Leaked pic showing the two Colt Canada-style receiver extension nuts that HAO will be offering shortly; as part of their L119A2 Full Kit and as separates:


As an alternative to the RS – which isn’t easy to source – this is great news for those out there who have L119A1 or L119A2 replicas, which use RS threaded buffer tubes.

HAO has decided to do the three stake version as well as the more modern four stake model, since apparently both are in circulation (and exhibit the same Colt Canada product number). ‘Stake’ refers to the staking notches arranged around the nut’s circumference, which help prevent loosening.

The Colt Canada receiver extension nut is a bit different from the current Colt ‘castle nut’ (as depicted by most replicas) and has been noted as one of those unique features which help define the L119 series.

A contemporary Colt castle nut is shown below, with an RS Colt Canada receiver extension nut for comparison.


The Colt Canada design is actually an older one, which Colt no longer uses. It is said to have been retained by the Canadian military, so as to present fewer sharp edges to the user – so as not to foul gas masks.

Keep your eyes on HAO’s website to see these drop. They’ve created a new L119A1/L119A2 section here.

hao a1 a2

Part 2 of this series can be viewed here.

Oh, and there’s also these selector sets for PTW:


Catch up on the full HAO IUR series here.

More articles relating to the L119A2:

  • The original L119A2 primer, here
  • GG&G AR15 vertical fore-grip in use here
  • Magpul QDM and ASAP QD in use here
  • 15.7″ L119A2 upper in use here
  • Surefire FA556SA Suppressor here
  • GG&G Aimpoint T1 mount in use here
  • Magpul MS3 sling in use here
  • Magpul ACS stock in use here
  • Colt Canada parts – as used on the L119A2 – here
  • Manta Very Low Profile Rail Covers as used on the L119A2 here
  • UKSF Newcastle raid pics part 1
  • UKSF Newcastle raid pics part 2
  • UKSF Nairobi Kenya incident L119A2 parts breakdown here
  • UKSF Belize ‘Jungle Set-up’ L119A2 parts breakdown here
  • Confirmation bias (and the HSP Thorntail offset light mount) here
  • UKSF Ecosystem: S&S Precision Sling Clip – Old Gen – here
  • Inforce WML-type lights in use here

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Obi Wan Nairobi patch from Platatac