SixG HSB – High Speed Buffer

UPDATE 06/04/2022: Now In Stock!

Snappier firing and better control for high power gas use

Our simple yet effective High Speed Buffer (HSB) spacer serves to reduce semi auto shot cycle time, manage recoil energy when using high power gas & give better shot consistency.

We love a TM MWS and its definitely a hard gun to improve on from standard, but we endeavor to increase the performance and realism of this great GBBR, no one really owns a GBBR for an insane rate of fire, but for the realism and performance it gives on semi auto – so we have spent a lot of time trialing different preloads and other recoil buffer springs to make our SixG HSB spacer a product that works and is an improvement over the original.

The SixG HSB spacer is designed to improve the overall performance of the gun and to protect the buffer – especially when using high power gas, it is not intended to increase recoil.

UPDATED 01/03/2022: VERSION 3 HSB Spacer – has a slightly reduced overall length, this was to strike a balance between the V1/V2 performance gains whilst allowing it to be used in conjunction with standard and heavy bolts alike.

UPDATED 12/05/2020: VERSION 2 HSB Spacer – incorporates rubber bumper and is finished in chemical black for corrosion resistance.


SixG HSB Spacer performance benefits:

  • NEW – rubber bumper provides soft impact for the end of stroke bumper, further reducing the possibility of a shattered “buffer part B”.
  • Reduced shot cycle time – hence the name ‘High Speed Buffer’ – bolt carrier group (BCG) returns to battery faster ready for the next shot.
  • Increased buffer spring preload and progression control excess recoil energy when using high power gas – protecting the gun from violent shock and vibration, without the penalty of high gas consumption that stiffer buffer springs use.
  • Typical 8 FPS power increase over standard buffer spring only.
  • The increased preload along with the faster return to battery seats the nozzle into the bucking firmly for a better gas seal.
  • Still utilizes the MWS end of stroke bumper.
  • Installs in seconds – no tools required!
  • Chemically blacked for corrosion resistance
  • And the best bit… reduces the MWS recoil ‘twang’ in your ear!



Standard MWS – 104 BBs on single gas fill – Abbey VERTEX – 18c ambient temp

Standard MWS shooting test video – opens in new tab/window

SixG HSB spacer – 99 BBs on single gas fill – Abbey VERTEX – 18c ambient temp

SixG HSB spacer shooting test video – opens in new tab/window

As can be seen gas consumption increase over standard buffer spring is only 5 BBs per single gas fill, realistically in play you would not run more than 2 full loads (70rds) on 1 gas fill so the consumption is nullified.


Standard MWS – Baseline figures on 0.2g BB


Standard MWS with SixG HSB spacer – Comparative figures on 0.2g BB


  • Faster semi auto ROF – due to faster return to battery
  • Slightly slower full auto ROF – due to increased work (stiffer recoil system)
  • Increased FPS due to nozzle bucking seal improvement – typically 8 FPS, full auto FPS is not accurate to measure.
  • Increased shot FPS consistency due to nozzle bucking seal improvement

To fit the following models;

  • Marui GBBR – CQBR / BLOCK 1 MWS
  • Marui GBBR – M4 MWS
  • Marui GBBR – M4A1 Carbine
  • Marui GBBR – MTR16

HOW TO PURCHASE: SixG HSB Spacer £31.00 including UK mainland delivery.

We have now teamed up with airsoft store Leadfoot SixG as an official stock holder to allow you an easier order process and the opportunity to order other relevant items for the MWS, so please click the link to visit them and place your order!

If you have any technical queries or wish to order directly then please email us with your order, we will require your full name and delivery address confirmation, overseas orders will also need an email address.


  1. Remove magazine
  2. Check bolt is forward / pull trigger with fire selector on SEMI
  3. Pull rear receiver pinIMG_3315
  4. Open upper recieverIMG_3316
  5. Push buffer spring retaining block downIMG_3318
  6. Release and remove buffer springIMG_3319
  7. Push in SixG HSB with rubber bumper facing towards butt stockDave_gunPart
  8. Lubricate spring with supplied Moly-slip grease re-fit
  9. Close reciever
  10. Re-fit rear receiver pin – GOOD TO GO!

3 thoughts on “SixG HSB – High Speed Buffer

  1. Works a treat! Superbly made. Made my mws very snappy, Been using for the last 5 months with no issues! Would recommend if your looking to up your cyclic rate.



  2. An incredible upgrade that makes the MWS all the more snappy and responsive. I thought that it might be problematic paired with my aluminium BCG, but it positively locks back every time the mag is empty! Extra appreciation to Dave and his friendly advice over email.


  3. Good product and a worthy upgrade for any MWS. I run an AngryGun buffer and aluminium-bolt, works very well and reduces this nasty spring noise.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this:
search previous next tag category expand menu location phone mail time cart zoom edit close