X-BOW FMA Supersonic REV XL M4 | 120 lbs / up to 420+ FPS Compact Compound Crossbow

The X-BOW FMA Supersonic REV XL M4 combines the high-performance REV compound platform with an adjustable M4-style shoulder stock. Its reverse compound design and longer power stroke enable speeds of up to 420+ FPS, while the M4 stock provides additional shoulder support, adjustability and stability compared with the stockless REV Basic.

The REV XL M4 is therefore aimed at shooters who want to combine the exceptional performance and narrow profile of the Supersonic REV with a more conventional shoulder-supported shooting position. Its integrated cable and lever cocking system also makes the 120 lbs compound platform practical to cock without attaching a separate rope cocking device for every shot.

Reverse compound technology: up to 420+ FPS

The Supersonic REV uses different compound geometry from the standard Supersonic. Its reverse design creates a longer power stroke of approximately 8.25 inches / 21 cm, allowing the bolt to be accelerated over a greater distance.

Actual velocity depends on the weight and type of REV bolt:

• High Range REV 100 grain: up to approx. 420+ FPS
• Standard REV 120 grain: approx. 390–400 FPS
• High Impact REV 140 grain: approx. 350–360 FPS
• Minimum bolt weight: 100 grain

Maximum FPS therefore tells only part of the story. A lighter High Range REV bolt maximises velocity, while a heavier REV bolt trades some speed for additional mass. Always select the correct REV bolt for the intended application and observe the minimum bolt weight.

Adjustable M4-style shoulder stock

The key difference from the REV Basic is the adjustable M4-style shoulder stock. It creates a defined shoulder support point and allows the shoulder fit to be adjusted to suit the shooter and preferred shooting position.

The M4 configuration is therefore particularly attractive when you want to retain the REV's narrow dimensions and high performance while adding greater control, support and stability when aiming.

Integrated cable and lever cocking system

The REV features an integrated cable and lever cocking system. Operating the rear handle mechanically draws the string into its cocked position.

This eliminates the need to attach a separate rope cocker for every shot. The system substantially reduces the force the shooter actually needs to apply compared with the nominal 120 lbs draw weight and is one of the Supersonic platform's key practical advantages.

Exceptionally narrow high-performance compound front end

Despite its high performance, the REV compound front end remains exceptionally narrow. Cocked axle-to-axle width is approximately 4.9 inches / 12.4 cm, increasing to around 8.5 inches / 21.7 cm uncocked. The M4 shoulder stock increases overall length but does not change the exceptionally narrow character of the compound front end.

Higher performance also means greater technical load

The REV's high velocity is achieved by transferring more energy to the bolt over a longer power stroke. This delivers impressive performance, but also means that the string, cables, cams, bolts and other components are subjected to greater loads than on the standard Supersonic.

Regular inspection of the string and cables is therefore particularly important. Check them before use for wear, damage and fraying and follow the manufacturer's maintenance instructions. The REV is primarily the right choice when you genuinely want the additional performance and are prepared to give the platform the corresponding level of maintenance.

REV versus the standard Supersonic

Although both belong to the same Supersonic family, their technical and practical positioning is different:

• Supersonic 120 lbs: the more accessible compact compound platform, with speeds up to approximately 330 FPS, lower technical loads and less demanding target and maintenance requirements.
• Supersonic REV 120 lbs: the high-performance reverse compound platform with a longer power stroke and speeds up to 420+ FPS, but also greater loads on the string, cables, bolts and other components.

The REV is therefore not simply the “faster and better” Supersonic. Its additional performance comes with greater demands on suitable REV bolts, a more capable target, careful maintenance and regular inspection of the string and cables. If maximum velocity is not required, the standard Supersonic may actually be the more practical and economical choice.

Your target matters

A crossbow capable of speeds up to 420+ FPS places considerably greater demands on a target than a lighter recreational crossbow. Always use a crossbow target explicitly suitable for the speed and energy of high-performance compound crossbows. An inadequate target can allow bolts to penetrate too deeply or even pass completely through.

REV Basic or REV XL M4?

Both configurations use the same high-performance REV principle. The key difference is shoulder support:

• REV Basic: no shoulder stock; the shortest and most minimalist REV configuration.
• REV XL M4: adjustable M4-style shoulder stock for additional shoulder support, adjustability and a more stable shooting position.

Choose the REV Basic when minimum dimensions are the highest priority. Choose the REV XL M4 when you are willing to accept additional length in return for greater shoulder support, control and stability.

Key specifications

• Brand: X-BOW FMA
• Model: Supersonic REV XL M4
• Type: compact reverse compound crossbow
• Draw weight: 120 lbs
• Maximum bolt speed: up to 420+ FPS depending on bolt
• High Range REV 100 grain: up to approx. 420+ FPS
• Standard REV 120 grain: approx. 390–400 FPS
• High Impact REV 140 grain: approx. 350–360 FPS
• Minimum bolt weight: 100 grain
• Power stroke: approx. 8.25 inches / 21 cm
• Cocked width: approx. 4.9 inches / 12.4 cm axle-to-axle
• Cocked total width: approx. 7.5 inches / 19 cm
• Uncocked width: approx. 8.5 inches / 21.7 cm axle-to-axle
• Uncocked total width: approx. 11.4 inches / 29 cm
• Cocking system: integrated cable / lever system
• Stock: adjustable M4-style shoulder stock
• Mounting rail: 19 mm
• Colour: black

What's included?

The X-BOW FMA Supersonic REV XL M4 is supplied with:

• X-BOW FMA Supersonic REV XL M4 120 lbs crossbow
• adjustable M4-style shoulder stock
• 3 suitable REV bolts
• assembly hardware
• manual