H&K USP9 Tactical Threaded Barrel – 9mm, 4.56", M13.5x1 LH

A genuine factory Heckler & Koch threaded barrel for the USP9 Tactical, in 9mm, 4.56 inches, threaded M13.5x1 left-hand. This is HK's own barrel with the polygonal bore profile the USP platform is built around — not an aftermarket blank cut to approximate it. HK part number 226352.

Know the Thread Before You Order

The USP Tactical barrels use metric, left-hand threads, and each caliber uses a different pitch. The 9mm barrel is M13.5x1 LH — not 1/2x28, not .578x28, and not the M16x1 LH used on the .45. If you are buying a suppressor or a muzzle device for this barrel, confirm it is cut for M13.5x1 left-hand or plan on a thread adapter.

Polygonal Bore

HK describes the USP Tactical as having a "threaded O-ring barrel with polygonal bore profile," and HK's USP manual notes the barrels are cold hammer-forged. Polygonal rifling uses rounded lands and grooves rather than sharp-cornered conventional rifling, producing a better gas seal, less bullet deformation, and easier cleaning — and it's been a defining HK feature since the platform launched.

Specifications

Frequently Asked Questions

What thread pitch is this?

M13.5x1 left-hand — a metric, reverse-cut thread. Retailer listings claiming 1/2x28 for this part are incorrect.

Will it fit a standard USP9 or a USP9 Expert?

HK lists this barrel only under USP Tactical accessories and publishes no cross-fitment. 

Does a thread protector come with it?

HK sells the thread cap as a separate part (207330). Contact us if you need one.

Does it include an O-ring?

It does not include an o-ring.