Functional 3D Printed Hybrid Pepperbox .22: the PG22 Maverick

U.S.A.-( Ross Peters, in Wisconsin, has created a hybrid 3D printed functional cartridge revolver, with metal components. It has been demonstrated on Youtube. The design is an interesting hybrid pepperbox, with rifled barrels.

The video gives a good explanation and documentation of this six-shot pepperbox. Peters designed the handgun to fire .22 shorts.

The barrels for the revolver are made with .22 barrel liner, which is easily available by mail order. One of the reasons to use barrel liner is it is commercially rifled. This meets the requirements for a rifled barrel, to have the firearm classified as a pistol instead of a short-barreled shotgun, in the United States.

As a historical note, the first successful cartridge revolver in the United States was chambered in .22 short. It was the Smith & Wesson No. 1. The velocity of the black powder short cartridge with the 29-grain bullet was listed as 850 feet per second in the July 19th edition of Shooting and Fishing, 1906.

The modern high velocity short cartridge lists a muzzle velocity of 1132 feet per second out of a rifle. Out of the short barrel of the PG22 Maverick, the velocity is likely comparable to the black powder cartridge out of the Smith & Wesson No. 1, which used a 3-grain black powder charge.

The .22 Short is no toy. It can easily kill large animals if the shot is placed properly. Before anesthetic, antibiotics, and modern surgical techniques, a shot to the chest or abdominal cavity with a .22 short was very likely to be fatal.

Someone who is shot with a .22 short today, in the chest cavity, who does not seek medical treatment, will probably not wake up a few days later.

Peter’s use of a ball bearing to index the hand-turned cylinder on/in the muzzle of the bottom barrel is innovative. It works as a cylinder stop. It is a simple, accurate, and cheap method, all desirable traits in a design.

The long bolt used as a cylinder pin adds tensile strength to the PLA frame.

The bolt used for an adjustable front sight was a nice touch.  The pepperbox showed usable accuracy for defensive purposes.

Because 3D printed designs are dimensionally accurate, the accuracy achieved with the ball bearing cylinder index would be very good. It is probably sufficient to use the design as the basis of a more conventional revolver with a fixed barrel in front of the cylinder.  Fixed barrel revolvers are more accurate than pepperbox revolvers. They tend to be more powerful, because the barrels can be made longer without being cumbersome.

In my experience, smooth tubing could be used for the cylinder chambers, cutting down on expense. Some nominal 8mm outside diameter / 6mm inside diameter stainless steel tubing, purchased online, did not need to be altered to chamber .22 LR. While slightly oversize, when five .22 Long Rifle cartridges were fired in a test rig, the cases bulged but did not split.

The tubing cost about $3 for 250 mm, enough to make six to nine chambers. Shipping was free. With a diligent Internet search, 5.5 mm inside diameter tubing might be located, or 5mm tubing could be drilled out to 5.5mm for tighter chambers.

For proof of principle designs, such as the one made by Ross Peters, the nominal 6mm inside diameter tubing would be sufficient. Careful safety precautions would be necessary to prevent injury.

The barrel would need to be rifled, to meet U.S. legal requirements.

Inexpensive commercial revolvers use a generous forcing cone at the back of the barrel to compensate for indexing tolerances.

Several existing designs for hybrid 3D printed revolvers have been made which index when cocked.  A rotating hammer, substituted for the striker in Peter’s design, would make such a gun more ergonomic.

A rotating hammer, connected with linkage to rotate the cylinder, would result in a revolver that would function similarly to conventional single-action designs.

Single action .22 revolvers have proved to be very practical firearms. A six to nine shot single action hybrid .22 revolver could have practical uses.

Because of the fixed barrel ahead of the cylinder, conventional revolvers tend to be accurate handguns. The same barrel liner material used by Peters for barrels in the PG22 Maverick would make a legal barrel for a more conventional design.

In the United States, the barrel must be rifled to meet the regulatory requirements of the National Firearms Act, first passed in 1934. The NFA had little useful effect in 1934, and even less today.  It is haphazardly enforced, but you do not want to be one of those chosen for enforcement.

I strongly recommend readers work to understand the law and follow it to the letter.  Playing with gun designs is a dangerous business. I am not recommending any particular design or course of action, because I have no control over any decisions made by those who choose to tinker with 3D printing.

3D hybrid designs are interesting, and legal in the United States. They have virtually no practical effect on crime. High quality .22 pistols can easily be purchased with the dollars which would be earned if the same number of hours used to make the hybrid were devoted to a minimum wage job.

The effect of hybrid designs is to show how ineffective it is to attempt to stop criminals from getting guns by restricting the legal commerce in firearms.

Reducing the legal number of guns has never worked to reduce the number of illegally owned guns. There is virtually no relationship between the two numbers.

Countries with strict restrictions on legal gun ownership have very large differences in legal gun ownership, and in homicide rates. But the number of illegal guns is often similar.

The number of guns necessary to saturate the criminal market is such a small number it can easily be supplied with black market  small shop and home manufacture.

About Dean Weingarten:Dean Weingarten

Dean Weingarten has been a peace officer, a military officer, was on the University of Wisconsin Pistol Team for four years, and was first certified to teach firearms safety in 1973. He taught the Arizona concealed carry course for fifteen years until the goal of Constitutional Carry was attained. He has degrees in meteorology and mining engineering, and retired from the Department of Defense after a 30 year career in Army Research, Development, Testing, and Evaluation.

