I have been training seriously for 9 months now and have made steady progress on all parts with the exception of arms.

I have been carful not to overdo the volume and frequency, I think!

Average methods for arm training are 8-9 working sets in the 7-10 rep range every 5-6 days.

There was initial growth at the start, but then boom nothing for the last 4 months or so, not a millimetre in 4 months of dedicated training and eating like a horse and consuming the hundreds of pounds of quality supplementation.

Am I just never to have big arms? Am I too impatient? Or should I get drastic and try something completely off the wall in the way of training principles?