Barrel Lapping Service


We are offering a lapping service for your barrels! Instructions to send in at the bottom.


What is it? Its a grinding method to microscopically remove material from the surface of the bore. Using extremely fine diamond compounds, we can remove material from the inside of the barrel that is uniform and consistent throughout the bore. Leaving a mirror-like finish that's very time consuming to achieve on a steel barrel.

As a result, the following happens.

  • ~2% increase in FPS
  • Increased shot to shot FPS consistency
  • Increased accuracy downrange
  • Easier barrel cleaning/less stubborn residue buildup

Below is an example of a Prometheus Barrel 6.03mm, pits, and bore marks can be seen within the barrel. With lab instruments we've measured this low/high spread as 5 microns. These microscopic holes tend to catch BB residues, and increase the internal friction of the barrel slowing down the BB.

Below is that same barrel with our lapping process done to it. We're able to reduce the internal bore surface roughness to below 0.5 micron. Resulting in a mesmerizing mirrored effect on the inside.


  1. Print out your order after checkout.
  2. Securely package your barrel and include order in your box. 
  3. Ship to:
    Umbrella Armory, LLC
    3857 Schaefer Ave
    Suite H
    Chino, CA 91710

    This purchase price includes return shipping to you already for those in the CONUS (though select any shipping speed you'd want to pay for). We will return your barrel once it arrives to us in 3-4 weeks.

Customer Reviews

Be the first to write a review