” The purpose of his experiment with the ‘94 was to prove that the improved case design minimized bolt thrust; that the brass will support and contain some pressure; that oily chambers increase bolt thrust; and finally, the notion that actions are designed for specific pressure ranges is a fallacy.

Bolt Thrust - Firing mechanism
Firing mechanism, adjustable for headspace and firing pin length.

Our Test
The Pressure Trace (a product of Recreational Software, Inc.), was used to measure the chamber pressure for all ammo tested in this chapter. The goal of this test was to repeat Ackley’s experiments with the .30-30 Ackley Improved, but to increase the value of the data collected by taking measurements of the thrust against the bolt face. This experiment is repeatable. The author designed and built a custom jig to hold a .30 caliber barrel with a universal breech plug to allow for adjustable headspace, and to accommodate the strain gauge utilized by the Pressure Trace. The firing pin had to be designed to allow for headspace adjustment, too.

The initial tests were done with factory loaded ammunition in .30-30 Winchester to provide a baseline comparison. The second wave of tests was performed after the barrel was rechambered to .30-30 Ackley Improved. The breech of the barrel was turned to 1.050 inches so that wall thickness would be thin enough to provide good data with the relatively low-pressure factory .30-30 Winchester loads. We also left the wall thickness in the area of threads as large as possible so that it would be less likely that the breech would expand, allowing the breech mechanism to move rearward and partially nullifying our test results.

The bolt thrust test had the following goals:

  • Determine empirically if the cartridge case does indeed contain some pressure at factory levels.
  • Determine difference in bolt thrust between factory and improved designs, if any.
  • Determine if chamber pressure can be increased over factory with the same bolt thrust regardless of pressure.

For the .30-30 AI, run pressure up to the point where the brass separates, and compare results to mathematical predictions.

Oil cases to see if bolt thrust is increased with the same load as Ackley stated.

Extend the experiment to other cartridges.

Bolt thrust - prescale film
Prescale film in place, note the hole in the film for the firing pin.

.30-30 Test
In this first stage of testing with factory ammunition, we fired 60 rounds to work out technical issues, and insure that the test rig would work for the designed purpose. While firing these early test rounds we also checked to see if we could fire rounds with excessive headspace as this was part of Ackley’s earlier tests. We first fired a batch with .010-inch headspace. The cartridges were pushed forward so that the rim was in contact with the breech of the barrel. When fired, the primer backed out .010-inch to take up the headspace, the case stayed fully forward and did not measurably stretch.

We then experimented and found that the maximum amount of excessive headspace we could generate without the primer failing was .046 inches. When we exceeded this amount the primer ruptured and left us with lots of pieces and carbon in the breech gap.

Thus, before we even started the test in earnest, we had proven that the cartridge case of the .30-30 Winchester can contain all of the pressure of a standard factory load without stretching and that the primer is actually the weakest part of the cartridge. That bit about the primer is no real surprise to you reloaders.

Bolt thrust - 30-30-Win
Ammunition used to provide this reference sample, Federal Power-Shock.
bolt thrust - 30-30 Ack- rechambered
Ammunition used to provide this reference sample, Federal Power-Shock.

bolt thrust - 3030-Ack-ImpThe reason the neck and shoulder are dimpled in the photo this chapter is simple. Gasses slipped back around the neck. It is likely that the pressures were higher in the barrel than in the case once the primer failed — venting gases into the breech gap. So the higher pressure gas in the barrel was seeking an outlet around the case neck.

Once we were confident in our results, we then recorded the data listed in the table below by firing 10 rounds of each load. Average readings are used to help keep all comparisons apples to apples. The factory ammo did produce some pressures over 40,000 psi, which means it is loaded close to the safe limit set by SAAMI.

A product called Fujifilm Prescale offered by Sensor Products, Inc., of Madison, New Jersey, was used to record bolt thrust. Prescale is a Mylar-based film that contains a layer of tiny microcapsules. When pressure is applied to the film the microcapsules are ruptured, producing an instant and permanent high resolution image of the pressure variations across the contact area. The film we used was .004-inch thick and comes in varying pressure sensitivity. By placing the film between the case head and the bolt face we are able to take a reading of the exact and true bolt thrust in real time. The film can also be sent to the company for computer analysis, which will reveal the exact pressure exerted, including detail of where the pressure was applied and where it was less intense.

Bolt thrust - seating depth
Note how easy it is to spot headspace from the primer protrusion on a .30-30. Case on the left has zero headspace.

Seating depth in all the loads listed for the .30-30 Ackley Improved here was 2.535 inches, seated to the canelure of the bullet. Note that the last load in the table above, 35.5 grains of IMR 3031, is a compressed load, and there is no room for any more powder. This is approximately 140 fps faster than published data for this powder and bullet weight in the standard .30-30 WCF, and there is clearly not enough room with this powder to get into pressure problems.

The 35.5 grains of H322 was used as it produced factory level pressures in the .30-30 AI chamber. Excessive headspace of .010-inch was set. When fired, the case did not move back, the primer backed out and marked the Prescale film. Edges of the film show color only because the film was cut to fit the case head. The color or light readings around the primer pocket are “noise” from the vibration of the bolt during the firing of the mechanism. This was proven by dry-firing the mechanism, during which similar marks appeared in the film.

bolt thrust - 30-30-ackley-over pressureWhen you study the table following here, it will be obvious that we have exceeded the SAAMI pressure limit of 42,000 psi with H322. This powder allowed us to get more powder in the case because of its smaller granules. 35 grains would be the safe maximum in our test barrel if you were staying with the SAAMI pressure limit, and at 2,600 fps we are nearly 400 fps past the published data for the same powder and bullet weight in the .30-30 WCF. Of course, this is only true in our test barrel, it would be necessary to use normal load development for any individual firearm, as we were able to generate far more pressure than is advisable in a .30-30 AI under normal conditions.

