Relevant Kits

The information in this article is relevant to all kits that come with either the 12.4mm or 12.9mm barrel ring. While it may be helpful kits using the legacy barrel friction ring, that is not guaranteed.

Symptoms

During the installation process, specifically while building your DGA barrel group, you attempt to the the barrel ring down your inner barrel and:

• It won't slide down the barrel at all
• It does slide, but is very tight
• It slides down the barrel, but doesn't fit over the DGA hop up bucking

Causes

A barrel outer diameter mismatch with the DGA barrel causes this issue. DGA provides two different barrel ring sizes that cover many different aftermarket and stock AEG-style inner barrels; however, DGA cannot provide barrel rings for every different inner barrel brand and type available.

Solutions

There are two different solutions:

1. Buy the DGA 12.9mm barrel ring if you currently have the 12.4mm barrel ring
2. Increase the inner diameter of your current barrel ring

If you wish to try option 2, continue reading.

Tools Needed

• A sanding or grinding tool, such as a file, a rotary tool, or a reciprocating tool
• Low to medium grit sandpaper for your tool of choice (generally 180-400 grit) - you can use higher grit grinding or sanding tools/sandpaper, but it will take longer
• Deburring tool
• A vise or clamp is helpful, but not necessary

You could also potentially use a rotary tool with a cutting bit, but this will most likely result in unintentional material removal and is not recommended.

How to Increase the Inner Diameter of the Barrel Ring

1. Place your barrel ring in a vise or clamp if available (DO NOT overtighten: the barrel ring is brass and will squish with relatively little force)
2. File, grind, or sand material from the inner surfaces of the barrel ring using even, circular motions
3. Remove any dust or debris from the barrel ring
4. Remove any burrs from the barrel ring
5. Test fit both the inner barrel and bucking in the barrel ring
6. Return to Step 2 if the ring is still too tight over either the inner barrel or hop up bucking

Alternate Drilling Method

If you would prefer to drill the barrel ring, that is also possible.

You will need to:

1. Determine the outer diameter of your inner barrel
2. Clamp or vise the barrel ring
3. Drill the barrel ring out with a bit that matches or slightly exceeds the outer diameter of your inner barrel
4. Remove material from the portion of the barrel ring that slides over the bucking (either with another bit, or with the sanding instructions above)
5. Deburr the barrel ring
6. Mount the barrel ring