It sounds like you're simply used to a lot more leverage from your Rockchucker, and if you're not chamfering the inside of the case mouths and/or lubing the inside of the necks before seating bullets, then seating bullets with an arbor press's little handle is going to take some elbow grease. And you can see the damage from the wet tumbling starting at the case mouth in your pic. IMO wet tumbling is for blaster ammo only, never for precision cases (especially twice per load cycle, sheesh).
Precision Seating Die Options
- Thread starter bbowles
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It sounds like you're simply used to a lot more leverage from your Rockchucker, and if you're not chamfering the inside of the case mouths and/or lubing the inside of the necks before seating bullets, then seating bullets with an arbor press's little handle is going to take some elbow grease. And you can see the damage from the wet tumbling starting at the case mouth in your pic. IMO wet tumbling is for blaster ammo only, never for precision cases (especially twice per load cycle, sheesh).
Haven't got my Sinclair Wilson seater back but I did check on Bullet Central's site and they got the Micron arbor seating die back in stock. I couldn't resist. So I bought it and same exact bullet runout as with the Wilson. Man is the Micron slick! But same results. My old Redding Comp seater die gets about 0.002 bullet runout all day and these arbor dies .0035 to 0.004.
So I dug out my Redding S type sizing die with a .290 bushing and the carbide expander ball. It never produced less runout as my Forster Honed .289 sizer. The Forster always has 0.001 or less neck runout and 0.002 bullet runout.
Interesting thing happened when using the Redding sizer die. Now I couldn't even get the sized brass to go all the way into the Micron seating die. And when I did get it in there I had to dig it back out. And same 0.0035 bullet runout. So I kept sizing another 10 pieces with Redding bushing die but seated with Redding comp die. 0.002 bullet runout or better! However, these were MUCH harsher to seat despite about same tension.
So my questions are why did the Redding sizer not size down enough to fit in the Micron seater? Why were Redding bushing die sized brass seat much harder? And why do arbor seating die systems produce significantly higher bullet runout?
My 6.5 Creedmoor is a Match chamber. Sorry for the rambling. Thanks for the input?
So I dug out my Redding S type sizing die with a .290 bushing and the carbide expander ball. It never produced less runout as my Forster Honed .289 sizer. The Forster always has 0.001 or less neck runout and 0.002 bullet runout.
Interesting thing happened when using the Redding sizer die. Now I couldn't even get the sized brass to go all the way into the Micron seating die. And when I did get it in there I had to dig it back out. And same 0.0035 bullet runout. So I kept sizing another 10 pieces with Redding bushing die but seated with Redding comp die. 0.002 bullet runout or better! However, these were MUCH harsher to seat despite about same tension.
So my questions are why did the Redding sizer not size down enough to fit in the Micron seater? Why were Redding bushing die sized brass seat much harder? And why do arbor seating die systems produce significantly higher bullet runout?
My 6.5 Creedmoor is a Match chamber. Sorry for the rambling. Thanks for the input?
Sorry for that long winded post. Anyone have any suggestions as to why the arbor press seater setup (k&m press with both the sinclair/Wilson and the Micron arbor dies) is almost double the runout of the Redding Comp seater on conventional press? 0.0036 mean vs 0.0020 bullet runout? Have now tried right at 125 rounds with both methods.
I am not chasing low bullet runout only. I really want to like the arbor press route since I have learned a lot already about seating pressures. Seating starts at 20 psi and fully seats at 30 to 35 every time! Like butter. Only time it was twice that was using Redding bushing die for sizing. It took a lot more pressure to seat. Could feel this same thing with Redding comp seater on bushing sized brass.
I would just simply go back to what has worked for years but this has just got me puzzled.
I am not chasing low bullet runout only. I really want to like the arbor press route since I have learned a lot already about seating pressures. Seating starts at 20 psi and fully seats at 30 to 35 every time! Like butter. Only time it was twice that was using Redding bushing die for sizing. It took a lot more pressure to seat. Could feel this same thing with Redding comp seater on bushing sized brass.
