Symptoms

This issue manifests in two ways:

• Much lower than expected muzzle energy/velocity
• Chopped BBs and/or inconsistent feeding

The first symptom is, of course, the most pronounced. It may be accompanied by the second, but not always.

While users sometimes encounter this issue with standard power kits, it is much more likely with low power kits (either purchased as a kit, or with a separately-installed low power airshaft).

Causes

The most likely and common causes for low muzzle energy on a DG build include:

• Air leak in the system
• Airshaft battery position too far back
• BB pushed too deeply into hop up bucking
• Damaged hop up bucking
• Using an SLP HPA tank
• Short inner barrel
• Low input pressure
• Hop up bucking not flush with chamber
• Airshaft crush ring or spring worn or damaged

Solutions

Here are a few general tips:

• Short inner barrels (<300mm) will struggle to achieve a high muzzle energy even with a standard airshaft. For example, builds like the VFC MP5 using a 208mm inner barrel will often only shoot at around 1J-1.3J at 120PSI
• Try setting your regulator to 120PSI
• New builds may require some breaking in. Try firing at least 2-3000 BBs through the gun to see if it makes a difference
• Full auto fire often has a lower muzzle energy than semi, due to system operation

Click to open the flowchart.

 

Do you need to move your airshaft collar? Check this link.

Do you need to try the Teflon Mod? Check this link.

Do you need to widen the holes on your airshaft? Check this link.

Do you need to get a flush fit with your bucking and chamber? Check this link.