I can't find the thread where I read this.  I was wanting to try the lube we made because I just got finished sizing about 400 once fired mil cases that took about 3 times as much imperial sizing wax as compared to my normal resizing from a bolt gun.  I know, machine gun brass is harder to resize.

I seem to remember a foam lined coffee can, 50 drops of hoppe's#9 and STP something (can't remember if transmission fluid or oil treatment) for a thin slick lube.  Applied by tumbling a bit in the coffee can.  Thought I might give it a whirl on the next 1600 pieces of brass.

I thought it was a recent post and I've pulled up every thread I thought I read and control-F searched for STP and coffee.  Can't find it though.

TIA
TD


Edit:  Changed the thread title to better reflect what this has turned into.  The original title was Who was using a foam lined coffee can on their wet tumbler to lube brass for resizing?

Update below.

2nd Edit
Put use 100% STP in the subject so you don't have to worry about something the Hoppes may or may not do.

3rd edit
Changed the post title from '60% STP oil treatment and 40% Hoppe's #9 is a viable case lube.  Edit: use 100% STP'

Seems a little crazy to use case lube that might contaminate primers or powder.

I'm pretty sure it wasn't a thread by itself, but a reply inside a thread.  Or a link inside the reply.  For the life of me, I can't figure out where/how I got to it.  I can find pages on google that have the words: stp coffee can lube thin case sizing in the page but no recent ones at ar15.com.  I may have been following links and ended up somewhere else.

Googling around I saw a 60/40 and a 50/50 mix of Hoppes #9 and STP oil treatment.  I also found an article where STP was originally used as a lube for sheet metal forming dies before they figured out to use it for an oil treatment.  Just for grins, I think I'll give it a shot.  I'll let everyone know how it goes.

It would be easier for me to get a can/bottle of STP tomorrow than trying to find lanolin.  I have the bullet lube for cheap bastards thread bookmarked, so I do know about that.

I'm not worried about clean up or contaminating anything with it.  The resized cases will go in the wet tumbler with SS pins and a lot of Dawn that should take it right off.  I've got a ton of the '1 lb, i.e. 12 oz' plastic coffee cans to use.  Losing one won't be that bad.

Lanolin in an alcohol vehicle won't hurt powder or primers.  The alcohol evaporates quickly, and lanolin is an organic wax that can't hurt powder, primers, your skin, etc.  For the record, Dillon's spray lube is essentially lanolin in alcohol.

12:1 99% alcohol to pure lanolin is the best case lube there is.

I know.

STP and Hoppes aren't made from lanolin and alcohol.  


And to the OP, many drugstores carry lanolin.

Sorry, I missed that connection.  The placement of your post made it look like you were talking about lanolin/alcohol.  My bad.

Here you are:

https://thefiringline.com/forums/showthread.php?p=5798863

@TripletDad

60% STP oil treatment and 40% Hoppe's #9 mixed up in a little bottle IS a viable case lube.

The measurements of the proportions was by Mark I Eyeball in the bottle.  Pour in some STP, then fill up the bottle a little less than twice what it was with Hoppes.  Then shake to mix.  After a couple of hours, it's not separated like oil and vinegar salad dressing. (Edit: yes, it does separate.  You'll have to shake it up before use.)

I tore up a few strips of paper towel, put them in a zip lock sandwich bag, poured in a little lube, added the cases and shook them around a bit.  I also kneaded the bag to make sure it was all over the cases.

130 machine gun fired .308 cases resized just as well with this as they did with Imperial Sizing wax.  There was a little chatter on one case, but I was getting 2 or 3 cases per 130 (what fits in my home made tumbler) doing that with the Imperial.  This STP lube required maybe a bit less force on most cases.  Hard to say for sure, but definitely not worse.

You could tell where the lube came out of the die's vent hole after I removed it from the press.  I had them over lubed on purpose.  These cases had been a bitch to resize even with Imperial.

I did not add any more lube to the baggy after the .308s.  I was just using the dregs on the side of the bag to do 450ish pieces of .357 Sig in a Lee steel (not carbide) sizing die.  As a further test of the lube, I got 50 .40 cal pieces of brass and resized them down to .357 Sig at the end.  No problems with the brass sticking or galling in the steel die.

This lube cleaned up off my hands easier than Imperial.

I wet tumbled (with pins) the .308 brass with a little lemi-shine and Ajax dishwashing liquid - too cheap for Dawn.  When I opened the tumbler, the brass did not look, smell or feel any different than brass resized with Imperial.  The sides of the PVC pipe tumbler body were NOT gunked up with anything.  I could not detect any STP or Hoppe's smell on the cases or tumbler.  I could smell the lemon scent in the soap.

