Thread: Case neck sizing and effect on accuracy

I have just started neck sizing for my 243 after full length for years. Taking careful measurements the difference between the bullet diameter and the neck sized is 2 thou. does the full length sized give more neck tension? I measured maybe 3 thou. Im using lee dies but felt the bullets could still be pushed further in by hand if I was rough with them after neck sized so I bought a lee crimper. From shooting at the range not much difference in group sizes between the 2 loads. Gun is a Remington SPS in 243. Need to start with new once fired brass and start again maybe the brass has gone hard in the neck and need annealing which I haven't had a go at yet. Any input or advice?