Brass worked harder with full length resizing with or without sizer button

Ruttinbuck

Ruttinbuck

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I'm changing my resizing process and looking for some opinions on what works cases more causing work hardened brass sooner. I'm seeing unexplainable flyers when load testing and changing dies is my next step to try. I'm a hunter but appreciate quality hand loaded ammunition so care is taken every step of my ammunition building to get consistent results.
I'm just ordered some 21st century innovations mandrel and expander dies to get more consistent neck tension and runout. I've been using RCBS and Redding FL dies for the calibers I'm loading 260 rem and 7mm-08 rem. My brass is remington for the 260 and WW, Hornady for the 7mm-08. I'm annealing before every reload on the remington brass and will be before the next reload of the 7mm-08 brass. The brass gets the full prep work out, with primer depth uniformity,flash hole deburring,trimming every load etc.
From what I've been reading to use the mandrel neck sizes you should 1st decap then FL resize with the expander stem removed to minimize the working of the neck brass. I get the theory and don't disagree. But...with this process the neck is sized smaller than with the expander and will be worked considerably harder by the mandrel as it forces the inside of the neck back open to its diameter. Would these two steps induce roughly the same amount of work to the neck of the brass?
Or should I be looking for a dedicated decap die and start doing another step in my brass prep to eliminate the expander ball through the neck all together?
Any input is appreciated RB
 
Step one: the die sizes the neck small.
Step two: the expander ball opens neck from that size to finished size.

Or

Step one: die sizes neck down.
Step two mandrel opens neck up to finished size.

Theoretically same work.

If you go die, ball, mandrel, you will be working the brass more. 1 crush neck, 2 size and springback neck(ball), 3 size and spring back again (mandrel). More cycles on the brass, and youre still dealing with a potentially off center ball. Good chance the expander ball is going to be negating whatever you're trying to achieve with the mandrel. You would have to mic the expander ball and see if it is smaller than the mandrel, as it could be bigger, and then the mandrel is kind of a waste.

I run a separate decapping die, and i do curse the extra step. I always debate grinding a expander ball down so that it doesn't interfere with the sized neck, and then reinstalling it so that I can size and deprime in one step.
 
Thx for the input. I had thought about sizing down one caliber on the expander to lessen the brass being worked but it's still being worked.RB
 
I use Forster dies that have had the neck sizer portion custom honed (opened up) by Forster. As long as you are using the same brass for reloading ( case neck wall diameter is the same) these have way less neck sizing therefore the expander ball is also doing less.
 
Bad Bob- the lee collet was a consideration but thought the 21st century mandrels were a better option as I was buying for two calibers and two different neck diameters.
One die 4 mandrels .002&.003 neck tension.
Poffels-considered Forster dies,decided mandrels were be tried next.
Dindunuffin- I'm annealing every load as well to help consistency
Boxhitch- lapua and nosler are considerations but I have 150 new remington and 250 new WW & Hornady cases already so until I run outta options these brass are it.
thx for the input gentsRB
 
Are your case necks all the same thickness [between cases] & the same thickness all the way around [on 1 case]?

I use a Lee decapping die as the first step.
Then I wash the brass.
Then I use a full-length bushing sizing die, so I'm not overworking the neck.
Alternatively, for a few of the cartridges I load for [.223, 6.5CM & .308 WCF] that are used in a single rifle, I use a neck-sizing bushing die, usually Redding.
I use a Redding Match grade powder measure, at least with ball powders.
When seating, I use a straight line seater, either a Wilson, a Forster or a Hornady.

Also, as has been alluded to above, GIGO [Garbage In, Garbage OUT!]

Your fliers could be caused by varying case capacities, creating higher pressure in some, lower in others. As you are, no doubt, aware, pressure determines velocity [within the same cartridge, using all the same components] which results in differing POI's.

They [the fliers] could also be the result of inconsistent primer seating, varying firing pin spring tension, a too-sensitive powder charge, poor QC of your chosen bullets, bullet run-out, &c., &c., &c.

Lapua makes brass for both the .260 Rem. & the 7mm-08. Unfortunately, they are all LRP. You could size their .308 WCF SRP down to the required size. The benefit to that is that your neck thickness will be greater, allowing you to turn your case necks for a tight neck, if you are comfortable with that & are aware of the requirements when using tight-neck brass.

