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Is It Legal to Modify a Gun?

Yes, you can legally modify your gun — up to a point. Firearms can be modified in all kinds of ways, from how they look to how they perform, but rulings like the National Firearms Act (NFA) of 1934 impose specific regulations on some firearms. When you’re interested in changing your gun, it’s crucial to understand what’s legal and what isn’t.

While converting your gun to full auto is illegal under the NFA, not all types of modifications are banned. Learn more about what you can and cannot do to your handgun, rifle or shotgun.

Types of Gun Mods

Before you start shopping for ways you can modify your pistol or other firearm, check out some of the most common legal and illegal gun mods — and be sure to confirm their legality in your state.

Legal Gun Modifications

Thanks to the countless pieces of equipment on the market, you can easily modify your handgun or rifle to fit your shooting style and take on almost any activity. While there are many changes you can make on your own, there are some that require governmental approval, such as adding a stabilizing arm brace or installing a suppressor. These changes often require an NFA stamp and a $200 fee.

Some of the most popular types of legal modifications include:

  • Cosmetics and ergonomics: Altering the look and feel of your firearm with new sights or grips will help you create a tool that’s uniquely yours.
  • Caliber conversion: You can change your barrel or convert your chamber to accept a different caliber for improved performance in your preferred activities. Depending on the type of firearm, this may be a do-it-yourself job or require the services of a gunsmith.
  • Accurizing: Accurizing your firearm involves making usability and quality adjustments to improve its accuracy. For example, you might install an improved trigger kit or have a gunsmith recrown the barrel.

Illegal Gun Modifications

Permitted modifications often vary from state to state. For example, silencers are legal at the federal level for owners who’ve paid the tax, but some states, like New York, Illinois and New Jersey, outlaw these additions. Many state and local governments have also enacted bans on possessing firearm magazines capable of holding more than 10 rounds of ammunition. Failing to align with government and state laws could result in jail time or fines.

A few illegal gun mods you should avoid include:

  • Reducing a shotgun’s barrel to under 18 inches or its overall length to under 26 inches.
  • Cutting a rifle barrel under 16 inches or its overall length under 26 inches.
  • Converting a semi-automatic rifle to a fully automatic firearm.
  • Installing a bump stock.

Learn More at Keystone Shooting Center

Reading up on local and state laws regarding gun modifications is crucial to ensure any changes you make are legal. If you want to learn more about gun modification laws in Pennsylvania, you can count on Keystone Shooting Center to supply knowledgeable and reliable advice. We are a veteran-owned and operated business in Mars, Pennsylvania, run by talented staff ready to answer any questions you have. Contact us online or call us at (412) 357-8000 to learn more about what Keystone Shooting Center can do for you.

Great Quality! Great Selection! Great customer service! Veteran Owned! I’d highly recommend, cant see myself going anywhere else.

Nick K

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