Zaffiri Precision Zp.365Btbn 9Mm Sig P365 3.77" Black 416R S/S
The Zaffiri Precision threaded barrel for Sig P365 is a match-grade upgrade designed for shooters who want tighter groups and better reliability from their compact 9mm. Built in the USA from 416R stainless steel, this 3.77-inch drop-in replacement handles everything from lead to jacketed rounds without fuss. The black nitride finish resists corrosion and slides into your P365 without gunsmithing—just swap your factory barrel and you're shooting.
Zaffiri engineered this barrel with a fully supported chamber and improved feed ramp design that works seamlessly with your P365's lockup. The polished chamber and bore reduce friction and fouling, so your gun stays cleaner longer. At 1/10 left-hand twist with six-groove broach-cut rifling, it's optimized for 9mm ballistics and accuracy. The stress-relieved, heat-treated construction keeps the barrel stable under shooting strings, and the target crown ensures consistent performance shot after shot.
This version comes threaded 1/2 x 28 at the muzzle, so it's ready for suppressors, flash hiders, or muzzle brakes—a real advantage if you're running a can or want to tame recoil and report. A thread protector is included. The oversized lockup area and 416R steel guarantee durability, and the machined "ZP" logo is a mark of Zaffiri's quality. Whether you're dialing in a carry gun, building a suppressed P365, or just chasing better accuracy, this is the barrel that belongs in a serious P365.
Key Features
- Match-grade 416R stainless steel construction, stress-relieved and heat-treated to RC 40-42
- Drop-in fit for Sig P365—no gunsmithing required
- Threaded 1/2 x 28 muzzle with included thread protector for suppressors and muzzle devices
- Fully supported chamber and improved feed ramp design
- Polished chamber and bore for reliable performance with lead, plated, and jacketed ammunition
- Six-groove broach-cut rifling, 1/10 left-hand twist
- Target crown for shot-to-shot consistency
- Oversized lockup area for durability
- Black nitride finish for corrosion resistance
- USA manufactured
Specifications
| Brand | Zaffiri Precision |
| Firearm Compatibility | Sig Sauer P365 |
| Caliber | 9mm |
| Barrel Length | 3.77 inches |
| Material | 416R Stainless Steel |
| Finish | Black Nitride |
| Muzzle Thread | 1/2 x 28 |
| Rifling | Six-groove broach-cut |
| Twist Rate | 1/10 left-hand |
| Chamber Type | SAAMI spec, fully supported |
| Heat Treatment | RC 40-42 |
| Installation | Drop-in fit |
| Included Accessories | Thread protector |
Frequently Asked Questions
Is this barrel a true drop-in fit for my P365?
Yes. Zaffiri Precision designed this barrel as a direct drop-in replacement for the Sig P365. No fitting, hand-lapping, or gunsmithing is needed—install it and shoot.
Can I use a suppressor with this barrel?
Yes. The barrel is threaded 1/2 x 28 at the muzzle, which is the standard thread pitch for most 9mm suppressors, muzzle brakes, and flash hiders. A thread protector is included to keep the threads clean when running unsuppressed.
What ammunition works with this barrel?
The polished chamber and bore are designed to feed and function reliably with lead, plated, and jacketed 9mm ammunition. It's SAAMI spec, so any factory 9mm load is safe.
Why choose a match-grade barrel over the factory Sig barrel?
Match-grade barrels are precision-manufactured to tighter tolerances and typically feature a polished bore and fully supported chamber, which can improve accuracy and reliability. The Zaffiri also offers the flexibility of a threaded muzzle for suppressors and other muzzle devices—something the factory barrel may not.

