Brand: US Palm
Model: Storm CAT4
Platform: AR-15
Caliber: 5.56 NATO
Gas System: Mid-Length / Direct Impingement
Barrel Length: 16"
Barrel Description: Cold Hammer Forged
Barrel Finish: Black
Capacity: 30rds
Twist Rate: 1:7
Muzzle Thread: 1/2 x 28
Muzzle Device: US PALM Hurricane Hybrid Muzzle Device
Stock Description: Magpul DT Carbine Stock
Stock Material: Polymer
Grip Description: US Palm Grip
Grip Material: Polymer
Furniture Finish: Black
Upper Receiver Material: 7075-T6 Aluminum
Upper Receiver Finish: Storm Green
Lower Receiver Material: 7075-T6 Aluminum
Lower Receiver Finish: Storm Green
FCG: Hiperfire EDT Designated Marksman Trigger
Rail Description: 7-Sided Mono-Loc Handguard System
Rail Material: Aluminum
Rail Finish: Storm Green
Attachment Style: M-LOK
Safety: 2-Position / Ambidextrous
Bolt Carrier Group: Yes
Charging Handle: Ambidextrous
OAL: 33.5" - 36.8"
Weight: 7 lbs

Features

The US PALM Storm CAT4 is a refined evolution of the M4 platform, engineered to meet the demands of modern shooters seeking durability, control, and enhanced performance. Designed with input from industry professionals, this rifle incorporates a range of upgrades to maximize service life and operational capability. A standout feature is the Hurricane Hybrid muzzle device, which combines flash suppression and recoil mitigation through a helical, twisted-prong design that follows the barrel’s twist direction, helping reduce muzzle rise while effectively dispersing flash.

Fully ambidextrous controls provide intuitive access to the safety selector, magazine release, bolt catch, and charging handle without requiring a change in grip, supporting faster manipulation and adaptability in dynamic shooting environments. The Mono-Loc handguard system delivers exceptional rigidity through a precision rear-locking interface that integrates securely with the upper receiver, maintaining alignment for optics and accessories under demanding use. With a continuous top rail, full M-LOK compatibility, and a rigid profile, the platform offers a stable and repeatable shooting experience designed for control, consistency, and high-performance handling.

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It is the customer’s responsibility for understanding state laws regarding all purchases made. For a comprehensive list of all Shipping Restrictions, please refer to our Shipping Restrictions By State Page found Here.

All NFA Rules Apply

These items are controlled by the U.S. Government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. They may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.

Magazines will be removed from firearms when shipping to states with magazine capacity restrictions.

California 10+ Round Magazine Buyers: PSA values your freedom and constitutional rights above all else. However, PSA will not accept new orders nor will ship any order until the Ninth Circuit Federal Court of Appeals mandate becomes finalized. Once this mandate is finalized, we will start accepting new orders and ship 10+ round magazines to California Customers.

WARNING: Handling firearms or firearms parts can expose you to lead and other petroleum products known to the State of California to cause cancer, birth defects, or other reproductive harm. Wash hands thoroughly after handling. For more information go to www.p65warnings.ca.gov (CA Health and Safety Code Section 25249.6).