FirearmsMossbergSold by Fin Feather Fur Outfitters

Mossberg

Mossberg 940 JM Pro Optic-Ready 12 Gauge 3" Chamber 24" Barrel

Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.

12 Gauge

A 3" chamber

24" Vent

Rib barrel for a smooth,

Optic-ready Configuration

For sight mounting flexibility

Includes Briley

Extended choke set

Adjustable Length

Of pull from 13" to

$1049.99
View on Fin Feather Fur Outfitters

You'll be taken to Fin Feather Fur Outfitters to complete your purchase.

Hunter's Outpost earns a commission from affiliate links at no extra cost to you.

SKU: 85165-015813851657

Overview

Built for shooters who want a competition-oriented semi-auto, this 12 gauge is set up for fast handling and adaptable fit. The 3" chamber and 24" vent rib barrel support a smooth, controlled shooting setup, while the optic-ready design gives you room to configure it for your preferred sighting system. An adjustable length of pull and synthetic stock add fit flexibility, and the included Briley extended choke set provides added versatility for different shooting needs. With a 9+1 capacity and matte blue finish, it presents a practical, purpose-driven package for high-volume range use.

Why Hunters Choose the Mossberg

Optic-ready Design

Supports sight customization for competition

Semi-auto Action

Is suited to high-performance shooting

3" Chamber

Accommodates a range of 12

24" Vent

Rib barrel supports a smooth,

Includes Briley

Extended choke set for added

Key Features

  • 12 gauge semi-auto shotgun with a 3" chamber
  • 24" vent rib barrel for a smooth, consistent shot
  • Optic-ready configuration for sight mounting flexibility
  • Includes Briley extended choke set
  • Adjustable length of pull from 13" to 14.25"
  • 9+1 capacity with front fiber optic sight

Best Used For

  • Competition shooters wanting a semi-auto 12 gauge with an optic-ready setup and adjustable fit.
  • Hunters who prefer a 24-inch barrel and vent rib configuration for controlled, consistent handling.
  • Users needing a 3-inch chamber and 9+1 capacity for higher-volume shooting applications.
  • Shooters who want a customizable length of pull for better fit across different clothing layers.
  • Those looking for a synthetic-stock shotgun with front fiber optic sight and matte blue finish.

Specifications

Action TypeSemi-Auto
Barrel FinishMatte Blue
Barrel Length24"
Capacity9+1
Chamber Size3"
ChokeBriley Ext Set
Gauge12 Gauge
Length44.75"
Lop13"-14.25"
Lop TypeAdjustable
SightsFront FO; Optic-Ready
StockAdj. LOP, Cast, Drop - Synthetic (Black)
Weight7.75 oz

Pros

  • Optic-ready design supports sight customization for competition setups.
  • Semi-auto action is suited to high-performance shooting applications.
  • 3" chamber accommodates a range of 12 gauge loads.
  • 24" vent rib barrel supports a smooth, consistent sight picture.
  • Includes Briley extended choke set for added configuration options.
  • Adjustable length of pull offers a more customizable fit.

Considerations & Trade-offs

  • The 3" chamber and semi-auto setup are oriented toward high-performance shooting, so this model is more specialized than a general-purpose field shotgun.
  • The 24" barrel and 44.75" overall length may feel less compact in tight blinds, vehicles, or dense cover.
  • Capacity is listed at 9+1, which is useful for competition-style use but may be more than some hunters want for simpler carry or handling.
  • The adjustable stock and optic-ready setup add flexibility, but they also make this a more feature-specific platform than a basic fixed-config shotgun.

Suggested Comparisons

  • Semi-auto competition shotguns
  • 12 gauge shotguns
  • Optic-ready shotguns
  • Shotguns with adjustable length of pull

Suggested Accessories

  • Optic mounting hardware
  • 12 gauge ammunition
  • Shotgun cleaning kit
  • Choke tube case

Frequently Asked Questions

What gauge and chamber size does the Mossberg 940 JM Pro use?

It is a 12 gauge shotgun with a 3" chamber.

Is this shotgun optic-ready?

Yes. The product is listed as optic-ready.

What barrel length does it have?

It has a 24" vent rib barrel.

What choke setup is included?

It comes with a Briley extended choke set.

What fit adjustments are available?

The shotgun has an adjustable length of pull, listed at 13" to 14.25", with an adjustable synthetic stock.