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“Rifling the barrel to meet U.S. legal standards”? Good laws deserve to be obeyed, bad laws (particularly unconstitutional laws) deserve to be disobeyed, knowing of course that there are consequences for disobeying “the law”. Consistently obeying bad, stupid and ridiculous laws (mala prohibita) is nothing but conditioning and observing and following all laws because, “It is the law”, is blind obedience and just what the stooges in Washington want from all Americans. This country was not founded on laws, it was founded on revolution. We are not a nation of laws (despite what lawyers and politicians claim) we are a… Read more »


– Just as most people slow their car in presence of traffic cops, I’ve got nothing against being aware of the law and taking minimal steps to avoid consequences. Just keep in mind that that is what you are doing – not obeying because law is right, but avoiding consequences because it is in your interest to do so.


We agree that there are consequences for disobeying ANY law and if you’re going to do so, there is always the risk of consequences regardless of the nature of the law.


@wjd, While it’s only been eight years I’d @Jakob’s case, people do change. Most 18 year olds are not fully matured and most people do learn from their mistakes, though I prefer learning from the mistakes of others. In a just world we make allowances for people growing, maturing and learning from mistakes. Current law may not do so, but it is not necessary to continue beating on @jakob for what he sees as ancient history. Of course you may have sprung from your mother’s loins a perfect and mature person, in which cas you are harp on everyone’s… Read more »

Wild Bill

@Finnky, A leopard can not change it’s spots. This individual is one issue. The state of “the Law” is another. It does no good to mix issues.


@Jakob – Keep deluding yourself that states can override federal law, FFL stands for FEDERAL Firearms License. They follow BOTH federal and state laws. Only ways an FFL will let you walk off with a gun is if you (1] lie on 4473 Form and FBI fails or (2) you rob the FFL. Either way you’ll be committing a federal offense for which punishment can be severe. Best of luck and try not to be stupid.

People like you are huge motivation for democrats push for “universal background checks” .


“The .22 Short is no toy. It can easily kill large animals if the shot is placed properly. Before anesthetic, antibiotics, and modern surgical techniques, a shot to the chest or abdominal cavity with a .22 short was very likely to be fatal.” I hope that is no endorsement as the .22 Short, in almost anything, as a ‘defensive round?’ Defending yourself against an assault with this little guy might well render your attacker dead – eventually, ‘short’ (no pun intended) a brainpan or spinal shot. In the meantime, I don’t hold much hope for your successful defense of ‘your… Read more »


– Believe @Firewagons point was that in DGU killing your attacker is not a goal. Does you no good to fatally wound them if they kill you before succumbing to the wounds.
Generally short of contact 22 short will not penetrate a skull nor is it likely to reach spine in a frontal shot. Good luck in court if you shoot an “attacker” in the back. While this tool may be useful, it should not be anyone’s first choice (or second, or third, or…)


I’ve always butchered steers with the .22LR. But that “properly placed” phrase is the key one. In the case of instantly dropping a half a ton of herbivore, such requires PERFECT shot placement. Directly into the brain from the dead front. That isn’t hard when it’s in a corral, feeding as normal. One just waits until he lines his head up perfectly and pop the brain from 30 feet away. The fact that wild creatures won’t be so cooperative in their own demise is why we don’t use the rimfire to hunt with. Even though deer or elk (or what… Read more »

Wild Bill

That pretty much negates the GCA.


Two things, the designers name is Ross Peters, not Ralph Peters.
Second, he has never printed this gun yet in ABS plastic. Only PLA has been used by him so far.

is there a resource page where I can get started printing my own rifles? Been interested in it for awhile, however I’m not print savvy. Thnx

Wild Bill

, 18 USC Ch 44 Firearms, at 921(a)(20)(second paragraph) in pertinent part: “What constitutes a crime shall be determined in accordance with the law of the jurisdiction in which the proceedings were held…”
Let him buy all the firearms that he wants.


@Wild Bill
Hellzzz yea

Wild Bill

, How did the surfing vacation go?


@Wild Bill
Fantastic worst day was head hi biggest was around 10ft with 12 ft sets..( that’s some scary shit too my friend) 100 yds long..paddle out was around 300 yds cause of swell direction HORRIBLE JUST HORRIBLE to get outside but we got there.No one got hurt that’s what matters but some feelings got hurt along the way.By that I mean mother nature showed us who’s boss DAILY

Wild Bill

, Most cool.

Wild Bill

, I can not wait for him to tell us about it.

Wild Bill

@Yack, In the past, you have been a difficult person insulting many here. Thus, I do not care what you think or do.
I do care about your misstatements of law that might deceive others. If you really believed what you write here you would have made a purchase, already. You have not.
You are either trolling for responses for which you are paid or an fed agent looking for someone to be the subject of your next easy case. So, I’ll not respond directly to you.


That’s how I deal with them. I prefer to talk ABOUT the trolls, rather than TO them. This way we still get to correct their eternal spew of Bravo Sierra, and they cannot do anything about it since we ignore them like the miscreants that they are!


Will, I second that. This is kind of like a Doonesbury strip.

Wild Bill

, Apparently this fellow has not heard of the American system of Dual Sovereigny. If state law could “override” federal law, then the states would “override” every act of Congress.
I look forward to reading about his attempt to push his theory.