Hello,

I have seen numerous times a nozzle temp reading 450F, but actually 550F, and causing those issues with ABS. I agree with Bryan, and suggest taking a temperature probe, and sticking it inside the nozzle to see actual temp, (also inside hot sprue/manifold if your mold is so equipped.)

Second suggestion, 430F sounds too cold for ABS, I run it at least at 450F, and too cold can also cause splay.

Joel