SIG Sauer <product>P320 AXG Legion 9mm (IMC)</product> vs <product>P365-380 Optic Ready w/ Ambi Manual Safety (MA Compliant)</product>: Detailed Comparison

Key Differences at a Glance

• Size/role: P320 AXG Legion is a full-size, duty/competition-leaning pistol; P365-380 OR w/ Ambi MS (MA Compliant) is a micro-compact optimized for concealment. (sigsauer.com)
• Caliber: P320 AXG Legion is 9mm Luger; P365-380 OR w/ Ambi MS (MA Compliant) is .380 Auto. (sigsauer.com)
• Recoil mitigation: P320 AXG Legion uses a slide-integrated expansion chamber (IMC concept) for recoil reduction; P365-380 relies primarily on the inherently softer .380 Auto plus its lighter slide/updated guide rod design. (sigsauer.com)
• Capacity: P320 AXG Legion ships with (3) 21-round (or (3) 10-round) magazines; P365-380 ships with (2) 10-round magazines. (sigsauer.com)
• Weight (with magazine): P320 AXG Legion 36.1 oz vs P365-380 15.7 oz—a major handling and carry difference. (sigsauer.com)
• Manual safety: The P320 AXG Legion is not available with a manual safety; the requested P365-380 OR w/ Ambi MS (MA Compliant) is a manual-safety variant (and the P365-380 line is offered with/without). (sigsauer.com)
• State compliance: The P365-380 model table explicitly lists a Massachusetts compliant variant; the P320 AXG Legion page does not list MA compliance in the same way. (sigsauer.com)

Current Market Position & Pricing

Price reality (as of February 1, 2026)

• Manufacturer guidance: SIG’s consumer-facing product pages typically present model tables/specs but do not consistently publish an MSRP line-item on the page.
• Retail pricing requirement note: You requested “current retail pricing across multiple retailers,” but you also required no competitor retail/e-commerce citations or links. Because pricing is volatile and retailer listings are disallowed as sources here, I’m limiting pricing discussion to manufacturer-controlled pricing signals and positioning rather than quoting live retail price tags.

Market positioning

• P320 AXG Legion sits in SIG’s LEGION lineup with an all-metal AXG (alloy) grip module, magwell, premium sights, and an optic-ready slide—positioned as a higher-feature, performance-oriented full-size. (sigsauer.com)
• P365-380 OR w/ Ambi MS (MA Compliant) fits SIG’s P365 micro-compact carry ecosystem: lighter weight, smaller footprint, optic-ready, and designed around easier handling and reduced recoil/racking effort for many shooters. (sigsauer.com)

Availability signals (manufacturer-side)

• Both product pages include SKU/model tables indicating current production offerings; the P320 AXG Legion page lists multiple SKUs (standard, 10-round, and RXX optic bundle variants). (sigsauer.com)
• The P365-380 page shows an optic-ready configuration and indicates a Massachusetts state-compliant entry in its model table. (sigsauer.com)

Specifications Comparison

Performance and Accuracy

• Practical accuracy potential: The P320 AXG Legion has a longer sight radius (5.9") and significantly more mass (36.1 oz w/ mag), both of which generally support easier steadiness and faster follow-up shots—especially for newer shooters who struggle with micro-compact stability. (sigsauer.com)
• Recoil impulse management: SIG explicitly describes the P320 AXG Legion as using a two-port slide integrated expansion chamber aimed at recoil mitigation (SIG marketing claims “up to 25% recoil reduction”). Treat the percentage as a manufacturer claim that may vary with load, grip, and shooter technique. (sigsauer.com)
• .380 Auto handling advantage: SIG positions the P365-380 around “less recoil” and “reduced racking force,” which aligns with the cartridge and platform goal: easier manipulation and softer impulse in a micro-compact envelope. (sigsauer.com)
• Reliability/durability considerations: Both are modern striker-fired SIG pistols, but the P365-380 page highlights design details like a redesigned captured guide rod and a lightened slide/barrel set. The P320 AXG Legion combines a stainless slide with an alloy AXG module and a full-size duty geometry. (sigsauer.com)