I would just simply go back to what has worked for years but this has just got me puzzled.
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The honed Forster .289 results in less seating force than the Redding S-type with a .290 bushing + expander ball? Are you using the expander in the Forster? If not, remove it from the Redding and see if the seating force results start looking similar. The difference in expanded neck ID would explain the difference in seating force.
As for runout, if you want to keep experimenting with it, neck turn or skim turn (uniform the neck wall thickness a little), then size using both methods and see what results you get. Your runout is going to be dictated by the uniformity of the case neck. Only thing I can think of is the floating sleeve/press mounted style is allowing the bullet to compensate for the bullet neck wall thickness variation that a no-float/chamber type bullet seating from an inline die will not do.
It's possible. Could be a neck wall thickness issue, could be a sizing issue, etc. Swap to a .289 bushing and see if that changes it.
As for runout, if you want to keep experimenting with it, neck turn or skim turn (uniform the neck wall thickness a little), then size using both methods and see what results you get. Your runout is going to be dictated by the uniformity of the case neck. Only thing I can think of is the floating sleeve/press mounted style is allowing the bullet to compensate for the bullet neck wall thickness variation that a no-float/chamber type bullet seating from an inline die will not do.
Have tried the Redding bushing die many times over the years. With Ti bushings, steel bushings, carbide expander ball, steel expander ball, and even no expander ball.
Results were always higher runout and much harder seating pressures.
The Redding bushing die actually yielded .2915 OD sized necks, .2927 loaded neck OD for tension of only .0012.
Forster .2907 OD sized necks for a tension of .0020. Twice the tension but half the seating pressure. Makes no sense but it's what it is.
Setting the Redding bushing die aside and using the Forster to size because it works. What is weird is seating with both the Micron and Wilson arbor dies yields twice the runout. However, as long as I size work the Forster both arbor dies and the press mounted Redding comp seater die are butter smooth. The arbor dies are just twice the runout.
I have ordered Lapua and alpha brass and will test again.
Really appreciate helping me think through this. Will update as I can.
Results were always higher runout and much harder seating pressures.
The Redding bushing die actually yielded .2915 OD sized necks, .2927 loaded neck OD for tension of only .0012.
Forster .2907 OD sized necks for a tension of .0020. Twice the tension but half the seating pressure. Makes no sense but it's what it is.
Setting the Redding bushing die aside and using the Forster to size because it works. What is weird is seating with both the Micron and Wilson arbor dies yields twice the runout. However, as long as I size work the Forster both arbor dies and the press mounted Redding comp seater die are butter smooth. The arbor dies are just twice the runout.
I have ordered Lapua and alpha brass and will test again.
Really appreciate helping me think through this. Will update as I can.
received Lapua and Alpha brass and sized again with my Forster honed die because I know it works. Sized both virgin Lapua and Alpha and once fired. Interesting stuff. The Lapua was considerably more concentric in both neck and bullet runout than Alpha in both virgin and once fired. Also, my old trusty Redding Comp seater was great as normal with .002 or less bullet runout but the Micron and Wilson/Sinclair seaters were again double the bullet runout without fail. Not one sample have I received lower bullet runout than my Redding. I even sent back my Wilson to them to check it out with some of my brass and Berger 140 hybrids and Hornady ELD bullets. They replied back with a note in my die and components that they replaced the VLD Stem and was now getting .002 or better runout. Not trying to bad mouth at all but on my Accurace One Concentricity guage I tested my Nosler brass and both bullet brands that they had used their Wilson arbor die on. I showed .0035 bullet runout. I know there can be differences but that is same runout I was getting with my components and their die. So nothing has changed. I guess I will either let my K&M arbor press and both Micron and Wilson dies collect dust or sell them. I tried every combination I could think of and always the same. My Forster die gets barely over .0005 of neck runout and the Redding Comp die on my Area 419 press gets .002 or better bullet runout. Was actually fun experimenting but I have a great process already and will run with it. Thanks for all the input.
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