The deeper the rabbit hole, the...

[John Weigel]

Just a couple of small observations around brass prep that recently surprised me - and may be of interest to one or two others. Firstly, after getting the idea from a youtube video from the 'Primal Rights' guy, I checked, and yes, its true that freshly annealed brass is left with a very thin, slightly gummy exude that you can feel if you rub your finger from neck, down length of case. This of course is also present on the inside of neck, with obvious relevance re seating friction, if not tension. So as suggested, I processed a small quantity of brass with my usual routine of: lube (with 'unique case lube' applied with lube-infused hand-towel), resize, clean in vibrating medium, ANNEAL, grind primer pockets, trim necks, expand neck with mandrel, prime and load. Only this tine I didn't lube necks before seating - something that I personally have until now found necessary for consistent seating tension. For comparison, I then changed the brass prep sequence to: annealing, lubing, resizing, cleaning, and so on. In the later group, presumably due to the removal of the chemical residue (?) generated by annealing, subsequent mandrel expanding was noticeably smoother and more consistent, as was bullet seating. Looks like my neck-lubing days may have passed.

Second little brainwave, and even more trivial: I've revisited my bad habit of not changing vibration cleaning medium often enough. It's a roundabout story: At Saturday's shoot at Cessnock in light drizzle, despite best efforts, my ammo got very slightly wet. More like a 'sweat' contributed by colder-than-air ammo and very humid air. I only shot one 10+2 round because of insane chamber pressure signs - super-hard bolt lift and very strong ejector impressions in case heads (and at home, detection of enlarged primer pockets and too-long spent brass to chamber easily). Then, with this incident front of mind, after prepping a batch of brass using new 'anneal first' routine, I noticed that my prepared rounds were ever so slightly greasy to the touch, perhaps more so than usual with the absence of the post-cleaning effect of annealing no longer in play. I decided to test whether or not the same lubricity issue that wet-surfaced cartridges caused at Cessnock are detectable to a lesser degree with my mildly 'lubed' cases. I shot four x four-shot groups with each of the two test groups, alternating between 'normal' (greasy) rounds, and rounds that I carefully cleaned with a metho-infused rag. No statistically valid conclusions to report, but worth mentioning, as I don't intend to test further. There was no noticeable difference in bolt lift resistance between the two groups, nor any apparent case head scarring. The metho-cleaned group generated slightly slower muzzle velocities, and slightly better groups, but no-way statistically valid. The only sure conclusion of interest I can report is that there was a nearly consistent difference between the two groups in spent case base-to-shoulder measurements: Using my gauge, all 16 cases from the 'greasy' rounds measured 1.559; most of the methods-cleaned rounds measured 1.558, with three measuring 1.559. By comparison, the wet rounds referred to at the start of this paragraph measured 1.565 and wouldn't chamber when back home without very strong closing bolt force. I guess that with lack of traction by brass in chamber walls, spring-back of expanded case is as greatly reduced.

Hope that's mildly interesting to someone - I have switched to the 'anneal first' method, probably dropped neck-lubing, and will keep a closer eye on the condition of my crushed walnut cleaning medium.

[MarkS]

Annealing after resizing is like trimming cases before resizing them.
Ask ten guys how they handload and you'll get ten answers but there are key steps in the process.
A good idea for all may to reference manufacturers like AMP and Nammo/Capstone more for product and process advice.

[Tim L]

Hi John,
I don't see where annealing occured in your first process?

I can't say I suffer the resedue issue but I stainless tumble and rinse before annealing so a different process to you.

Your wet case observations are something everyone needs to be aware of. There is a combination of bad thigs happening there. A damp case can be a dangerous beast. When fired the case gets hot and also expands compressing any water. That water vapourises (generating even more pressure and heat) and also acts as a friction free barrier between case and chamber. The only thing stopping that case moving backwards with the same energy as the bullet moving forward is the bolt.
Many people think that's what the bolt is meant to do, but as you point out, the friction between the case and the chamber wall is actually meant to take some of that load.
A good point to remember when chasing low SDs.
Clean cases and clean chamber = consistant result.

