VFC HK416 M4 AR15 GBB Reenforced Outer Barrel Extension Chamber VG20ADC040

Reinforced Upgrade for VFC VG20ADC040 (HK416A5 / AR-15 GBB)

Precision CNC-machined replacement for the fragile OEM plastic part. Designed to lock the barrel solidly, improve chamber alignment, and survive repeated disassembly.

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Key Features

• Fixes Barrel Wobble – Reinforced body and integrated barrel nut greatly reduce or eliminate barrel play on VFC HK416A5 GBB platforms.

• Drop-In Compatibility – Slightly enlarged chamber bore (CB) accepts OEM and most aftermarket hop-up units—e.g., GHK chamber—without fitting or modification. No promise to accept all aftermarket parts.

• Self-Centering Design – Internal CB taper auto-centers the inner barrel; the integrated barrel nut maintains alignment under load.

• CNC Precision – Tight, repeatable tolerances for consistent assembly and accuracy.

Compatibility

• Fits all VFC AR-15 / M4 / HK416 GBB models (including HK416A5).

• Direct upgrade/replacement for VFC part VG20ADC040.

Notes

• Hardcoat aluminum offers the best weight-to-wear performance; stainless provides maximum robustness at higher mass.

• As with any coated/treated part, avoid metal-on-metal scraping during installation; light lubricant on threads and bearing faces is recommended.