The Mossberg 940 JM Pro is a favorite among competitive shooters and hunters. Upgrading the magazine tube is probably the most important thing so you don't waste time reloading, the last maybe two shots that make or break your time.
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Problems From The Past
Some may experience problems with smooth feeding, and let's not gloss over the handling quirks these extensions can cause. You might even hit a snag during install or end up needing tweaks you didn't see coming.
- Bending or failure of mag tubes after a couple rough toss into stage buckets.
- Coatings flaking off, leading to rust.
Top Mossberg 940 JM Pro Extended Mag Tubes
GG&G Magazine Tube Extension
- Key Features:
- Boosts capacity by two rounds.
- Comes with a barrel clamp and a magazine tube nut.
- Made of 6061-T6 aluminum; Mil-Spec hard anodized finish.
- Weighs 7.2 oz and measures 6 7/8 inches in length.
- Easy to install with no major modifications.
- Check it out here.
Nordic Components MXT Magazine Extension Kit
- Key Features:
- Customizable with lengths up to +9.
- Crafted from 6000-series aluminum with a matte finish.
- Designed to fit the extension perfectly with your barrel.
- Known for its performance and easy installation.
- Learn more here.
Briley 12+1 Magazine Extension
- Key Features:
- Expands capacity to 12+1 rounds.
- Lightweight yet durable.
- Includes a spring, end cap, and mounting components.
- Straightforward to install but watch that spring tension.
- Refresher here.
Mossberg Factory Magazine Tube Extension
- Key Features:
- Boosts capacity to nine rounds.
- OEM part for unmatched compatibility.
- Seamless fit with the Mossberg 940 JM Pro design.
- More details here.
Legal Limits
There are legal cap limits to consider, particularly with hunting or competitive shooting events. Watch your back on these details to avoid getting dinged at game time.