Redesigned 40mm UBGL from Fabrykę Broni

The Polish firearms company Fabrykę Broni has brought their redesigned 40x46mm Low Velocity Under Barrel Grenade Launcher to the public. The company had a previous 40mm UBGL that incorporated a slanted grip with the trigger almost underneath the muzzle of the grenade launcher (this looks like it allows a significant reduction in weight). With this redesign, the company has placed the trigger inline with the barrel, directly in front of the magazine, very similar to Russian GP30 grenade launchers. It appears that the grenade launcher does not require a proprietary handguard to be mounted to the 5.56x45mm MSBS rifle (example shown with 7.62x39mm MSBS).

gp-msbs02 gp-msbs01

Similar to the previous launcher, the tube is opened to the left, allowing the use of longer 40mm grenades to be chambered, in addition to standard ones. The safety is on the right side, and the barrel latch on the left, facilitating a quick release. Sights are on a picatinny mounted rotating quadrant rail on the left side, mounted to the handguard of the MSBS. Theoretically this should allow the same sights to be mounted on the right side for left handed users, but I couldn’t find anything that confirms this. The entire package appears to be a very compact design, is probably one of the shorter of all the current issue 40x46mm grenade launchers on the international market.

Previous design

i-i12-08-93kbk3 msbs-556_article_pleine_colonne


Infantry Marine, based in the Midwest. Specifically interested in small arms history, development, and usage within the MENA region and Central Asia. To that end, I run Silah Report, a website dedicated to analyzing small arms history and news out of MENA and Central Asia.

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  • Tom-UK

    How much is 40mm affected by barrel length? Does an extra inch add much velocity and is there any appreciable impact to the user in ease of shooting?

    • Major Tom

      It is affected by length, but you’re still arcing a grenade on target at all but the shortest of ranges. Even if you doubled the length of say the M203’s barrel, it won’t magically turn a rainbow-shooter into a flat fastball.

    • LazyReader

      You’re arcing a grenade like a mortar. There are two m203 lengths 9 inch and 12 inch so 3 inches is not that great a difference when the kill radius of the round is 5 meters and wound radius of 60 meters or more

    • Iggy

      You can find pictures of a sawn-off M79 ‘pistol’ online which was developed for special forces in Vietnam, they reported no major issues in terms of range/accuracy.

  • LazyReader

    If Crye’s making an under barrel shotgun they can make a 40mm

  • Hokum

    Well, perhaps they should finally release the rifle itself prior to grenade launcher? When?!