You've already got the Hoppes.  All you need is a $2.47 bottle of STP oil treatment from Walmart and you probably have enough case lube for years.

I'm not saying you should switch, but if you need another option, this works.

Hoppes has ammonia in it, right? I tend to leave batches of lube/sized brass sitting around for days waiting their turn in tumbler (my bottleneck - pun intended). I would rather not have Hoppes on them no matter the amount or concentration.

Ammonium Hydroxide in #9.  

Ethyl Alcohol  will also damage brass. 

Vinegar is another.  Doesnt happen over night.   Takes a while.

No, I don't think you could use this stuff from a spray bottle.  It's like a real heavy weight motor oil.



Since it's been another 3 hours since I made my batch, it is starting to separate a bit.  Looks like the clear Hoppes is going to the bottom and the whitish STP is floating.  So you will have to shake it up before you use it.



I intend on cleaning the brass as soon as I size it, so the Hoppes shouldn't be on it more than an hour.  I'm not going to leave it on over night.  I don't think it would do anything in that amount of time, but better safe than sorry.

There are some people that use 100% STP.  Nothing in the MSDS (STP Oil Treatment MSDS) that looks like that would be a problem.  But it would be thicker than snot.  I would guess you could use just about anything to thin it that is compatible with mineral oil, I don't think there's a magic ingredient in Hoppes.  It's just what I read worked so I tried it.



For the people that are worried about primer/powder contamination, what's the scenerio?  I resize on a Lee classic press and that's all I do on it.  Priming happens on the Dillon when it's loaded.  Are you worried that there's residue in the case?  My process is dry tumble a few minutes in walnut, then lube and resize.  Wet tumble to remove lube and dry a few minutes in walnut.  (Much easier to hold cases for trimming with my fingers if there's no lube on the case.  'Doh.  I won't say how long it took me to figure that out)  Trim, deburr and another short wet then dry tumble to remove any brass chips from the trimming/deburring.  I can't see a contamination issue the way I do it.  I could see an issue if I used the Lee press to prime with where some of the lube could get into the primer holder at the bottom.

What problems does this solve over the established and homemade offerings?

I forgot to add:  No I didn't use a Q-Tip or anything to get the lube inside the neck.  I do that using Imperial and it's a pain.  I think I had enough in the bag that it 'rolled' over the mouth edge of the case, so there was enough in there to work.  Like I said, this brass was fired in a large chamber and was a bear to resize.  I lubed the absolute snot out of them.  Only got 1 dent though.  It moves through the die vent hole without a problem.

I didn't want to ruin a coffee can until I was a bit more sure that it would work.  The next step is to get a sponge, cut it into 1/2" cubes to put in the can with cases and lube, then run it on the tumbler for a little bit before sizing.  I think the corners of the sponges will lube inside the case necks enough so there won't be any pull up on the shoulder on the resizing upstroke.  The paper towels just got in the way because they stuck to the cases.

My son and I will be going shooting Thursday.  I'll take some of those fired cases and resize some with Imperial and some with STP to see if one in more consistent than the other in regards to shoulder set back.  The brass we'll be shooting was annealed before the last time it was resized and loaded, so everything ought to have the same spring back.  I'll let you know how that looks when I get a chance to resize those.

Nothing I know about.  Unless you want $2.50 lube in one trip from Walmart.  No special 99% alcohol or lanoline needed.  Just another option if you run out of what you like over a weekend.

that would make a mess of my DILLON XL650 processing.

I will stick to home-brew case lube https://www.ar15.com/forums/t_6_42/305174_Case-Lube-for-cheap-bastards.html

Once again, I'm not suggesting anyone switch to STP.  I'm curious, I'm going to try it and I'll post back my thoughts and observations.  If I run into problems, you'll know about those too.  It's not like I'm going to try and market this as 'Fire Lube' and try and sell it for $4 an ounce.  I just cannot believe that I'll have a contamination problem with my process.  Wet tumbling in detergent will remove the vast majority of the mineral oil if not all of it.  Especially since I do it twice in the process.  Petroleum jelly used to be an ingredient in naval gun powder for the big guns, so it can't be all that bad.

With that said....



I just did another 130 cases with 100% STP to completely avoid what's in Hoppes that everyone is worried about and I personally wish I had done the first 800 with it.  This was much easier sizing than with either the Imperial Wax or the 60/40 mix.  Zero chatter on any case.

