Ask the Instructor: Comb Adjustment

Source: Ask the Instructor: Comb Adjustment

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Hartmann’s Hints: Breathing

Source: Hartmann’s Hints: Breathing

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Cryo Barrel Treatment

Dear Readers,

I have never had a barrel cryo treated and so have no personal experience but, as you read in previous Technoid screeds, my inclination is to think that it is of little practical advantage to a shotgun shooter. Being a Luddite, I am not a big believer in most aftermarket “improvements”, such as including porting and backboring, either. I thought that you might like to read the following letter, especially since Abe agrees with me and uses even longer words.

Best regards,

Bruce Buck
Shotgun Report’s Technoid


Disclaimer: The information following may ignite a Jihad at Shotgun Report. I don’t know if you’ll want to publish it, but I think you should know all the same.

You recently discussed Cryogenic Barrel Treatment in your updates. Cryo freezing has been touted as a panacea for just about everything – “Makes Harleys run more fuel-efficiently; makes brass instruments sound fuller; makes guitar strings last longer (no kidding!); makes pocketknives stay sharp longer; makes firearms more accurate, resistant to wear and rust, better looking, more deadly, etc., etc., etc.”

I’ve got a lot of friends who are all metallurgists. Lots of them are shooters. Do you know how many have cryo-treated barrels? None.

The science behind it does not support cryo-treatment as being the panacea that it’s touted as. I am 100% certain that it improves some alloys. But it does not improve ALL alloys (i.e. ALL steels). The bottom line is that cryo-treatment is supposed to remove the last little pockets of a material called Austenite from the steel.

Austenite pockets CAN weaken steels. However, the process for removing Austenite can vary GREATLY between types of steels, based upon their stoichiometric composition and forging history. Do you know the AISI-SAE classification number of your barrel’s steel? If you don’t know, how do the Cryo guys? How do they know which process is right for your barrel?

There are a large number of people who believe that cryo-freezing is the only thing that keeps their bullets on the target. There are also a large number of people who believe they can’t hit a clay pigeon unless the lettering on their shells lines up just right. Having faith in a process doesn’t make it work as advertized. The power of the mind is an amazing thing. If I paid $50 for an improvement to my gun, you can bet I’d get an improvement one way or another. But it could be a confidence game. If I have absolute confidence it worked, I will most likely shoot better.

I have yet to see a test by one of these cryo companies that makes an effort to remove any sort of a “Placebo” effect. Why do you think that is? I met one guy who bought a brand-new pistol and never even test-fired it for accuracy before getting it frozen. He just KNEW that it would be inaccurate unless he had it frozen. Last I heard he was shooting better with his cryo-treated gun than he had been with his old gun. But that’s ANECDOTAL evidence, not SCIENTIFIC.

I’m not saying that cryo-treatment is a fraud, but I am saying that I’ve never seen a one-step solution that improves EVERY property of EVERY alloy. It probably won’t destroy your barrel, but whether it’s worth $50 to find out if it helps is your call.


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Jacob Jostles Her Way Onto Another Worlds Podium | USA Shooting

Source: Jacob Jostles Her Way Onto Another Worlds Podium | USA Shooting

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Gaussian Patterns

Dear Larry:

You asked, “…you continue to refer to patterns as Gaussian,…”” Where is your proof of this very doubtful theory?”

Your question is just right. Everyone should always ask for proof of theories. In this case the short answer is that the proof is in the pudding, or rather, in the pattern data. But since short answers aren’t any fun, bear with me while I expand on this.

When I first started my study of shot patterns quite a few years ago and put together the SPRED model (or theory), which is Gaussian-based, I thought initially that I was the first one to discover that shot patterns followed the Gaussian distribution. After doing more homework, however, I found that the idea had been around since the 1920s, when a French artillery expert named Journee started writing about it. Subsequently, Ed Lowry, John Brindle, and Roger Giblin extended the theory to shotgun patterns. My focus has been on extending the practical applications of this concept with Choke Chooser(tm) and other products.

