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Sylvan Arms AR-15 to 9mm Glock® Conversion Block (GCB100)

Usually ships the same day or the next business day!

The AR-15 is one of the world's most versatile rifle platforms. Kick it up a notch and give your AR the ability to switch even the caliber it fires. No, I don't mean switching from .223 to 5.56mm or even 5.56mm to .300BLK. I mean the ability to switch from one of those calibers to 9mm. Yup, it can be done. Once you've acquired the right upper assembly and corresponding BCG, you can use the entire bottom half of your current AR-15 to bolt on all that stuff.

What brings it all together though is the Sylvan Arms GCB100. It's a conversion block for your AR's mag well. It turns that big 5.56mm-sized hole into a 9mm-sized one that will accept Glock® mags loaded with your favorite 9mm ammo. See below for more details.

Additional Info:

  • Works with Glock® 17 and Glock® 19 mags
  • Built of 6061 aircraft grade aluminum
  • Does not include last round bolt hold open

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GLOCK® Compatible

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