Sale
FAXON DUTY SERIES THREADED BARREL FOR P365 9MM
Faxon
$97.00
Description
Faxon Firearms — Pistol Barrels — For SIG®
FAXON DUTY SERIES THREADED BARREL FOR SIG® P365 9MM — NITRIDE / 365A910NFNOQ-T
SIG® P365
9mm
Duty Series
4150 CMV Steel
Threaded 1/2×28
Nitride In & Out
Drop-In
Suppressor Ready
Made in Ohio
No FFL Required
The Faxon Duty Series Threaded Barrel for SIG® P365 (365A910NFNOQ-T) is a drop-in replacement barrel machined from stress-relieved 4150 CMV steel and salt bath nitrided inside and out. At 3.71” with a threaded 1/2×28 muzzle, it adds suppressor and compensator capability to the P365 platform without altering the slim profile of the slide. Conventional 1:10 button rifling ensures compatibility with the full range of 9mm ammunition, including cast lead. Tighter-than-OEM tolerances improve lockup without requiring gunsmithing. Ships direct — no FFL transfer needed.
Not a Firearm — Ships Direct, No FFL Required
This is a pistol barrel component, not a serialized firearm. Ships directly to your door with no FFL dealer transfer. Verify local laws before ordering.
Installation Note — O-Ring Removal May Be Required
Due to the slim profile of the SIG® P365 slide, you may need to remove the O-ring from the barrel to install it in your slide. This is normal for this platform and does not affect function. Remove the O-ring, seat the barrel, confirm fit, then reinstall the O-ring if clearance allows.
Duty Series — 4150 CMV, Built for Hard Use
4150 CMV Steel — Duty-Grade Material
The Duty Series uses stress-relieved 4150 Chrome Moly Vanadium steel throughout — the same material specification used in military-pattern rifle barrels. 4150 CMV is harder and more wear-resistant than standard 4140 steel, and the stress-relieving process reduces internal tension for dimensional stability under sustained fire. Every Duty Series barrel is air-gauge tested and headspace checked before leaving the Ohio facility.
Salt Bath Nitride — Inside and Out
The entire barrel — bore, exterior, and chamber — receives a full salt bath nitride treatment. Nitride increases surface hardness significantly over bare steel, dramatically improves corrosion resistance, and reduces friction across the bore surface. Unlike coatings that sit on top of the metal, nitride diffuses into the steel, so it cannot chip, flake, or wear away from the bore under normal use. The result is a barrel that cleans faster, resists rust, and holds up to sustained hard use.
Threaded Muzzle — Suppressor & Compensator Ready
The 1/2×28 threaded muzzle is the standard thread pitch for 9mm suppressors and compensators. Attach a 9mm direct-thread suppressor or compensator directly to the barrel without an adapter. Running the P365 suppressed with this barrel requires a taller sight set to clear the suppressor body — standard P365 sights will be blocked. Thread protector recommended when running without a muzzle device to protect the threads during carry.
Conventional Rifling — Full Ammo Compatibility
The Duty Series barrel uses conventional button rifling with a 1:10 right-hand twist. Conventional rifling — as distinct from polygonal rifling used in OEM SIG and Glock barrels — engages the bullet with traditional land-and-groove geometry that is safe for use with cast lead ammunition. This opens the full range of 9mm ammunition types including cast lead plinking loads, standard FMJ, and premium JHP defensive loads. No ammo restrictions beyond normal 9mm SAAMI specifications.
