Shooting 40 Super with Glock 21

Ammo Test uses a Glock 21 with Lonewolf 45-40S conversion barrel. He is shooting 40 super. It is a .450 winmag case trimmed down to 10mm length and necked down to 40 cal. Rather impressive velocities. Upwards of 1700 fps.

Nicholas C

Co-Founder of KRISSTALK forums, an owner’s support group and all things KRISS Vector related. Nick found his passion through competitive shooting while living in NY. He participates in USPSA and 3Gun. He loves all things that shoots and flashlights. Really really bright flashlights.

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  • Casey

    holy crap that 220 hard cast looks ridiculous. remind me to never piss that guy off.

  • Ken

    I think a more appropriate name would have been 10mm something, not .40 something.

  • Rabobo

    Couldn’t you just shoot this out of a glock 20 with a barrel swap?

    • No, the .40 Super’s case rim is too fat for the Glock 20’s breechface. Remember, the .40 Super’s case rim is the same size as a .45 ACP.

  • Sean

    What is the point? That is more powerful than 10mm, but not by that much. And I have never seen .40 super ammo ever.

  • Mike

    Why shoot .40 super when you can shoot .460 Rowland? Besides, if you convert your G21 to .460 Rowland, you can still shoot .45 ACP and .45 Super.

    • If you convert a Glock 21 to .40 Super, you can still shoot .45 ACP and .45 Super by reinstalling the original G21 barrel.

      Speaking of the .460 Rowland, anybody remember when Johnny Rowland was going to offer his own version of the .40 Super: the oddly named .464 Rowland?