.55 Boys Variation


I have a Boys round that has a projectile with a knurled canneulre. It is normal in every other sense (but it does have a brass primer), so I presume it was just a manufacturing choice of Kynoch -Yeading; K4. Is there more to it than this?



All the Boys rounds I have ever seen have brass primers.

Jyst for the record this was made about 3 miles away from where I am now. There is a supermarket (grocery store) on the site today.


Hi Paul
I can’t answer your question but I can perhaps fill in a bit of background until one of the experts come on line.
K4 Yeading Factory was situated a few miles from where I am sitting now. It was a temporary factory in every sense of the word comprising little more than a collection of huts.
I am given to believe that they also used some local engineering companies as feeders including the Rudge Motorcyle factory in Hayes (2 miles away) which was shut down during the war and turned over to war work. Probably they used the toolroom but what else its hard to say. A shutdown engineering company would have been turned over to war work but whether they were producing components for the K4 or not I don’t know. It may however go some way to suggesting an answer to your question. ie an off line production.

Factories were being turned over to all sorts of war production. The prototype and early sten guns were made in a radio factory in Perivale about three miles from there.


I do not know for details, just want to say that I have seen plenty of these knurled projectiles in the past.


Rudge Cycles (Rudge Withworth during WW I) had manufactured .303 Ammo during WW I and components; so possibly they either made the dies, or some of the machinery for making the Projectiles, or even some of the components for K4.



Thanks everyone. This variation is certainly scarce here in Canada. I guess there is no reason why any should have made their way here.

I also should have looked at my other British loads - the are all brass primered, whereas my ‘default’ setting is on Canadian manufactured rounds which are nickeled.



Hello Paul, wich is the total weight of this round?


Hi Fede,

This round weighs 118.3 g.