Key Features
- Duty Series 4150 CMV steel — stress-relieved, air-gauge tested, headspace checked
- Salt bath nitride finish inside and out — hard, corrosion-resistant, no-peel
- Threaded muzzle 1/2×28 TPI — suppressor and compensator compatible
- Drop-in fit for factory SIG® P365 slides — no gunsmithing required
- Tighter-than-OEM tolerances — improved lockup and consistency
- Conventional 1:10 button rifling — cast lead and jacketed ammunition compatible
- 11° target crown — consistent, repeatable bullet release
- Not a firearm — no FFL, ships direct
- Faxon Lifetime Guarantee
- Made in Ohio, USA
Specifications
- BrandFaxon Firearms
- MPN365A910NFNOQ-T
- UPC810209950088
- PlatformSIG® P365
- Caliber9mm Luger
- SeriesDuty Series
- Length3.71”
- ProfileDrop-In, Threaded
- MaterialStress-Relieved 4150 CMV Steel
- RiflingConventional, Button-Rifled
- Twist Rate1:10 Right-Hand
- FinishSalt Bath Nitride (In & Out)
- Muzzle Threads1/2×28 TPI
- Crown11° Target Crown
- FitDrop-In, Factory P365 Slides
- O-Ring NoteMay need removal to install
- Firearm StatusNot a Firearm — No FFL
- OriginMade in Ohio, USA
- WarrantyFaxon Lifetime Guarantee
- MSRP$97.00
Frequently Asked Questions
Is this barrel a drop-in fit?
Yes. The Duty Series P365 barrel is designed for direct replacement in factory-spec SIG® P365 slides with no gunsmithing required. Note: due to the slim profile of the P365 slide, you may need to remove the O-ring from the barrel before seating it in the slide. This is a known characteristic of the P365 platform and does not affect function.
Can I use this barrel with a suppressor?
Yes. The 1/2×28 TPI threaded muzzle accepts most 9mm direct-thread suppressors and compensators without an adapter. When running suppressed, you will likely need taller sights (often called suppressor-height or night-sight height sights) to achieve a usable sight picture over the suppressor body, as factory P365 sights will be blocked. A thread protector is recommended when carrying without a muzzle device to protect the threads.
What ammunition can I use?
All standard 9mm Luger SAAMI-spec ammunition, including FMJ, JHP, and cast lead. The Duty Series barrel uses conventional button rifling with land-and-groove geometry, which is safe for cast lead bullets — unlike polygonal-rifled barrels where cast lead use is generally not recommended. The 1:10 twist rate stabilizes all common 9mm bullet weights.
What is the difference between the Duty Series and Match Series?
The Duty Series uses 4150 CMV steel with a salt bath nitride finish inside and out. It is optimized for hard-use reliability, wear resistance, and corrosion protection across the widest range of conditions — the right choice for carry, duty, and training use. The Match Series uses 416-R stainless steel and is oriented toward accuracy-optimized target and competition applications where the slight additional corrosion sensitivity of stainless is an acceptable tradeoff. For everyday carry on a P365, the Duty Series is the appropriate choice.
Does this require an FFL transfer?
No. A pistol barrel is a component, not a serialized firearm. This barrel ships directly to your door with no FFL transfer required. Verify your local laws before ordering.
Is this covered by the Faxon Lifetime Guarantee?
Yes. Contact Faxon through faxonfirearms.com for any warranty service needs.
About Faxon Firearms
Faxon Firearms is a precision firearms manufacturer headquartered in Greater Cincinnati, Ohio. Built on a machining heritage dating to 1978, Faxon designs and machines pistol barrels, rifle barrels, complete pistols, complete rifles, upper receivers, and accessories for the AR-15, AR-10, FX-19, and Glock® platforms — sold direct at faxonfirearms.com and through a national dealer network. Every Faxon product is covered by our Lifetime Guarantee. Welcome to The Fellowship of Firearms®.
“SIG®” and “P365” are trademarks of SIG Sauer, Inc. Faxon Firearms is not affiliated with, endorsed by, or sponsored by SIG Sauer, Inc. All trademarks are the property of their respective owners.
Warranty
Faxon Lifetime Guarantee. Covers manufacturing and material defects to the original purchaser. Excludes damage from misuse, neglect, non-standard ammunition, or modifications. Register your product at faxonfirearms.com/product-registration to expedite service. For purchases through dealers or distributors, warranty repairs are handled directly by Faxon Firearms; refunds must be processed through the selling entity. Full policy: faxonfirearms.com/warranty-privacy-terms/Customers Also Shopped These Items
Reviews
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P365 barrel
Shoots great. The comp that I purchased really help with control for follow up shots. The barrel and comp preform perfectly