Nonsensical Headspace Measurements on 223rem cases...??

[markm]

Using a case gauge is fine for hoser ammo, you are just verifying that is will chamber.

I load precision .223 all day long and never owned or used anything other than a gun's chamber or a case gauge. I have NO problem at all using/getting equipment to make precision ammo or adding steps to the process. But there needs to be a payoff of some sort. I need a reason to be doing extra leg work.

Neck tension is the key.

I think I'm getting neck tension consistency from the LEE Factory Crimp Die. I know it dramatically increases accuracy for me, but I'm only guessing that it's due to neck tension uniformity.

You don't really need to crimp the neck. If you do, just remember that your are increasing chamber pressure and pay strict attention if you are operating near the upper limit of that powder. (MK262 clones)

In my process, I've seen no signs of increased pressure. I did a .223 crimp/chrono test years back with a variety of crimps and no crimp and could find no significant changes in velocity.

For semi-autos, you want to full length size. Period.

I like to full length size everything every time. Bolt gun and Gas gun.

Mixed headstamps can/will give you mixed headspace lengths. Fine for hoser ammo but not precision stuff. Remember that whole consistency equals accuracy thing.

The best groups I've ever shot in .223 have been mixed brass. .308, etc is a whole different story.

Yes, you can load precision ammo on a progressive press but it take some/alot of modification and knowing what you are doing.

Simple die selection gives me great ammo on my 550b. I single stage and arbor press for bolt gun.

I can't wait until you discover case and bullet runout.

I'm try to avoid runout, but shooting tangent ogive bullets makes it less critical. I took the worst runout rounds i could find out of a box of BH 168 smks and shot the group... expecting horrible accuracy. But they shot just as good as the straightest rounds. I think the "bad" rounds were running .007-.010" runout if I remember right.

[bigedp51]

The biggest cause of neck runout is when the expander is locked down off center and induces neck runout.

Below even the cheaper Lee full length dies have a expander that is reasonably centered that does not move in the collet clamp. Meaning if you do not have a runout gauge and clean the threads on the expander spindle and clamp you will produce better than average ammo. It is the RCBS, Redding and other brands that the expander can be locked down off center



If you want to spend a little more then the Forster full length benchrest die with the high mounted floating expander will reduce runout even more.

The Forster full length die holds and centers the neck of the case in the neck of the die when the expander enters the case neck and can not pull the neck off center.

]nout.

And the Forster benchrest seating die holds the bullet in perfect alignment with the case and can not tilt and induce runout. And these dies are cheaper than redding.




Also if you lube the case neck by dipping the neck in powdered graphite it will greatly ease sizing with the expander and when seating the bullets.

[bigedp51]

I'm try to avoid runout, but shooting tangent ogive bullets makes it less critical. I took the worst runout rounds i could find out of a box of BH 168 smks and shot the group... expecting horrible accuracy. But they shot just as good as the straightest rounds. I think the "bad" rounds were running .007-.010" runout if I remember right.

A full length resized cartridge is supported in the rear by the recessed bolt face and by the bullet in the throat. Meaning the case body and neck do not touch the chamber walls and gives the bullet wiggle room to be self aligning with the axis of the bore.

The military considers match grade ammunition to have .003 or less bullet runout.

Below with a full length resized case only the case shoulder contacts the chamber as long as the case is not warped and banana shaped. If the case has unequal case wall thickness the thin side of the case will expand more causing the case to warp. And this causes the base of the case to be no longer 90 degrees to the axis of the bore and push the rear of the case off center. Meaning full length resizing with adequate head clearance minimizes case mis-alignment with the bore. "The cartridge should fit the chamber like a rat turd in a violin case"





Below Mr. Salazar is explaining the benifits of "full length resizing" when asked about partial full length resizing that does not reduce case diameter enough for chamber clearance.

Reloading: Partial Neck Sizing
by German A. Salazar
http://riflemansjournal.blogspot.com...ck-sizing.html

"Now the last scenario, a full-length sized case in which the neck is also fully sized. There is clearance at the neck and in the body of the case, the closest fit anywhere is the bullet in the throat. If the neck to bullet concentricity is good (although it needn't be perfect), then the bullet will find good alignment in the throat and the case body and neck will have minimal influence. Let's not forget that the base of the case is supported by the bolt face or the extractor to a certain degree as well; this is yet another influence on alignment. As you can see, there are several points from base to bullet that can have an effect. My procedure is to minimize the influence of those that I can control, namely the case body and neck, and let the alignment be dictated by the fit of the bullet in the throat and to some extent by the bolt's support of the base. Barring a seriously out of square case head, I don't think the bolt can have a negative effect on alignment, only a slightly positive effect from minimizing "case droop" in the chamber. Given that a resized case will usually have a maximum of 0.001" diametrical clearance at the web, this isn't much of a factor anyway."

[P2000]

Also if you lube the case neck by dipping the neck in powdered graphite it will greatly ease sizing with the expander and when seating the bullets.

As always, great info and diagrams bigedp51! I didn't know this application media existed. I've been using imperial dry neck lube, applying it to the inside of the neck using a q-tip like a moron. Ordering some now.

[bigedp51]

As always, great info and diagrams bigedp51! I didn't know this application media existed. I've been using imperial dry neck lube, applying it to the inside of the neck using a q-tip like a moron. Ordering some now.

When you wet tumble with stainless steel media it removes all the carbon from the inside of the case neck. And graphite powder is nothing more than very fine ground carbon and the expander smears and spreads this carbon inside the neck recoating it. This carbon coating also helps keep the bullet from bonding to the case neck and increasing bullet grip over time.

[markm]

I've been using imperial dry neck lube, applying it to the inside of the neck using a q-tip like a moron. Ordering some now.

I don't run any lube for neck expansion since it's on the down stroke. If I felt any sort of resistance on the press I would probably lube, but I don't thinks it's been a problem.

[P2000]

I don't run any lube for neck expansion since it's on the down stroke. If I felt any sort of resistance on the press I would probably lube, but I don't thinks it's been a problem.

I've tried with and without lube. It is much smoother feeling with lube(on my rockchucker) but I can't say if this translates into any measurable benefit downrange. It just felt better to me.

That's the catch, will any of these extra steps help anything. Once I reloaded a batch of 100 rounds and did an experiment. I used my concentricity gauge to measure all 100 rounds. I went to the range and fired the most concentric 10 on paper, vs the worst 10...both groups were very similar.



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[VinnAY]

I really strive to load good quality stuff with consistency but there's just no way on this Earth that I'd devolve the process in to what is about 99% of this thread.

[markm]

I really strive to load good quality stuff with consistency but there's just no way on this Earth that I'd devolve the process in to what is about 99% of this thread.

Yeah. You have to pick your battles. There's no limit to the insanity.... Deburing flash holes, messing with primer pockets... weight sorting brass, etc. Those are the things I refuse to even consider.

I slowly added the steps necessary as I evolved from my early years of just loading FMJ basic ammo.

The real ass ache for me.. is SS media wet tumbling. That adds a lot of time and handling of brass. But I could never go back to working with marginally clean brass.

[twadsw01]

Why is that, markm?

Also, what would y'all (markm, anyone) say is the least amount of steps/work/processing that can be gotten away with for loading just "FMJ basic ammo"?