LMT Piston Spring

Manufactured by Lewis Machine & Tool
SKU: 10435
MPN: 10435
Manufactured by Lewis Machine & Tool
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Due to the overwhelming response to our Black Friday and Cyber Monday sales, we are working hard to catch up! New orders of non-FFL items will ship within 3 business days (M-F), and FFL orders will ship within 8 business days if transfer details are provided.

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Originally, the AR15 was designed to be a direct gas impingement system. That is to say that, after you fire a round, some of the gas is diverted from the barrel and backwards into a gas tube. Then, that gas itself forces the bolt back so that it can eject the spent cartridge and make room for the next round to come into the chamber. Another system, that used in the AK47, works a little bit differently. A gas piston design starts the same way: gas is bled off from the barrel. Then, in this system, the gas pushes on a piston and the piston actuates the bolt. There are some advantages to this kind of system, called a gas piston design. First and foremost, it keeps the chamber much cleaner. Anyone with a direct gas AR will tell you that after a few rounds, it looks like you stored the rifle in a coal mine. Whereas if you look inside of an AK, you’ll see much less carbon for the same number of rounds. But, there’s a bit of added complexity in a piston driven design. Once that piston has acted on the bolt, it needs to be returned forward so that the firearm can continue to cycle. In those cases, you’ll need one of these LMT Piston Springs. Basically this little spring is what keeps the gun running, so you’d do well to pick up a few and replace them often. The LMT Piston Spring is what you need to keep your piston driven AR running smoothly, and these should be replaced relatively often assuming you don’t want to run your AR as a bolt action.

  • Piston Spring
  • For Piston Drivm ARs
  • Replace Semi-Annually or sooner for best performance 

Lewis Machine and Tool Company has been providing US Military, law enforcement, and government agencies with high-quality weapon systems since 1980. LMT is dedicated to providing that same level of precision engineering to civilians as well and is even expanding into foreign military services. All LMT Defense products are 100% made in America and they are a qualified 2005 GSA supplier. Lewis Machine & Tool has also won many awards for their quality engineering and excellence in business.
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BrandLewis Machine & Tool
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.

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