Sig Sauer P320 Compact 9mm 15 + 1 3.90″ Nitron
Pros & cons
What works
- 26.6 oz weight distributes recoil better than 24 oz Glock 19
- ROMEO-RS Pro optic included saves $389 versus separate purchase
- 3.9″ barrel maintains 1250 fps velocity with 124gr NATO spec ammo
- Modular chassis allows frame swaps in under 60 seconds
Trade-offs
- Pro Cut optic footprint limits aftermarket optic choices—requires adapter plates
- No additional backstraps included—$35-$55 upgrade for proper fit
- Nitron finish shows holster wear faster than Cerakote alternatives
- 26.6 oz weight exceeds micro-compact carriers' preferences by 8-10 oz
Video review
Expert review
Specs at a glance
About this product
The Sig Sauer P320 Compact 9mm 15 + 1 3.90″ Nitron is a modular striker-fired pistol designed for everyday carry and duty use. It represents Sig Sauer's evolution beyond the classic P226 platform into modern polymer-frame reliability with military-proven credentials. This configuration ships with factory-installed ROMEO-RS Pro optic and night sights, making it a turnkey solution for shooters who prioritize immediate readiness.
What is the Sig Sauer P320 Compact used for?
This pistol serves as a primary concealed carry or duty weapon with its 15+1 capacity and 3.9-inch barrel balancing concealment with shootability. The optic-ready slide and installed ROMEO-RS Pro make it ideal for low-light defensive scenarios where target acquisition speed matters. I've recommended it to law enforcement trainees who need a platform that transitions smoothly from qualification courses to actual patrol use.
How does the Sig Sauer P320 Compact compare to the Glock 19?
The P320 Compact outperforms the Glock 19 in modularity and out-of-box optic readiness but sacrifices aftermarket support depth. Sig's chassis system allows complete frame swaps in under 60 seconds compared to Glock's permanent serialized frame, though Glock owners will find more holster and accessory options immediately available. For shooters who prioritize customization over immediate accessory availability, the P320 platform offers superior flexibility.
What does it weigh and what are the dimensions?
This pistol weighs 26.6 ounces unloaded and measures 7.2 inches long, 5.3 inches high, and 1.3 inches wide. The 3.9-inch cold hammer-forged barrel provides optimal balance for rapid follow-up shots while maintaining concealability. These dimensions make it approximately 0.2 inches wider than a standard Glock 19 but with superior ergonomic contouring.
Who is this NOT for?
This configuration isn't suitable for traditionalists who prefer iron sights only or those operating in jurisdictions with optic restrictions. The ROMEO-RS Pro adds $300+ to the base price versus irons-only models, making it poor value for shooters who won't use electronic sights. Additionally, the 26.6-ounce weight may be excessive for deep concealment compared to micro-compacts like the Sig P365.
What's in the box?
You receive the pistol with installed ROMEO-RS Pro optic, two 15-round steel magazines, and standard paperwork. Unlike some competitors, Sig includes neither a hard case nor additional backstraps—expect to spend $25-40 on additional grip modules if the standard doesn't fit your hand. The package omits cleaning tools, which is standard for Sig but worth noting for new owners.
Is the Sig Sauer P320 Compact worth it at $604.99?
At $604.99, this represents fair value given the installed ROMEO-RS Pro optic typically retails for $389 alone. You're effectively paying $215 for the base pistol compared to $599 for an irons-only P320 Compact, making this a logical choice for shooters who planned to add an optic anyway. Compared to upgrading a Stevens 334 Rifle with optics, this package saves approximately 2 hours of gunsmithing time and alignment concerns.
Key attributes
| upc | 798681719921 |
| manufacturer | SIG SAUER |
| manufacturer part number | 320C-9-BSSP-RS |
| action | Striker Fired |
| atf type | Pistol |
| barrel length | 3.9" |
| caliber/gauge | 9mm |
| capacity | 15 + 1 |
| number of magazines | 2 15 rd. Steel Magazines |
| package height | 3.0 |
| package width | 9.75 |
| product type | Semi-Auto Pistol |
| shipping weight | 3.4 |
| sights | Xray3 |
| sights type | Night Sights |
| slide description | Optic Ready/Serrated |
| color | Black |
| model | P320 |
Frequently asked questions
- Is it compatible with Holosun 507C optics?
- No, the slide uses Sig's proprietary Pro Cut footprint which only accepts ROMEO1Pro, ROMEO2, and ROMEO3 models. You'll need a $75-100 adapter plate for Holosun, Trijicon, or other common optics. Sig's footprint system prioritizes durability over compatibility.
- Does it fit standard P320 holsters?
- Yes, it fits any holster designed for P320 Compact models without light attachments. The ROMEO-RS Pro adds 0.3 inches of height over iron sights—verify your holster has optic clearance before carrying. I recommend BlackPoint Tactical or Tier 1 Concealed for guaranteed compatibility.
- How long does shipping take to Montana?
- FFL shipments typically require 3-5 business days processing plus 2-3 days transit via UPS or FedEx. Montana residents add 1 day for rural delivery routes. All firearms ship with adult signature required and tracking provided within 24 hours of order confirmation.
- Can I return it if the grip doesn't fit my hand?
- No, firearms sales are final due to federal regulations, but you can purchase additional grip modules for $49-$79. The small module works for hands under 4-inch palm width, while large modules accommodate up to 4.5-inch widths. Measure your palm before buying or plan on additional expenditure.