This guide will show you how to install the Airlab Air-Hop, an accuracy upgrade for all airsoft guns. The Air-Hop applies smooth and even backspin to the BB, providing excellent range and accuracy. It is installed into the barrel and replaces the mound inside the bucking.
This guide can also be used to install an R-hop.
You will need
- Sandpaper Strips (240 grit or similar)
- Sandpaper Sheet (240 grit or similar)
- Cotton Buds
- Thin Plastic Rod (optional)
- Multitool (optional)
- Thick Cyanoacrylate Glue (e.g. Loctite 480)
- Teflon Grease
- Thin Silicone Oil (optional)
Note: The barrel shown in this guide has been modified using the Airlab CNC machining service to increase the length of the barrel window. This is not necessary, and this guide can be used for any airsoft barrel. The machining service is only needed if you plan to use very heavy BBs.
Step 1: Select the Correct Patch
- The Air-Hop comes with 3 different size patches. One of them will be a close match to your barrel.
- Hold one end of each patch inside the barrel window, so you can see the depth of each patch in the window.
- Select a patch that is either flush with the bore, or slightly protrudes into the barrel bore
If you have an R-hop (not Z-kit version) you can skip this step.
Step 2: Cut Patch to Length
- Mark the patch with a thin marker or pencil.
- Use a very sharp knife and carefully cut the patch at 90 degrees.
- It's OK to cut the patch a little shorter than the barrel window.
- Don't leave it too long, otherwise the patch will bend.
Step 3: Sand Front and Rear Edges of Patch
- Hold the installation tool in the vise.
- Put the patch into the installation tool upside down.
- Hold the patch down with something thin in one hand.
- Use the installation tool rod with sandpaper to make a 45 degree chamfer on both edges.
- Make sure to remove all rubber particles regularly. This keeps the sandpaper cutting well.
Step 4: Remove Mound From Bucking
- Carefully turn the bucking inside out, then put it over the muzzle end of the barrel to provide rigidity.
- Use a sharp knife to remove most of the mound, leaving some material behind. (This helps ensure you don't go too deep).
- Use a sandpaper strip to remove the rest of the mound.
- Thoroughly clean the bucking with isoproyl alcohol or acetone.
- Turn back to normal.
Step 5: Sand Inside of Patch
- Use the sandpaper rod to remove a small amount of material from inside the patch.
- Keep the rod straight and level every pass.
- Regularly clean off the loose particles from the patch and the rod.
- (Optional) Use a little silicone oil as a lubricant during sanding for a smoother finish.
Step 6: Do a Test Fit
- Install the patch and bucking on the barrel.
- Insert a BB into the barrel and gently push it through with something thin.
- Pay attention to the force required to push the BB past the Air-Hop patch.
Step 7: Repeat Previous 2 Steps Until the BB Passes Through With No Resistance
- Remove a small amount of material, test fit, then repeat.
- When the BB passes through with no resistance, move on to the next step.
Step 8: Glue Patch in Place
- Clean the barrel window and patch with acetone. Make sure that both parts are completely clean and dry.
- Put a tiny amount of high quality thick cyanoacrylate glue on the barrel window flats. Don't allow the glue to go inside the barrel.
- Carefully place the patch in the window.
- Use tape to hold it in place.
- Clean inside the barrel with acetone to remove any excess glue.
- Gently insert the installation tool rod without sandpaper.
- Allow to dry for 2 hours.
Step 9: Remove Tape and Clean
- Cut the tape with a sharp knife, then gently peel it off.
- Clean off the tape residue with acetone.
Step 10: Sand Patch Flush With Barrel
- Gently sand the patch flush with the barrel.
- Sand downwards to avoid breaking the patch loose.
- Brush away the loose rubber pieces regularly.