OK, back to your question: where is our proof? The proof is in the shotgun pattern data sets that have accumulated over the years. If you were sitting here with me, I could show you several batches of data which I think would convince you. It’s harder to do via email, but let me try. I started with some of my own pattern data, then went on to that of Oberfell and Thompson (O&T). The strange thing about O&T is that all the pattern data in their book follow the Gaussian model extremely closely, yet they never explicitly recognized it. They just made no attempts to apply theory. The closest they came was to say that the data “appear to follow the laws of probability”. Loosely translated, that means the Gaussian model.

Another excellent data set comes from the pattern tests performed and published by American Rifleman. With assistance from others, I’ve compiled 21 years of Rifleman data, from 1978 to 1998, consisting of over 300 high-quality data points in all. I plotted these and compared them with the Gaussian model. Again, the agreement is truly remarkable. I’m planning to publish some of these comparisons soon.

Additional, but less convincing, support for the theory comes from statistical reasoning. The Gaussian distribution occurs extensively in nature. That’s why another name for it is the “normal” distribution. After studying these phenomena, theoreticians (i.e., Herr Gauss and others) were able to show the following, probably the most important axiom in the entire field of statistics: data that are influenced by many small and unrelated random effects are approximately normally distributed.

This explains why the normal or Gaussian distribution is everywhere: stock market fluctuations, student weights, daily maximum temperatures, SAT scores, and yes, shot patterns. In the latter case, the travel of each pellet is independently and randomly influenced by numerous small effects: air turbulence, temperature fluctuations, aerodynamic forces on pellet flat spots, and many others.

See, the long answer really is a lot more fun, right?

Best regards and happy shooting,

Warren Johnson

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Paper Or Plastic Shells

Dear Technoid,

I was talking to a buddy at the shooting club about paper shells. He said he liked them better because he feels less recoil from them. He also stated his gun is much cleaner with less powder residue in his barrel and reach.

I know companies used to make paper hulls in the 1950’s and earlier.I can figure that Plastic is cheaper for the companies to use than paper, thus the move to plastic hulls.

Is there any advantage to paper hulls over plastic? Does the paper hulls crimp open more evenly than the Plastic counterpart at firing thus giving a better pattern and burning more evenly the powder?


Dear Mark,

The largest manufacturer of paper shells in the US is Federal. Their paper shells are quite popular among target shooters because many do believe that the paper tube and paper base compress slightly on ignition and thus lower recoil just a little bit. I know one guy who shoots them because he says that they smell better. The shells that Federal supplied to our Atlanta Olympic shooting team were their paper hulled versions. I have one of Kim Rhode’s 24 grammers.

No one has been able to prove to me that the paper hull produces any better patterns than the plastic hull and I have never heard Federal claim it. I think that it is all a perceived recoil thing. When Andy Duffy, was sponsored by Federal, Andy chose their paper shells and felt that they give him just a little less kick.

The paper shells cost an extra few dollars per flat. I don’t know if they are more expensive to make or whether there is something in economy of scale when compared to the vastly greater number of plastic hulls Federal uses. It may be a simple marketing ploy.

Do they burn cleaner? Not hardly, but maybe. Sort of. Federal uses various burning rates of powder in their 12 gauge loads, depending on shot load and velocity. I don’t believe that they use a different mix of powder just because it is used in a paper or plastic hull, so the paper hulls would have no advantage there. BUT, there may be a slight cleanliness advantage to the paper hull IF they seal to the chamber walls under expansion better than the plastic Reifenhauser hulls that Federal still uses. I don’t know this to be a fact, but if it were, I wouldn’t be surprised. The tighter the shell seals to the chamber wall, the less blow by you get in the receiver. That would make it cleaner- especially in a gas gun.

One problem with paper shells is that, in spite of their wax coating, they are subject to swelling in wet or humid conditions. They are also more easily affected by storage under damp conditions. I have seen paper hulls so badly swollen that they would not function properly in a semi-auto.

Best regards,

Bruce Buck
Shotgun Report’s Technoid

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Carroll Achieves World Title as U.S. Trap Team Combines for Eight Top-15s & Two Team Titles at World Championships | USA Shooting

Source: Carroll Achieves World Title as U.S. Trap Team Combines for Eight Top-15s & Two Team Titles at World Championships | USA Shooting

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