Bullet Runout Issues - Help!

cjc5062

FNG
Joined
Nov 30, 2020
Messages
35
Location
Cincinnati, OH
Hi all, so I’ve completely gone off the deep end the last few months with precision hand loading. I don’t shoot PRS or anything, but do go out west to hunt every year and shoot often. I enjoy trying to get the most precise loads and accuracy out of my hunting rifles and am just trying to learn as much as possible. I’m focused on 6.5 PRC and 7 PRC at the moment.

In the last few months I have completely upgraded my reloading set up. I’m now running the following setup: Area 419 Zero 2 Press, Area 419 Full Length Micrometer Sizing Dies, Short Action Customs Infinity Arbor Seating Die, Amp Mark II Annealer, Amp Press, Henderson Trimmer, Primal Rights Primer, Ingenuity Precision Powder Trickler with Sartorius Scale, Mitutoyo calipers, Mitutoyo micrometer, Area 419 comparator set, Area 419 Powder Funnel and tube extensions, Accuracy One Concentricity Guage with Mitutoyo dial, and other odds and ends items. I have not yet purchased an Autodod case neck turner, but it has crossed my mind.

I have watched just about every video I can out there, including Primal Rights, Ultimate Reloader, Bolt Action Reloading, F-Class John, etc. and have tried my best to use the same processes in start to finish reloading. I’m currently using new Peterson Brass (sorted to .005” - <.001” neck concentricity), anneal first, then trim/chamfer, brush inside of the neck with nylon brush, powder charge, seat bullet.

I have been able to get down to very good Standard Deviations in my loads (some as low as 3 fps Standard Deviation for 3 shot groups), but cannot for the life of me get consistent or acceptable bullet runout. I’m using Berger Elite Hunter bullets in 140gr. for 6.5 PRC and 175gr. for 7PRC. I take my measurement of bullet runout halfway between the neck of the case and end of the bearing surface (before bullet starts to angle down). My bullet runout measurements range anywhere from .002” to .008”. With the quality of components and tools I’m using, I’m really hoping to get the runout to around .0005” but at this point would take anything less than .002”. I think I may have narrowed this issue to a few things, but would like to get other’s thoughts before I go trying other things:

  1. Short Action Customs Seating Die – I’ve heard mixed reviews on the SAC Infinity Die, in that there is too much movement since it is made for any caliber. Thinking of trying Micron dies or anything else that is highly recommended for precision.
  2. Henderson Trimmer – The pilot on the Henderson trimmer, while it doesn’t seem to do much to the inside of the neck when trimming/chamfering, I know Primal Rights states the pilot trimmers can impact seating. Although, I know this trimmer is highly regarded by many and used without issue.
  3. Change the lubrication for sizing – I currently use Hornady One Shot for lubrication, but this does not necessary get inside the neck well. I’ve heard many shooters using imperial wax as the main lubrication of choice.
  4. Neck turning – I have not yet purchased a neck turner, although I’m considering an Autodod. However, in watching various videos, I know getting <.002” bullet runout is very doable without neck turning.
Please let me know if there is anything that stands out to anyone, or if there is something I’m not thinking of. I know bullet runout may not impact accuracy all that much, but its more about the pursuit of trying to get the most out of my loads. It’s also just driving me absolutely crazy lol
 
Are you taking measurements throughout the process? For example, take measurements of unsized brass, after sizing, after seating, etc. I'd even take measurements of factory ammo to get warm fuzzy on your measurement technique.
 
Are you taking measurements throughout the process? For example, take measurements of unsized brass, after sizing, after seating, etc. I'd even take measurements of factory ammo to get warm fuzzy on your measurement technique.
Yes, I take measurements at all stages. Before doing anything, after resizing (including inside diameter) and after seating.
 
Yes, I take measurements at all stages. Before doing anything, after resizing (including inside diameter) and after seating.

Where do you see your runout growth? Like is it low low low high? Low low high high? Your measurements at different phases will identify which process is introducing the variation.
 
The more the case neck grips the bullet the worse runout will be - that can be uneven or lacking lubrication or sizing it too small and requiring the neck to grow a great deal. Annealed or not, some brass will have hard and soft spots - I toss brass if it caused a flier because there can be all sorts of hidden defects working against you. A Wilson seating die and arbor press are what often works the best and those universal seating dies have too many tolerances that get stacked against you. Culling finished ammo with large runout is also just a normal part of reloading - expecting all ammo to be perfect isn’t realistic. I set it aside for fouling shots or offhand practice and mark the case head with a tiny scratch going from primer to edge of rim - anything can be used from a sewing needle, to utility knife blade, to one of those carbide scribers made for marking metal - just a very light scratch. If it continues to have excessive runout a second time it gets tossed.

All this is dependent on what you’re shooting - if you have a factory barrel that shoots above 1/2 MOA I don’t think using the best methods will buy you much. My personal cutoff is 1/2 MOA. Larger than that and I just use regular old school full length sizing die sets unscrewed half a turn so they more or less only neck size - $29 used on eBay. Smaller than that I’ll use a fl bushing die unscrewed 1/2 turn to more or less neck size and separate expander mandrel, paired with Wilson seating die.

Sounds like you’re headed in the right direction.
 
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