FX Impact M4 .30 Cal PCP Bullpup Air Rifle, STX Superior 29.5 Inch Shrouded Barrel, Power Plenum 750, Copper/Bronze Finish
This FX Impact M4 stands out as a .30 caliber PCP bullpup built on a CNC-machined aluminum chassis with a distinctive copper/bronze anodized finish. It features the FX Power Block and Power Plenum 750, a 29.5 inch STX Superior shrouded barrel, a carbon-fiber air bottle, and a 16-round rotary magazine. Overall condition is excellent, with only faint signs of prior handling.
Condition
Overall Condition: Excellent condition, showing only faint signs of any prior use or handling.
Bore Overall Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: There are minimal markings from prior handling and use. The bore is bright and clean. Please refer to the photos for a full view of cosmetic details.
What's Included
- 1x 16-round FX Impact rotary drum magazine
- Hard case with custom foam cut
- Faux suppressor
The Impact M4 platform is a pre-charged pneumatic, side-lever bullpup repeater built in Sweden. Its aluminum chassis is copper/bronze anodized and paired with a skeletonized stock, rubber butt pad, and a rubberized finger-grooved pistol grip. Length of pull is 14 inches, and a manual safety is fitted.
Air delivery is anchored by the FX Power Block and the Power Plenum 750 (75 cc), fed by a carbon-fiber air bottle. A WIKA gauge monitors system pressure with a maximum fill of 250 bar, providing precise, at-a-glance pressure information.
The 29.5 inch FX Smooth Twist X (STX) Superior barrel is shrouded. The sale includes a faux suppressor. The design supports quiet, consistent performance while keeping overall handling compact for a long-barreled bullpup.
Controls and setup are straightforward: a smooth side-lever charging handle, the externally adjustable FX Quick Set Trigger, and integrated accessory rails with a scope mount for easy setup. The rifle uses a 16-round rotary magazine for .30 caliber pellets.