Those loads that exceeded the 42,000 psi limit were tested for two purposes: To see how much pressure could be generated in the .30-30 AI case, using powders that are appropriate in burning rate for said case. And to determine at what point the brass will yield and stretch with excessive headspace.

bolt thrust - 30-30-ACK-4895

bolt thrust - 30-30 Ackley improved
The above two tables show that the .30-30 Ackley Improved delivered an additional 180 to 200 fps with these powders in our test barrel. The pressure curve on the H4895 loads had an undesirable form in the .30-30 AI: instead of the pressure curve rising early and tapering off, we found that it had a second pressure spike much higher than the first just before the bullet exited the barrel. For this reason alone I would avoid this powder in a .30-30 class cartridge. *Exceeds SAAMI Maximum.

We started with 0.000-inch headspace as before. The oil on the cases did not allow them to adhere properly to the chamber walls under pressure. Consequently they moved to the rear and applied full pressure or bolt thrust to the bolt face.

This is a stark comparison to the earlier test where the dry case was able to adhere to the camber wall and only the primer backed out against the bolt face.

Bolt thrust - cases
The brass from our hottest loads shown here, were intentionally shot with excessive headspace. Expansion of the brass to full chamber diameter is normal and can be seen on the fired case. The expansion line on the bottom case is where you would expect to see case stretch if it were present. Looking across at the sectioned case, there is no sign of stretching of the case wall, i.e. no thinning of the case wall.

So, was Ackley right about his findings?
Yes, but he may have missed a point or two.

Since .30-30 brass is thick and pressures are low relative to brass strength and case capacity, with most appropriate powders pressure is not a big problem. To be fair, we did find some powders that will develop pressure far beyond SAAMI levels for the .30-30 AI case. Because the brass is so thick, it actually cannot stretch and cause head separations due to excess headspace. In that respect the .30-30 is not a good choice for Ackley to prove that improved designs handle pressure better.

However, Ackley used the .30-30 because the ‘94 Winchester action had been labeled weak. In this respect, Ackley did prove that the ‘94 can handle anything the .30-30 or .30-30 AI can dish out, without any question.

Editor's Note: This article is an excerpt from P.O. Ackley: America’s Gunsmith.

The Ins and Outs of Fireforming Cases

Fireforming
Top is a fully formed case. Bottom is a factory case in the improved chamber.
Fireforming
Learn all about P.O. Ackley and his contributions to the firearms world with P.O. Ackley: America’s Gunsmith.

Rimless and rebated cases are easy to fireform for Ackley chambers if the headspace is correctly set as described earlier in this chapter. You can fire factory ammunition for the parent caliber in the chamber with no ill effects. The result will be velocity slightly reduced as compared to firing the same load in a standard chamber. This loss of velocity is primarily as a result of energy being used to form the brass, secondarily because the larger volume of the improved chamber requires more powder to get the same velocity.

Rimmed or belted designs headspace on the rim or belt respectively so you can fire factory ammo and in most cases will produce good results most of the time — even though the shoulder is often blown forward. One exception would be using old fired brass: often it is too brittle and will split during fireforming. So using new unfired cases is recommended for fireforming.

If you happen to have a wildcat that requires a large amount of forming, firing factory ammo will sometimes cause an unacceptable loss of brass, resulting in split cases. This happens because the cases expand so quickly that if there is a flaw or weak spot in the brass it will pop like an overfilled balloon. One example of this would be the .219 Zipper Ackley Improved. If you experience this there are two possible solutions. Try annealing the neck and shoulder down the body to as much as half way along the body. Make sure you do not anneal the case head or the thick web area just above the head. Annealing the head will greatly reduce the case’s ability to handle pressure. Once annealed, load the cases as normal and try fireforming a few. Initially don’t load more cases than you are willing to pull bullets from.

Fireform using corn meal or “Cream of Wheat.” George Nonte, in Home Guide to Cartridge Conversions tells how to develop fireforming loads using no bullet. In Custom Cartridges Ken Howell expanded on the concept.

Fireforming
Standard headspace gauges.

First insert a spent primer (for safety) in an unformed case. Fill the case with Bullseye® pistol powder to the top of the neck (DANGER, never to be fired). Then pour this charge into the pan of your powder scale and weigh the charge. Divide that amount by 10, so that 1/10 of the total volume will become your starting load. Now take that 10 percent load for your case and put it in your normally primed case. It may take some testing to get a load that fully forms the case. Tear a single sheet of toilet paper in quarters, insert one quarter as a wad over the powder charge. Now fill the rest of the case with your inert filler (corn meal, or fine ground hot cereal, etc., dry of course). You will want to place a wad of some sort over the cereal so it does not spill. Bees wax, bullet lube, or toilet paper work, it must be light enough so that the wad can be blown down the barrel without doing any damage.

You are ready to fireform a case. Keep in mind that even without a bullet these loads could be deadly, so use all normal gun safety practices. Pointing in a safe direction fire the first load. If it is not fully formed, bump your 10 percent load by one-half grain at a time until you get a fully formed case. It is possible to generate dangerous pressures if you use too much powder in these inert filler loads, so be careful. The interesting thing about this method is that it will often form cases without any loss to ruptures when a factory load will cause ruptures.

L.R. Wallack wrote this method up for American Rifleman. After describing the method he said, “I then did 10 cases with this load with no splits and all formed nicely. Such success has been practically unheard of, as anyone who has formed cases for this wildcat well knows. I have no hesitation, therefore, in recommending the method.”

Editor's Note: This article is an excerpt from P.O. Ackley: America’s Gunsmith.

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