For those interested in the R4 bayonets. There are 3 main types.
1 - That KCB77 trials one that was never really used, and sold off by LIW, that had a barrel attachment to give the R4 a bayo lug so that the regular KCB77 AR15 bayo could be fitted. I am not going to address that one again here, it's not really official issue, but will try and cover it sometime soon with pics.
2 - The true R4 bayonet commissioned for use in riots and railway station protection by one unit of the army, with a hardened steel tube inside, and the new long catch. This one is also known, and rare but is covered well on the net already. It was designed because although the R4 muzzle break would fit inside the R1 bayonet, even with a hardened steel tube inside to bring it back to the point that the R1 catch would hold it in just behind the flash hider, it would still rotate at will. And that wasn't acceptable to those who requested this bayonet be developed. So the longer catch locked into the flash hider slot, and prevented the bayonet from rotating. (I have one for sale for $400 if anyone is interested)
3- This is the one that is the subject of this post. This is the one seen in a few pics of troops on parade, that look like they have R1 bayonets fitted. There is a hardened steel tube inserted and fixed permanently inside the bayonet. This closes off the R1 flash hider slots, and also lets the R4 muzzle break stop inside, to the point that the R4 muzzle break sits where the R1 catch will just nicely lock in behind it, and keep the bayonet secured.
Yes, the bayonet can rotate, but it fits securely and locks on.
Often confused with the regular R1 bayonet, the steel tube blocking the slots gives it away.
I have taken a pic showing an R4 muzzle break on the outside of the bayonet where it would sit inside. Then a pic of the muzzle break being inserted, and then one where the muzzle break is inside the tube, and locked in by the R1 bayo catch.
No idea how many of these were made, but suspect not many, and only for parades.
Hope this helps those interested.
The "other" R4 Bayonet.
Moderator: Mr. B.