Can I Modify My Firearm?

Michigan law does not prohibit the modification of a firearm. Common firearm modifications include replacing or modifying:

  • Grips including pistol grips;
  • Triggers including differing pull settings;
  • Stocks including folding stocks;
  • Sights including scopes, dot sights, glowing or night sights, and laser sights;
  • Camouflaging; and
  • Barrels including rifled slug barrels and barrels with adjustable chokes.

However, certain firearm modifications are criminal in Michigan.

Machine Gun, Silencer, Short (Sawed-Off) Barrel

Under Michigan law, the manufacture, sale, offer for sale, or possession of a firearm with any of the following modifications can result in felony criminal charges punishable by up to 5 years imprisonment, or a fine of up to $2,500.00, or both:

  • Machine gun, which is defined as a firearm that shoots or is designed to shoot automatically more than 1 shot without manual reloading by a single function of the trigger. MCL 750.224.
  • Muffler or silencer, which is defined as a device for muffling, silencing, or deadening the report of a firearm. This also includes a part or a combination of parts intended for assembling or fabricating a muffler or silencer. MCL 750.224.
  • Gas gun, which is defined as a device, weapon, cartridge, container, or contrivance designed to render a person temporarily or permanently disabled by the ejection, release, or emission of a gas or other substance. MCL 750.224.
  • Short-barreled (sawed-off) shotgun, which is defined as a shotgun having 1 or more barrels less than 18 inches in length or a weapon made from a shotgun, whether by alteration, modification, or otherwise, if the weapon as modified has an overall length of less than 26 inches. MCL 750.224b.
  • Short-barreled (sawed-off) rifle, which is defined as a rifle having 1 or more barrels less than 16 inches in length or a weapon made from a rifle, whether by alteration, modification, or otherwise, if the weapon as modified has an overall length of less than 26 inches. MCL 750.224b.

Semi-Automatic to Automatic Conversion

Under Michigan law, the manufacture, sale, distribution, or possession, or an attempt to do so, of a device that is designed or intended to be used to convert a semiautomatic firearm into a fully automatic firearm is a felony punishable by up to 4 years imprisonment, or a fine of up to $2,000.00, or both. And, demonstrating or attempting to demonstrate to another person how to manufacture or install a device to convert a semiautomatic firearm into a fully automatic firearm is a felony that carries the same penalty. MCL 750.224e.

Altering or Removing Markings or Numbers

Michigan law provides that a person who alters, removes, or obliterates the name of the maker, model, manufacturer’s number, or other mark of identity of a pistol or other firearm is guilty of a felony punishable by up to 2 years imprisonment or a fine of up to $1,000.00. Even possessing a firearm with altered, removed, or obliterated markings or numbers is presumptive evidence that the possessor is the person who did the altering, removing, or obliterating. MCL 750.230.

Spring Guns or Traps

Michigan law prohibits setting spring guns or traps that operate like a firearm with gunpowder or other explosives. Setting a spring gun or a trap that operates like a firearm is a misdemeanor punishable by up to 1 year in jail or a fine of up to $500.00. If a spring gun or trap that operates like a firearm results in killing a person, the crime is manslaughter. MCL 750.236.

Computer-Assisted Shooting

Michigan law prohibits computer-assisted shooting, which is defined as the use of a computer or any other device, equipment, or software to remotely control the aiming or discharge of a firearm. Computer-assisted shooting is a misdemeanor punishable by up to 93 days jail, or a fine of up to $500.00, or both. MCL 750.236a, MCL 750.236b, and MCL 750.236c.

Police will quickly arrest persons possessing illegally-modified firearms, and police are quite adept at identifying illegal modifications. Police also have tools to test and inspect firearms. One such tool is a red and white stick that is inserted into the barrel to test the barrel length. If the barrel is too short, the red part of the stick will extend beyond the muzzle.

I have modified several of my own firearms including the modification of barrels, grips, and sights. However, I wouldn’t undertake more complicated modifications without assistance. Some modifications shouldn’t be undertaken unless you are trained and qualified as an armorer. Some firearms modifications can weaken a firearm, damage a firearm, or cause a firearm to malfunction, which can involve devastating consequences—like the death of the shooter when the gun malfunctions. Most firearms modifications will also void any manufacturer’s warranty on the firearm.

Jeff and Kymberly Schroder are criminal defense attorneys with more than 28 years combined experience in handling crimes involving firearms. Both Kymberly and I are proud firearms enthusiasts, and I am a member of the National Rifle Association and the Kalamazoo Rod and Gun Club. If you have questions about your firearms rights or Michigan’s firearms laws, or if you have been charged with a civil infraction or a crime involving a firearm, we will be more than happy to speak with you about your question or your case.

Jeffrey M. Schroder

photo by I, Bluedog

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