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.

For more on the L119A2, check out my article here.

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