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

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The AR-15 is one of the world's most versatile rifle platforms. Take it a step further and give your AR the ability to switch even the caliber it fires. No, I'm not talking about switching from .223 to 5.56mm or even 5.56mm to .300BLK. I'm talking about 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 BCG, you can use the entire bottom half of your current AR-15 to bolt on all that stuff.

What makes it all work though is the Sylvan Arms GCB100. It's an AR-15 to 9mm Glock® 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.

Additional Info:

  • CNC'd from 6061-T6 billet aluminum
  • Works with Glock® 17 and Glock® 19 mags
  • Does not induce "last round bolt open" (LRBO)

DISCLAIMER: “GLOCK” is a federally registered trademark of GLOCK, Inc. and is one of many trademarks owned by GLOCK, Inc. and GLOCK Ges.m.b.H. Neither 80 Percent Lowers, a/k/a 80-lower.com nor this site are affiliated in any manner with, or otherwise endorsed by, GLOCK, Inc. or GLOCK Ges.m.b.H. The use of “GLOCK” on this page is merely to advertise the sale of GLOCK pistols, parts, or components. For additional genuine GLOCK, Inc. and GLOCK Ges.m.b.H products and parts visit www.glock.com. 

WARNING: Handling firearms parts and accessories can expose you to lead and other petroleum products 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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GLOCK® Compatible
GLOCK® Compatible

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