My $0.02 Cdn.
 
Jamesharrison-as best I can see with my case master tool the necks are pretty consistent thickness wise. My brass are weight sorted under 1% or less. I water capacity tested 2 different cases and got the same result so didn't take anymore time on that. Last time out shooting I separated the cases that produced fliers and found the runout was .004-.006 on them. I was able to get them under .003 when resized by turning them multiple times in the resizing die. They were annealed before resizing and seem to be not returning to .004+/- runout as they await reloaded again. At this time I'm not considering neck turning for a 7lb hunting rifle. RB
 
Sounds like you've covered a lot of bases already. How about trying, when you are seating the bullets, seating them half-way, then lower the press handle, twirl the bullet 180 degrees & seat them the rest of the way. Does that make any difference in your runout?
Is your press ram clean on its top? Is your shell-holder clean in its rim recess? Have you got other shell-holders that are the same size? If so, have you tried those to see if there is less [or, hopefully not] more runout?
Have you tried measuring the runout on your fired cases? If so, is it better or worse than the runout of your sized cases? Better than the runout of your loaded rounds?
 
I practice alot of what you have mentioned. I'm going the mandrel route to see if better consistent neck tension from the mandrel will help with the fliers and of corse less work on the necks. Most people say the ES will improve with the mandrel use as well. Appreciate your input RB
 
Ruttinbuck said:
I practice alot of what you have mentioned. I'm going the mandrel route to see if better consistent neck tension from the mandrel will help with the fliers and of corse less work on the necks. Most people say the ES will improve with the mandrel use as well. Appreciate your input RB
Click to expand...

I decap with a hand held unit. Very quick and easy. Then clean the primer seat area, and anneal. Then size FL size my brass with the expander ball removed, then clean all my brass. After brass is clean I run the mandrel to expand the necks and then they ready to reload. I find the xpander mandrel runs smoother in the cleaned brass than running it before the cleaning. Gets some crud built up on it otherwise. (carbon)

If your new process doesn't produce better results, either go new brass, if possible lapua, peterson, or alpha. Even Starline will be better.

If all above doesn't produce, then I would look at your press, or powder process.

My last unexplained fliers were in 450 BM. I had 3D printed an adapter to the funnel to drop powder in cases and found that the powder was sometimes sticking in the adapter with static, so different amounts were dropped in different cases. Hard to find a proper funnel for larger brass. Totally not consistent. Drove me nuts looking for the problem, and then one day I happened upon it when loading some rounds. Bingo, problem solved. Now I tap each powder drop to clear the funnel adapter.
 
Update 260rem
Bought some Peterson lrp brass. Forester ultra micrometer seating die. Ran the brass through FL die without expander then .2620 mandrel for to get neck runout around .001" and neck tension at .002". The forester die gives consistent seating depth results with minimal runout. Shot groups at 2 different powder weights and 4 different seating depths. I had 3 shots outta 32 that the chrono said were 30-50fps higher than the rest but they didn't impact on target as flyers.
2.55" BTO COAL 2.76" starting point
8 groups of 4 shots H4350 WLR primers
43gr 2.250" BTO 2825avg ES43
43gr 2.245" BTO 2812avg ES 20 3 in.8"
43gr 2.240" BTO 2827avg ES 12 3 in.78"
43gr 2.235" BTO 2829avg ES 66
43.3gr 2.250" BTO 2817avg ES 17
43.3gr 2.245" BTO 2843avg ES 50
43.3gr 2.240" BTO 2826avg ES24 3in.176" 4 in .78"
43.3gr 2.235" BTO 2829avg ES 15
Will be loading the 43&43.3gr 2.240"BTO again and see if it will repeat. Quality components and equipment makes a big difference. Thx for your input gents RB
 
Once you confirm your results are repeatable, and not an anomaly, then it's time to compare different lots of your chosen projectile, then different primers, then different lots of your chosen primers, then different powders, then different lots of your chosen powder! Oops, time to re-barrel as you've burnt out your barrel. Back to square 1!

Still having fun?

;-)
 
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