I started doing alot of neck turning in the past year and find alot of improvement regarding flyers. This is usually with remington brass. I did a few comparisons, and found my 5 shot group size srank from ~1.5" (with flyers)to .75" consistently at 100 yards on a few loads where I had trouble some days and no trouble others.

Just curious for you guys that have neck thickness guages. Approximately, how much will your neck thickness grow with each firing. Say you start out with .015".

What I usually see is thickness varying from 13-18mil or .005" with new remington brass for my 300RUM. I see alot less variation with Federal. I try to never cut my necks less than .014" and try to stay around .015" and if one side of the neck is less than .010, I just cull it out. I heard and found out you can end up in trouble with your FL dies when you get below .011". So I want to know how much the thickness will grow with each firing from a gun like the 300RUM.

Do any of you guys with tight custom throats end up with problems from the neck thickness growing? About how many shots?