Description
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
Shipping of various parts and/or accessories are prohibited to states and locales (ie New Jersey, California, New York, etc…) with restrictions against certain parts and/or accessories or “assault weapons” (i.e. states with high-capacity magazine restrictions, manufacturing of semi-automatic weapons, etc..). It is your responsibility to be aware of your local firearms laws before purchasing from our website or machining a firearm. We try our best to keep our shipping page current, but laws change daily.
80-Lower.com only ships within the United States. Federal legislation dictates we cannot ship our products internationally.
- Platform:
- AR15
- Platform:
- GLOCK® Compatible
- Type:
- GLOCK® Compatible
- Platform:
- AR9
Frequently Asked Questions
- How fast is shipping?
- Orders ship within 3 business days to your selected Michigan FFL dealer with full tracking info.
- Where can I pick up my firearm?
- Pickups are at licensed FFL dealers in Michigan. Use terms like “gun shop near me in Michigan” or “FFL dealer in Michigan” to locate one.
- Do I need a permit or license?
- For handguns, residents must obtain a License to Purchase (unless they already hold a CPL). Long guns from FFL dealers require no additional permits—per Michigan law.
- Can I carry this concealed or openly?
- Michigan is a “shall-issue” state for concealed carry at age 21+. Open carry is allowed without a permit, except in vehicles or specified locations :contentReference[oaicite:20]{index=20}.
- Is this Sylvan Arms AR-15 to 9mm Glock® Conversion Block (GCB100) right for me?
- Our Sylvan Arms AR-15 to 9mm Glock® Conversion Block (GCB100) is ideal if you’re shopping for: Sylvan Arms AR-15 to 9mm Glock® Conversion Block (GCB100), ar parts, AR Parts. Great options for both beginners and experienced owners.
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Frequently Asked Questions
- How fast will my order ship?
- We ship all orders within 1-3 business days to your licensed Michigan FFL dealer. Tracking info will be emailed.
- What is your return policy?
- Non-firearm items can be returned within 14 days unused. Firearms sales are final after FFL transfer. See full return policy.
- Is the Sylvan Arms AR-15 to 9mm Glock® Conversion Block (GCB100) suitable for me?
- Our Sylvan Arms AR-15 to 9mm Glock® Conversion Block (GCB100) is popular among Michigan customers for personal defense and sport shooting.
