Sig Sauer MCX Rattler LT – SBR, 300 BLK, 6.75", Black, Folding Stock (WRMCX-300B-6B-LT-SBR)
The MCX Rattler LT SBR is SIG’s factory short-barreled rifle in 300 AAC Blackout: a 6.75-inch cold-hammer-forged barrel, short-stroke gas-piston system, fully ambidextrous controls, SIG QD suppressor-ready flash hider, SIG Flat Blade Match trigger, and a Folding Minimalist Plus stock. Finish is black anodized; one 30-round polymer magazine is included. Overall length is 24.9 inches (about 17.1 inches folded). Weight is approximately 92.8 ounces (5.8 lb). SIG part number WRMCX-300B-6B-LT-SBR, UPC 798681648047.
This listing is for the SBR only. NFA rules apply to transfer of a short-barreled rifle.
Factory SBR, Folding Minimalist Plus
This SKU is a factory SBR with the Folding Minimalist Plus stock. Folded length is about 17.1 inches for compact storage and transport when legally configured.
6.75" CHF 300 BLK Barrel
- 6.75" cold-hammer-forged barrel, 1:5 twist
- 5/8×24 tapered-shoulder threads with SIG QD suppressor-ready flash hider
- Adjustable gas for suppressed / unsuppressed use
- M-LOK / Picatinny handguard; AR-compatible PDW grip layout
Sig Sauer MCX Rattler LT SBR Specifications
| Manufacturer | Sig Sauer |
| Model | MCX Rattler LT SBR |
| Part Number | WRMCX-300B-6B-LT-SBR |
| UPC | 798681648047 |
| Firearm Type | Short-Barreled Rifle (SBR) — NFA |
| Cartridge | 300 AAC Blackout |
| Action | Semi-Automatic, short-stroke piston |
| Barrel Length | 6.75" cold hammer forged |
| Twist Rate | 1:5 |
| Muzzle Threads | 5/8×24, tapered shoulder |
| Muzzle Device | SIG QD suppressor-ready flash hider |
| Stock | Folding Minimalist Plus |
| Capacity | 30 rounds |
| Magazines Included | (1) 30-round polymer |
| Receiver Finish | Black anodized |
| Trigger | SIG Flat Blade Match |
| Overall Length | 24.9" |
| Folded Length | 17.1" |
| Overall Width | 2.25" |
| Height | 7.4" |
| Weight | approximately 92.8 ounces (5.8 lb) |
What’s in the Box
- Sig Sauer MCX Rattler LT SBR
- (1) 30-round polymer magazine
Frequently Asked Questions
Is this an SBR?
Yes. This listing is the factory SBR only. NFA transfer rules apply.
What stock does it have?
A Folding Minimalist Plus stock (about 17.1" folded).
What caliber and barrel length?
300 AAC Blackout with a 6.75-inch cold-hammer-forged barrel.
Does it include a magazine?
Yes — one 30-round polymer magazine.
Internal Reference:
WRMCX-300B-6B-LT-SBR
Barcode:
798681648047
| Brand: Sig Sauer |
| Model: MCX |
| Caliber: .300 Blackout |
| Capacity: 30 |
| Firearm Action: Semi-auto |
| Barrel Length: 7" |
Check Shipping Availability
This product may have shipping restrictions in some states.
Customer Reviews
Write a Review
This item cannot be shipped to the following locations due to legal or carrier restrictions:
Restriction Details
This product cannot be sold or shipped to your location due to magazine capacity restrictions. Magazine capacity cannot exceed 10rd. If you believe this to be incorrect or if you're exempt from the restriction, please contact us at 636-791-1655.
Affected States/Territories (10):
Restriction Details
Colorado prohibits magazines with a capacity exceeding 15rd. If you believe this is in error or if you are exempt from the restriction, please contact us at 636-791-1655.
Affected States/Territories (1):
Restriction Details
Vermont restricts rifle magazine capacity to 10rd. This exceeds the state's restricted capacity. If you believe this is in error or if you are exempt from the restriction, please contact us at 636-791-1655.