Alpha Shooting Sports Marksman V4 Optics Ready Slide for GLOCK 21 Gen3

1 Review

In Stock

Standard orders will ship out in 1 business day (M-F) if ordered by 3:30 pm CST. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination. NFA items will take longer to ship and are dependent upon ATF processing times.

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If you have a G21 Gen3 Glock and finally decide to upgrade to an RMR optic, then check out this Marksman 45 ACP version 4 optics-ready slide from Alpha Shooting Sports. The slide comes with an RMR cut to a depth of .125 inches and includes an RMR cap to keep the internals of your G21 Gen3 Glock free from debris until you can choose the perfect optic solution for you. Alpha Shooting Sports heavily serrates the Marksman V4 slide with sixty-degree hash marks to ensure positive control and loading action regardless of the weather conditions.

  • Slide Cut: Optic Ready Trijicon RMR and Holosun 507
  • Finish: PVD DLC Coating
  • Caliber: 45 ACP
  • Compatible: Gen 3 G21

In addition, Alpha Shooting Sports includes a pair of front alignment posts on the RMR cut for the exact placement of your optic system. This Marksman V4 slide features skeletonized pockets to enhance aesthetics and lower the weight as much as possible while still giving you responsive and consistently dependable slide action. As with all the company's excellent products, this Marksman V4 optics-ready RMR Trijicon cut optic-ready slide from Alpha Shooting Sports for the G21 Gen3 Glock is made in the U.S. and features a limited lifetime warranty.

With over fifteen years of providing avid firearm enthusiasts superior performing, high-quality AR15 solutions, Alpha Shooting Sports is the source to turn to when seeking the right Glock compatible or AR15 parts and accessories. Whether you're seeking to upgrade your Glock 21 Gen3 for a three-gun competition or simply insist on shooting with the highest accuracy at the range you can get, you can count on Alpha Shooting Sports to give you the edge you need.
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BrandAlpha Shooting Sports
MaterialSteel - 416 Stainless
Optic TypeMultiple - See Description
PlatformGlock Handguns
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

Ratings & Reviews

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Great Slide

by -

Took about 3 days for my order to arrive. Went out shooting the next day and shot about 500 rounds from this slide with no mishaps. I was gifted their TiN barrel, so I figured I'd go with their slide. They worked very well together. I'm excited for my next range day.