AR-15 Bolt Carrier Bounce

Steve Johnson
by Steve Johnson

Andrew from Vuurwapen Blog has created this slow motion video demonstrating AR-15 bolt carrier bounce. It shows how lighter weight buffers allow the bolt carrier to bounce back after hitting the barrel extension.

The weight of the buffer becomes critical when said items begin to reach the end of their lifespan (or were never satisfactory to begin with), or when the weapon has been fired for thousands of rounds without any lubrication, or when various types of ammunition are used.

I highly recommend reading Andrew’s blog post.

[ Many thanks to jdun1911 for emailing me the link. ]

Steve Johnson
Steve Johnson

I founded TFB in 2007 and over 10 years worked tirelessly, with the help of my team, to build it up into the largest gun blog online. I retired as Editor in Chief in 2017. During my decade at TFB I was fortunate to work with the most amazing talented writers and genuinely good people!

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  • Jdun1911 Jdun1911 on Aug 03, 2010

    For those that are interested in upgrading to H Buffer and extra power springs and wants to know where to get them.

    I have bought from all of the shop listed below.

    Springs. Make sure you know the difference between rifle (non-collapsible stock) and carbine (collapsible stock).

    http://www.gunsprings.com/i...

    or

    http://www.sprinco.com/tact...

    Buffer

    http://www.bravocompanyusa....

  • Redchrome Redchrome on Aug 09, 2010

    As for why the 9mm buffer bounced when lighter ones didn't; it's because the 9mm buffer is solid and does not have separate weights inside it. The sliding weights act like a dead-blow hammer to reduce bolt bounce.

    Notably, the rifle buffer didn't seem to bounce much with any ammo. Note that the rifle buffer has 5 (steel) weights inside it, unlike the stock 'carbine' buffer that has only 3.

    The stock buffers use rubber bumpers between them, so they can move a *little* bit when the buffer impacts something. I would like to see a comparison with the MGI rate-reducing buffer which AFAIK uses a spring between the body and the weight, so more movement should be available.

    http://www.mgimilitary.com/...

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