thanks Guys for your replies....Sorry Deejay I did not respond to your question. To answer it though no I did not purchase the chain from outdoorking. I had some master links and some offset links here to suit the heavy duty 415 chain which is why I am trying the heavy duty version of the chain. I am guessing the reason why the old chain kept throwing the master is due to old age, upon removal I will attempt a photograph and try to upload soon. Fingers crossed.
kind regards
Steve