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Gunsmith Services & Terminology

In Blog by Rich2 Comments

Lots of people want to know how to get the most out of their rifles. It’s pretty natural, what kind of gunsmith services are worth the cost and effort? Why is some of the terminology so confusing? We’re going to talk about different gunsmith services and terminology in this post. The idea is to better educate everybody so they have a good grasp of what the different gunsmith services are and what the terminology means. Then you can evaluate which gunsmith services are most likely to improve the accuracy of your rifle and which are more about looking cool! We all work hard for our money, so knowing how to spend it when it comes to gunsmith services is beneficial.

Gunsmith Services

I’m going to attempt to describe some of the services offered by various Gunsmith shops and which of the gunsmith services tend to be most beneficial. Hopefully this will help clear the air a bit so somebody who’s considering having a rifle worked on has a reasonable idea where to start. The quality of the Gunsmith is every bit as important as the service. You can have a top shop offer the same service as a local operation that’s a lot smaller but depending who’s doing the work the pricing and quality of the work can vary greatly. Doing some research on which shop you plan to use is an important step, don’t neglect it. I’m also going to point out that I’m not a Gunsmith, so this is based on my experience and understanding of the terms.

  • Action Truing – This refers to a combination of several other services with the intended result being to remove any inconsistencies in the manufacturing of the rifle’s action. It typically involves the following:
    • Squaring the Receiver Face – The receiver is put in a lathe and the face of the receiver, that the barrel mates up against, is re-cut so that it is perpendicular to the action raceway where the bolt sits when closed. The idea here is to have the barrel mounted perfectly straight and in line with the action body and the bolt. You don’t want the barrel pointing left, up, down, to the right, anything but straight ahead!
      • phoenix-custom-rifles-6

        You can see bare metal where the face of the receiver was re-cut!

    • Cutting and/or Lapping Bolt Lugs – This involves re-cutting or using a lapping compound (it’s like sand paper paste) to ensure the lugs on the end of the bolt are cut straight. Lapping the lugs ensures that any high spots on the lugs on the bolt or the lugs in the receiver are worn down so the lugs make good, even contact, across the surfaces that interact.
    • Squaring the Bolt Face – This is just like squaring the face of the receiver. The bolt is dialed into a lathe so that it is set up to spin as close to perfectly concentric as possible. The face of the bolt, that mates up against the breech, is then re-cut so that it is perfectly flat and even.
      • Gunsmith services-bolt face truing

        Here you can see bare metal on the face of the bolt, the outer diameter of the bolt face, and the lugs, where work was done to ensure proper alignment

    • Re-Cutting Receiver Threads – This can be one of the largest manufacturing inconsistencies. The action has threads inside it where the barrel screws into the front of the action. You want those threads cut pefectly square and concentric with the raceway where the bolt sits so the cartridge is pushed straight into the action. If these threads are not concentric, the barrel isn’t mounted square. Then you’re pushing rounds into the chamber at an angle. No good.
      • phoenix-custom-rifles-7

        These threads were cleaned up, but not re-cut. Typically the thread pitch changes when the threads are re-cut to correct thread alignment. This means the factory barrel with the original thread pitch won’t work anymore.

  • Bolt Knob Upgrade – This is a pretty popular Remington modification. There are a few ways of doing it. Some Gunsmiths will grind and turn down the existing bolt knob and thread it for a larger knob to be screwed on. The advantage is more leverage and easier bolt manipulation. However, this can often expose voids in the Remington knobs because they are cast. Another approach is to cut off the old knob, drill and tap a hole, then install a threaded stud which you screw the new knob onto.
    • phoenix-custom-rifles-2

      Here you can see a non-factory bolt knob that was added after the original was removed, and a threaded stud was installed!

  • Bushing the Firing Pin Hole – This is pretty neat. The Gunsmith will actually drill out the face of the bolt. Install a new bushing that has a smaller diameter hole for the firing pin into it. Then everything will be brazed/welded into place and the bolt face evened out. The idea is to set up the bolt for a smaller firing pin for use will small rifle primers. Using a large pin with a small primer can often cause issues with the primers ‘blanking’ or failing to fire. A small pin can still be used with a large primer without issue. Really this is only a concern if you have an action and bolt set up for large rifle primers and you want to use it with small rifle primers.
  • Bolt and/or Barrel Fluting – This really has more to do with appearance than function. You can save some weight on a barrel by fluting it but I doubt it’s going to be enough to change your life or give you any kind of edge. In theory, by fluting the bolt you give dirt and grime a place to migrate to instead of gumming up your action. However, I think the advantage gained is more in appearance than actual functional benefit.
    • lube-bolt

      This is mainly cosmetic, but it does add some flare to your rifle!

  • Muzzle Threading – Self explanatory. Cutting threads onto the exterior of the muzzle to facilitate the installation of a muzzle brake, flash hider, or suppressor. One need only shoot a rifle with a brake to see the advantage gained in recoil reduction. Suppressors are also a blast to shoot with. Of the services you can get, this tends to be pretty affordable and largely beneficial.
  • Chambering a Barrel – This is the process of taking a barrel blank, and cutting threads on the exterior so that it threads into the receiver. Additionally a special cutting tool, called a reamer, is used to cut the shape of the cartridge chamber into the receiver end of the barrel. There are different reamers for different calibers and even different projectiles within the same caliber. If you aren’t sure about what to ask for, ask the Gunsmith. One of their jobs is to understand what you want to do and giving you options to best achieve your goal!
  • Bedding an Action – Here you have the gunsmith using a hard curing liquid between the action of your rifle and the stock. The idea is to make a mold of your action, that hardens and becomes part of the stock, so the action is fully supported and a perfect fit for that stock. This is not necessary, but sometimes still done even with stocks that have aluminum bedding blocks designed for “bolt in and go” operation.
    • bed-your-stock-LRI2

      Bedding Job from Long Rifles Inc., whom I believe have the best looking bedding jobs ever…

Wrapping Up

So this post wound up reading a lot like a glossary of Gunsmith Services and Terminology, that wasn’t really my objective. I do hope that it may help some newer shooters gain some insight as to what the different gunsmith services are and how they alter or upgrade the rifle they are performed upon. I’ll say this much. In my experience, a quality match grade barrel, that was chambered by a competent gunsmith is probably the largest factor that contributes to an accurate gun.

Spend your money on the barrel and the chambering job first. It seems to have the greatest impact on the rifle’s performance. Beyond that, I would true the action. Things like fluting of barrels and bolts, and threading of muzzles are nice additions, but not necessary to achieve maximum accuracy. Like all things in life, your intended purpose will dictate which modifications are necessary. If you have any questions about this, or a comment to add, please do so below!

Owner and Proprietor of AccuracyTech, LLC. Rich is a Firearms Enthusiast, Precision Rifle Competitor, and Writer. He is committed to bringing readers quality reviews and articles related to the Precision Shooting Sports. If you have any questions for him, please use the contact form on the site.

Comments

  1. I recently acquired a CZ550fs chambered in 9.3×62 Mauser. I haven’t fired yet but a love the thing already and have considered this little gun with a bit more thunder. The 9.3x 64 Breaneke that has enough case capacity to squeeze in another 10gr of powder and push a 285 gr bullet to 4k pounds of energy. (REF; ammoguide.com) Which I don’t consider a bad thing.
    Shops generally discuss what they can do for a Mod 700 Remington but none discuss the safari type rifles too much. I am curious If you wish to take on a re-chamber and bolt face rework on this rifle?
    I’ll be out till Monday.

    1. Author

      We don’t do gunsmithing work, Michael, I’d recommend you contact Chad at Long Rifles Inc.

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