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Madbull Ultimate 300mm 6.01mm Inner Tight Bore Barrel for Metal Gearbox Airsoft AEG ( M4 CQB, M733 )
Madbull Ultimate 300mm 6.01mm Inner Tight Bore Barrel for Metal Gearbox Airsoft AEG ( M4 CQB, M733 )

Price: $45.00

Availability:: Available Fall 2021
Product Code: MB-BARL-ULT-300MM




  • Material: Aircraft 7075 Alloy
  • Length: 300mm
  • Diameter: 6.01mm
  • Used In M4 CQB & M733 Commando
  • Hard Anodized Coating for Improved Smoothness
  • Tight Bore Barrel Upgrade
  • Improves Accuracy & Range
  • Can Increase FPS
  • Titanium Color
  • Cut for Standard AEG Hopup Chambers
  • Precision Made


The Madbull Ultimate 6.01mm 300mm barrel was made to upgrade the barrel in M4 CQB and M733 Commando metal gearbox airsoft AEGs. The Madbull Ultimate 6.01mm barrel is the smallest barrel diameter you can purchase and maximizes your performance. The tighter bore allows for better air seal down the barrel providing better range. accuracy and is some cases higher FPS. The 7075 Aircraft Alloy is super durable and is resistant to corrosion. Due to the extremely small diameter this barrel will require regular cleaning and ultra high grade BB's to prevent jamming and damage to the airsoft gun and recommended for experienced players. We recommend UAP and Bioval BB's for the 6.01 barrels for best results. For experienced players looking for every edge possible this is the perfect barrel.

Warning: We at AirRattle.com recommend all upgrade / repair parts are installed by a professional as additional upgrades and/or custom fitting may be required. It is the responsibility of the customer to ensure the part is compatible with their gun prior to purchase. We are not responsible for any damage caused during or after installation and are installed at customerís discretion.

Warning: Tight Bore barrels require the use of ultra high grade BB's like the ones suggested below. Using lower quality BB's can cause jamming and damage to your AEG.
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Average Customer Review: Average Customer Review: 5 of 5 5 of 5 Total Reviews: 1 Write a review.

  0 of 0 people found the following review helpful:
5 of 5 Madbull tightbore barrel May 14, 2013
Reviewer: Jake Brenner from St. Clair, MI United States  
It really does make a difference. I put it in my Well R20 M4 and it works great. I can notice a tighter spin on the bbs and better accuracy. Good buy.

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