Making the World’s Best Pistol Barrels (Video)

Authors Gunsmithing Matt Kartozian

Estimated reading time: 10 minutes

Bar-Sto Precision Machine has been making pistol barrels since 1967.  They are considered by many, myself included, to be the best pistol barrels on the planet. 

Bar-Sto Beginnings

The company was started by Irv III’s dad, Irv Stone Jr., when he made the first 50 barrels out of leftover material he had machined for the Apollo Space Program rocket. See the video at the bottom for the full Apollo story. 

Irv III started working in the shop in his early teens and intimately knows every step of the barrel-making process.  On top of that, Irv started competing in pistol matches before USPSA was formed.  He competed against the biggest names in the sport, Leatham, Koenig, Enos, Barnhart, and all the other superstar shooters of the early days of what became USPSA, IPSC, and IDPA.  As a competitor, he learned firsthand what did and did not work in the barrel world.  40 years later it’s safe to say that Irv knows what it takes to make the best barrel.

My History

I started using Bar-Sto barrels around 2000 and shortly after that, they were the only barrels I would use in my shop for Custom Glock builds.  While on vacation this Summer I had to chance to meet up with owner Irv Stone III and his crew at their shop in Sturgis, SD.

Bar-Sto Barrels: How They’re Made

All Bar-Sto barrels start when raw bar stock steel comes into the shop.  The bar stock is chopped up and those pieces are then machined into a barrel blank.  One blank can make any barrel in Bar-Sto’s large catalog.  The only part of making the barrel not done in-house is when these blanks are sent out for heat treating and magnafluxing.

Heat treating hardens the steel making it stronger and more resistant to wear.  Magnafluxing is a process many of you have probably not heard of.  It uses magnetic fields to find flaws; microscopic imperfections or cracks in metal.  It is used in many industries, race car suspension parts are often “magged” between races as part of the prep process for example.  For Bar-Sto it is a way to ensure there are no flaws in the barrel blank before machining begins.

Many gun companies heat treat their parts after machining, so I was surprised to learn that Bar-Sto heat treats as the first step.  I asked Irv, does that tear up and wear out your tooling faster?  “Yes, it does wear out tooling faster but it makes a better barrel,” Irv told me.  “Also when you heat treat first, every cut you make on that barrel relieves stress in the metal.  By the time our barrels are finished there is no stress left in the barrel.  The other reason is that when you heat material it wants to move.  When it is heat treated first we are not adding heat when we machine it, so they stay straight and don’t move.”

Absolute Quality

Many barrels on the market, some hyped by Influencers, are purchased in bulk; then the “manufacturer” adds goofy flutes or flashy coatings.  Bar-sto is the opposite of that kind of barrel.

Bar-Sto barrels are all made in-house in Sturgis, SD.  Many of the steps in making the barrels involve human craftsman and manual machine operations because it makes a better barrel.  The total time to complete all the steps of a barrel from treated blank to the finished barrel is about 40 minutes, quality takes time.

Once the blanks come back from heat treatment and getting magged they are put into the gundrill machine.  Various barrels that require more or less material go on top of or below the chamber.  This is done by varying the height of the blank in the drill.  The drilling process is slow as well.  About 10 minutes for a 4-inch barrel and 15-20 minutes for a 6.0 inch.

Once drilled they go to the honing machine.  Honing is done in two steps to ensure a super smooth barrel interior.  After honing they are machined for the outside diameter of the barrel, bull, bushing, etc.  Another process creates the locking lugs and hoods and the exterior dimensions of the chamber.  Chambers are cut to minimum SAAMI spec.  This creates a very tight chamber which aids in accuracy but if you load your ammo long it could be a problem.  The easy fix is to send a few of your loaded rounds to Bar-Sto when you order a barrel and Irv will personally chamber the barrel to your ammo at no additional cost.  See the video below for more information on ammo.

The final machining process is to create rifling inside the barrel.  Bar-Sto uses a broach cutter from the 1930s and it is super cool to watch.  The broacher is tall and large.  The operator stands on a platform about 7 feet up at the top of the machine.  The smoothbore barrel is placed in the machine and it is spun as a long broach cuts the rifling into the barrel.  All of this is done while it is submerged in black oil.

The Final Step

The final step is polishing the exterior of the barrel and inspecting to make sure it is perfect.  Even after inspection, the barrels are checked one final time as they are packaged for shipping.  While I was there Irv’s wife Lisa was checking barrels with a caliper before they were shipped out.

If you are in the market for a custom-built pistol, you should consider Bar-Sto.  Irv was Pistolsmith of the Year in 2016 and his custom builds are considerably less expensive than other big-name shops and as good, or in my opinion actually better.

Bar-Sto barrels are available for a ton of pistols.  Glock, CZ, all 1911s, XD, Hi-Power, Beretta, S&W revos and autos, Sig, and more.  They are available in Match Target which will require fitting or Semi Fit which can go either way, but I think Match Target is the way to go to get the most out of your pistol.

If you are going to spend your hard-earned money on a new pistol barrel, you owe it to yourself to give Bar-Sto a look.  They are a family-owned company making the best barrels on the market with outstanding service and support.

Bar-Sto Precision Machine


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  • Thomas Heffernan October 24, 2023, 6:05 am

    I am having trouble with two pistol barrels. On both the ammo does not seat in the chamber. One is a Springfield EMP 9mm.
    The other is a CZ remi 9mm. I have contacted both gun companies to get help. If that does not work out, I would be interested in
    ordering new barrels from your company.

    Please advise

  • Todd October 23, 2023, 10:42 am

    Why show the destroyed 10mm and then not elaborate on it.

    It almost comes across badly for BarSto even if it was “deliberate”.

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