Ergonomics and Handling

• Grip size & control: The P320 AXG Legion uses the AXG metal grip module with Hogue G10 grip panels and a magwell—features that typically improve purchase, reload indexing, and recoil control, especially with larger hands or when shooting strings at speed. (sigsauer.com)
• Carry comfort: The P365-380 OR w/ Ambi MS (MA Compliant) is dramatically lighter and smaller in every major dimension listed, which is the real-world driver for day-to-day concealment compliance (comfort = more consistent carry). (sigsauer.com)
• Controls:
  • P320 AXG Legion: no manual safety option per SIG’s product page, simplifying the manual of arms but removing that administrative control for those who prefer it. (sigsauer.com)
  • P365-380 line: offered with/without manual safety; the MA-compliant manual-safety version is commonly selected by buyers in restrictive states or those wanting an external safety lever. (sigsauer.com)

Features and Accessories

• Optics compatibility:
  • P320 AXG Legion: optic-ready and stated compatible with ROMEO1Pro/ROMEO2 and other common footprints (SIG notes compatibility on the product page). (sigsauer.com)
  • P365-380: optic cut is described as compatible with ROMEO-X Compact footprint. (sigsauer.com)
• Lights/lasers: Both list an accessory rail (P320: M1913; P365-380: SIG rail). In practice, the P320’s full-length rail standardization tends to broaden light fitment, while the SIG micro rail often requires model-specific lights. (sigsauer.com)
• Modularity:
  • P320 AXG Legion is part of the P320 FCU ecosystem (implied by P320 platform design and SIG’s modular lineup), but your specific model is built around the AXG frame and the Legion slide system.
  • P365-380 shares the FCU and grip module architecture with P365 9mm, and SIG notes holster compatibility with standard P365 holsters. (sigsauer.com)

Real-World Applications

• Concealed carry (daily, under light clothing): P365-380 OR w/ Ambi MS (MA Compliant) is the more practical tool due to size/weight, and SIG’s design intent emphasizing easier handling and reduced racking force. (sigsauer.com)
• Home defense (with a weapon light) & range training: P320 AXG Legion offers higher onboard capacity and a larger, heavier platform that’s easier to shoot well quickly for many people. Its M1913 rail and full-size geometry also make light mounting straightforward. (sigsauer.com)
• Competition/range volume: The P320 AXG Legion’s weight, magwell, and recoil-mitigation concept align with faster shot-to-shot recovery and more forgiving handling at speed. (sigsauer.com)
• New shooters / recoil-sensitive shooters: If the goal is minimal recoil and easier slide manipulation in a small gun, the P365-380 was purpose-positioned that way by SIG. If the shooter can conceal a larger pistol, many will still find the heavier P320 AXG Legion subjectively easier to shoot accurately due to mass and grip area. (sigsauer.com)

Expert and User Reviews Analysis

• What I can substantiate from official sources: SIG’s official descriptions emphasize:
  • P320 AXG Legion: slide-integrated expansion chamber, AXG metal grip module, magwell, Hogue G10 grips, optic-ready configuration. (sigsauer.com)
  • P365-380: less recoil, reduced racking force, optic-ready slide, compatibility with P365 holsters, and general EDC intent. (sigsauer.com)
• Limitations: Your sourcing rules prevent citing the most common third-party places where large volumes of user feedback live (retailer reviews, marketplaces, deal aggregators). If you want a dedicated “reviews round-up,” I can do it using industry publications only (print/digital gun media), but you’ll need to confirm you consider those “authoritative technical sources” under your policy.

Final Verdict

• Choose the P365-380 OR w/ Ambi MS (MA Compliant) if your priority is concealability, low carry burden, softer recoil than typical micro-compact 9mm, and having an external manual safety (especially where MA compliance matters). (sigsauer.com)
• Choose the P320 AXG Legion 9mm (IMC) if your priority is shootability at speed, higher magazine capacity, a full-size rail, and a heavier metal-grip platform that supports controllability and confidence during longer range sessions. (sigsauer.com)

Sources

SIG SAUER. "P320 AXG Legion | Enhanced Performance 9mm Luger Pistol." SIG SAUER. (Accessed 2026-02-01). https://www.sigsauer.com/p320-axg-legion.html SIG SAUER. "SIG SAUER P365 380 | America's #1 Micro Compact Pistol." SIG SAUER. (Accessed 2026-02-01). https://www.sigsauer.com/p365-380.html SIG SAUER. "SIG SAUER Expands LEGION Series with P320 AXG LEGION." SIG SAUER Blog. (Accessed 2026-02-01). https://www.sigsauer.com/blog/sig-sauer-expands-legion-series-with-p320-axg-legion SIG SAUER. "Experience Brilliance with P365 380 Rainbow." SIG SAUER. (Accessed 2026-02-01). https://www.sigsauer.com/p365-380-rainbow.html