[John Weigel]

Good thoughts Tim. Are you sure you don’t have residue? I didn’t know until I did the finger dragging test described, and could experience the increased smoothness of mandrel expansion then seating.

You are correct that I forgot to list annealing in my description of brass prep routine - before changing it as discussed. Have now fixed that sentence. Thanks.

[Tim L]

Good thoughts Tim. Are you sure you don’t have residue? I didn’t know until I did the finger dragging test described, and could experience the increased smoothness of mandrel expansion then seating.

You are correct that I forgot to list annealing in my description of brass prep routine - before changing it as discussed. Have now fixed that sentence. Thanks.

If I do the finger drag immediatly after annealing there does seem to be some residue, mostly finger tip

Seriously though, I don't think I get any resedue, but I'm going to have a damned good check tomorrow.

[Tim L]

I anneal after sizing

But then I only neck size so I'm doing it all wrong anyway

[Rich4]

I don’t have any written data to support my claim but I feel that necks will be more consistent if sized after annealing, especially with my gas annealer.
As all metals move significantly more than most realise with the application of heat, also sizing is more consistent with a softened metal taking the form easier, also as mentioned cleaning the annealing residue off seems advantageous?

[Rich4]

Good thoughts Tim. Are you sure you don’t have residue? I didn’t know until I did the finger dragging test described, and could experience the increased smoothness of mandrel expansion then seating.

You are correct that I forgot to list annealing in my description of brass prep routine - before changing it as discussed. Have now fixed that sentence. Thanks.

If I do the finger drag immediatly after annealing there does seem to be some residue, mostly finger tip

Seriously though, I don't think I get any resedue, but I'm going to have a damned good check tomorrow.

Maybe just wait a few more minutes before touching the hot thing to prevent residue contamination

[BATattack]

After annealing the surface finish if brass becomes "furry" and tends to gall. Tumbling burnishes that surface smooth again resulting in smoother sizing and seating.

[Weairy]

You'll get 100 different answers and processes here.

But I generally;
Decap
Primer Pocket
Wet tumble (stainless media) and rinse
Dry in dehydrator
Anneal
Lube
Collet Die
Body Die
Small Base Body Die
Petrol wash to remove case lube
Tumble and dry
Trim
Load.

Brass comes out uniform and without any issues loading etc.

[KHGS]

My brass prep procedure, not suggesting that my way is the only way. Right from when I started annealing every loading, I chose to anneal first for no particular reason except that it seemed logical to me. I anneal, body size and decap, clean ultrasonicly, trim, primer pocket clean, inside neck brush with a very stiff nylon brush and neck size (collet die, I don’t neck turn). I have consistent neck tensions when seating bullets as measured on a force gauge on my arbor press. The logical reason for choosing to anneal before body sizing was to ensure consistent shoulder bump which is more difficult to achieve with the 40degree shoulders on my cases, annealing has rectified this issue. As an aside, I shoot only moly coated bullets. For information only.
Keith H.

[tom1]

Hi Keith, I have a question for you regarding case prep. I use a 308 Omark. I use a Redding small base die then a Lee collet die. Is the small base die overkill ? Should I use a body die instead? I have not had any extraction problems with the method I use. Hope I haven't hijacked this thread John.
Brad Probert

[KHGS]

Hi Keith, I have a question for you regarding case prep. I use a 308 Omark. I use a Redding small base die then a Lee collet die. Is the small base die overkill ? Should I use a body die instead? I have not had any extraction problems with the method I use. Hope I haven't hijacked this thread John.
Brad Probert

A small base die is very useful when you need to use brass fireformed in a larger chamber such as a “loose” factory chamber in a smaller chamber. When sizing brass for the chamber that it was fired in a std body die is a better choice as it will not overwork the brass. If you are having good brass life using your small base die I would continue what you are doing particularly in an Omark which has weak extraction and poor primary extraction.
Keith H.

[tom1]

Thanks for your advice Keith, much appreciated.
Cheers Brad.