Never used an arbor or necked turned - What am I missing here or what should I be doing differently to get more consistent ammo?
Just ordered a collet die. Waiting on
@Dthomas3523 review on the Henderson
. What else can I do?
Have AMP - CPS - FX120i.
Am not sure what you actually mean by "more consistent"??? What kind of consistency are you getting now?
You're already got some very good equipment. Neck turning will help some and the Henderson Tri-Trim is a fine tool. It'll do a great job (fast) and probably last a life time.
Looking at you procedure list, there's just a couple of things I feel could improve your results. After you anneal, I'd run the brass through the tumbler using rice (that's what I do now and it works quite well and I only run it for about 2 hrs.). Doing to removes the outside oxidation left from the annealing making for smoother sizing even though a lube is used (particularly for the inside of the neck.
You didn't say what the setup is for your sizing, like . . . are you using an expander ball in the die? If so, I'd recommend not doing so and it very often induces runout in the neck that's not there after a firing. So, use your sizing die (hopefully, not a bushing die as they too tend to induce runout in the neck) without the expander ball and afterward run an appropriate size Expander Mandrel through the neck to get neck tension your after (something like .002). Though a neck isn't turned, an Expander Mandrel will make the interior diameter of the neck uniform and move the irregularities to the outside. This all minimized runout.
Apparently, you're not uniforming primer pockets and this can be a substantial issue depending who's brass you're using. Quality brass will have less variance. If you're only seating the primer to the depth of the primer, you're not getting any primer crush. Once will get better consistency with some primer crush so that the primer anvil is firmly against the bottom of the primer pocket. .003 of primer crush is what many do. Measure the depth of your primer pockets and seat the primer .003 further than the primer's height.
I often get very good accuracy by seating .010 off the lands, but it all depends on the bullet and the particular powder you're using. It's not usual to find best accuracy from .025 to .050 off the lands. One just needs to experiment to see just does best. There's a
series are articles here that has a lot of great information about this.
More improvement can be realized by sorting the brass by weight and use the few outliers for sighters. Also, measuring and sorting bullets from base to ojive (BTO) to get consistent seating depths. Usually with quality bullets, this may not be necessary, but it good to at least sample your lot of bullets to be sure there's not a significant variance. If there is, then sort them by +/- .002. or less.