I'll throw this out there too.  The once fired cases I bought I went ahead and paid a little extra to have them pre-tumbled in corn cob before I received them.  I did this strictly to save time once the cases came in.  They were clean, but have a rough texture to them.  Most, if not all of the roughness goes away after the first wet tumble.  I don't what it is.  But this texture made it hard to apply the Imperial wax.  I use a blue glove on my left hand and get a bit on the fingers and rub each case as I put it in the press.  It took more wax than usual to cover the cases for smooth sizing.  I didn't call it chatter, but there were at least a couple of cases per 130 that I'd lower the ram back down, apply more wax and then resize again.  So that's why I was looking for something different.  It was wearing out my hand rubbing in the wax on every case.  This is a breeze in a ziploc baggy.

My past lube methods were a RCBS lube pad and their lube until I switched to Imperial.  I have not tried a spray based lanolin lube, so I don't know how this compares with it.  If somebody wants to send me a little spray lube, I'll be more than happy to try it and post back what I think about it.

Another thing that interested me about STP in the one post where he said he got much better dimensional uniformity with 60/40 than anything else.  When I get fired cases from a decent chamber on Thursday, I'll set my resizing die to bump the shoulder back .003 with Imperial wax.  Then using the same setting, I'll see how the 60/40 mixture works.  I think the 100% STP is too thick by itself, but if I have enough cases, I'll try that too.

This.

I've used STP before and actually started with it. But using it in a tumbler and getting it in your cases seems like a bad idea....

Sometimes you have to look at the stakes, not just the odds.  A contaminated case could cause a squib which may in turn cause a KB.

Using accepted case lubes such as Imperial, One Shot, Dillon Lube, or home-brew lanolin & alcohol is a safe choice.  

I think everyone here appreciates the outside-the-box thinking.

Has there ever been a study on how much contamination it takes to cause a problem?  I looked around for one yesterday and couldn't find anything.  I even went so far as to watch videos of case forming manufacturing processes to see if I could see anything in the background.  I also searched for brass cup forming lube & brass drawing lube.  

In Norma's vid, they have drum of gearway lube being shown during case forming.  Since I was in manufacturing for 30 years, I know they can use a much harsher detergent than Dawn or Ajax to remove whatever from the cases.  It could also be burned off during one of several annealing steps. I also know they'll use the cheapest stuff available that does the job and has no effect on the final product - due to either cleaning it off extremely well or what's left over has no effect.  (Not entirely true, the Europeans will use stuff that's more expensive because it's 'green' even though the original version has not been shown to cause harm.)  Does anybody know what they use at what stage of the process as lube?

I looked to see if there was anything in Hatcher's notebook.  Only thing I saw there was the formula for cordite mark 1:  37 parts guncotton (nitrocellulose), 58 parts nitroglycerin and 5 parts vaseline.  5% 'contamination' is a much larger percentage than any thing left over on the case but as far as I know, cordite went bang when they wanted it to.

Once again, I understand everyone's concern.  Beware of contamination.  Don't let it drip directly into a primer cup.  But my shoulder is not what it used to be and if I can resize these damned machine gun fired cases easier with STP than Imperial, that's what I'm going to do.  And on the first sizing, it's been proved to my satifaction that 100% STP is easier.  If I can get better dimensional stability on resizing after firing from my bolt gun, that's what I'm going to do.  If I get the same stability with Imperial, I'll stay with it - like you said, just in case and there's no advantage in using STP.  I think I know the risks and I think I can manage and mitigate them.  And it's not a bad thing to point them out to everyone else.

However, if anybody does have a study, please share it with me.  I never turn down hard data when making decisions.

Forget contamination, just the mess and smell is enough to make me shake my head in wonderment.  This may have worked, but the residue left behind...and in the case necks?   Seriously, experiment away, you won't be the first.  The ISO-Lanolin lightly applied is hands down THE best lube for sizing, especially when used on a progressive.  I lay out 3-500+ cases out on a towel with all laying flat, NONE with the case mouth up.  This eliminates ball powder from sticking in the mouth.  If I need to lube case mouth before sizing, I soak a Q-tip with One Shot and this will prevent the stretching on larger rifle cases.  Finish up the Match prep with a size appropriate bore brush twisted in the case mouth.  Works well for uniform tension in conjunction with annealing.   STP...no way.

I've read lots and lots of reports of "my standard practice" involving all sorts of petrochemical lubricants, without any subsequent reports of bad outcomes.  I don't know whether or not there were bad outcomes, so maybe not, but maybe there were no reports because the user didn't report it, or couldn't report it.

With that said, I'd like to see a test of "STP as a case lube" with various levels of "neatness" in its application to see if there is any real value in its use.  The SDS for STP Oil Treatment shows it as mainly mineral oil and with a pH of slightly to very alkaline, and that it is very slippery.  But one of STP's benefits in an engine is that it helps motor oil stick to parts, so it's also pretty sticky.  How much does it take to make powder clump in a case?  That's a good darn question.

