Muzzle Velocity Rules and DMR Rules
NO C02, HPA OR POLARSTAR TYPE GUNS ARE ALLOWED AT TECH BRIGADE! This is not open to debate. Please don’t ask.
- What is Muzzle Velocity and Why Does it Matter?
- Auto Electric Guns
- Gas Blow Back Rifles
- Spring Bolt Action and Gas Bolt Action Rifles
- Designated Marksman Rifles
What is Muzzle Velocity and Why Does it Matter?
Muzzle velocity is the speed at which a BB leaves the barrel of an airsoft gun. It is measured in fps or “Feet Per Second” in “old money” or in meters per second (ms-1) in modern SI units. We need to know what the muzzle velocity is as it is the easiest way to measure the energy of the BB leaving the barrel, or Muzzle Energy. We need to know the muzzle energy as, from the 2nd May 2017, the Policing and Crime Act 2017 now legally defines the maximum muzzle energies airsoft guns are allowed to use.
Muzzle energy = 1/2mv2
m = the mass of the BB in kg
v = the velocity of the BB in meters per second (ms-1)
If the mass of the BB is 0.0002kg and the velocity is 100ms-1 then the muzzle energy is 1 Joule.
100ms-1 = 328 fps
The new legal limits are:
- 1.3 Joules for fully automatic airsoft guns = 374.07fps / 114.02ms-1 with 0.20 gramme BBs.
- 2.5 Joules for single shot /semi auot only airsoft guns = 518.74fps / 158.11ms-1 with 0.20 gramme BBs.
These are now the MAXIMUM Legal Limits. Exceeding these limits can have very serious consequences. For safety reasons, and to comply with our Insurers requirements, we will be sticking with the fps limits we used prior to the PCA coming in to force.
Automatic Electric Guns
Fully Automatic Electric Guns will have a muzzle velocity of no more than:
- 350 fps with 0.20 gramme BBs.
Whether semi or full auto, AEGs (and AEPs) will have a muzzle velocity of no more that 328 feet per second (muzzle energy max 1 Joule) with a 0.2g BB. The only exceptions are those rifles which meet the specific requirements of DMRs below. We allow a 7% variation, BUT, that is leeway to allow for atmospheric conditions, not a blind eye to guns intentionally built to fire at 350.9 fps. A chronograph is available to double check your weapons.
Gas Blow Back Rifles
Gas blow back rifles will have a muzzle velocity of no more than:
- 350 fps with 0.20 gramme BBs.
Gas gun users near the upper limit must be aware of increases in temperature affecting the fps of their weapons.
Spring Bolt Action and Gas Bolt Action Rifles
Bolt action weapons will have a muzzle velocity of no more than:
- 500 fps with a 0.20 gramme BB.
Designated Marksman Rifles (DMRs)
Designated Marksman Rifles will have a muzzle velocity of no more than:
- 425 fps with 0.20 gramme BBs.
You may use a DMR type rifle as long as it falls within the following criteria:
- It has to be ELECTRIC and NOT gas powered (GBB rifles will still stay within the AEG fps limits)
- It MUST be locked to SEMI AUTO only with the full auto capability REMOVED or DISABLED.
This is now a legal requirement.
- DMRs must be checked by Rob and no-one else prior to any use in a skirmish.
You may use one of the following types of rifle as a DMR. Anything else please ASK FIRST! Souped up M4s do not meet the requirements for a DMR at Tech Brigade.
- M14 (not the SOCOM version)
- G3 SG1
- VSS Vintorez
This covers a broad spectrum of real steel DMRs and should fit with all types of load outs.
These are maximum FPS figures, not 1 fps over.