Several random points, so grab a handrail and hold on:

1.  Hoppe's #9 has ammonium oleate not ammonium hydroxide.  

2.  Ethanol in the ethanol/lanolin lube is not on the brass long enough to cause any issue.  

3.  STP is petroleum blend.  I am not sure what the current ingredients are (and the MSDS is of precious little use) but at one time in contained methyl isobutyl carbinol (MIBC) which is a pretty bad chemical to expose yourself to.  I have no issue using STP in an engine if that is your cup of tea, because engines run on gasoline which contains benzene and butadiene.  However, I do not willingly and knowingly bring petrochemicals like these into my house.  

Just my opinion.

Regards,
dcat

See SDS for #9   

I would never use any motor oil or oil treatment for a lube since I use my tumbler to remove the lube and that would contaminate it in no time. Imperial sizing wax comes of easy and doesn't contaminate the untreated corn cob media that i use.

And health food stores. 

Looks like they reformulated from when I last contacted them.  Thanks for the updated SDS.

Now here’s a dilemma, is possible contamination worth it or not?

Conclusion

STP is a better case lube than Imperial wax in regards to final case head to shoulder length.  This was true for both the 60%/40% mix of STP and Hoppes #9 and 100% STP.  There was no noticeable difference between sizing effort of Imperial wax and the 60/40 mix, but 100% STP required less effort to resize than either of the other two lubes tested.



Procedure

Brass was taken from test loads fired today that had been annealed using 750 degree Templaq prior to their last resizing and loading.  The sample consisted of 47 pieces of LC-11 LR unmarked brass and 34 pieces of PMJ-10 + NATO marked brass.  

All pieces were tumbled in dry walnut for approximately 30 minutes and then deprimed using a Lee universal depriming die.

When tumbling and depriming were complete, each piece was measured with a Hornady comparator.  The actual measurements where 3.6xx, but only the xx portion will be noted.  The two digits of the measurement was written in sharpie on the base of each case.

The RCBS competition resizing die was screwed into a Lee Classic press to the mark I usually use.  Once the die was locked down, it was not moved during the test.

Before I started and after each lube change, I unscrewed the decapping stem and ran a strip of clean paper towel from the bottom of the die, ‘screwing’ it in until I could pull the paper towel out of the top of the die.  The decapping stem and sizing button were also wiped off.

Once all the cases were measured, they were first sorted into LC-11 LR and PMJ-10 piles.  Then each headstamp was further sorted based on the comparator measurement.  The LC-11 LR had 5 pieces that measured 25, (ie 3.625”), 35 pieces that measured 24 and 7 pieces that measured 23.  The PMJ-10 had 25 pieces that measured 25 and 9 pieces that measured 24.

Once the cases were sorted above, then each pile was divided into 3 smaller piles so each lube could be tested on each sample.  Where there were few cases or the piles were not divisible by 3, preference was given to Imperial wax and 60/40 STP-Hoppes mix.

The comparator was checked for zero at the start and after each small group.

The cases were sized using Imperial first, then the 60/40 mix and finally 100% STP.  The LC-11 LR cases were sized first, then the PMJ-10 second.  Both head stamp groups were resized before the lube was changed.

Lube was applied by placing a small of amount in 1 of 3 baggies, one for each lube.  The baggie was then kneaded to distribute the lube evenly inside the bag.  After that, each group of cases were put into the bag and squished around to lube the outside case, shoulder and neck.  The cases were removed no more than 6 at a time and held in one hand while a Q-tip saturated with the lube being tested was scrubbed around the inside of the neck until there was an even coat of lube.  (IE, all the walnut dust turned dark and the inside of the neck looked wet).  New lube was put into the baggies and distributed between the LC and PMJ case groups.

The 1st end of the Q-tip was used for the LC cases, the other end was used for the PMJ cases.  This had to be done because the end was shredding.  Each lube had its own unique Q-tip.



Results

Using Imperial Wax
2 LC pieces that measured 25 resized to 20 and 21.
12 LC pieces that measured 24 resized to 1-19, 7-20 and 4-21
3 LC pieces that measured 23 resized to 2-20 and 1-21
9 PMJ pieces that measured 25 resized to 3-20, 5-21 and 1-22
3 PMJ pieces that measured 24 resized to 3-21

Using 60%/40% STP and Hoppe’s #9
2 LC pieces that measured 25 resized to 20
12 LC pieces that measured 24 resized to 20
3 LC pieces that measured 23 resized to 20
9 pieces of PMJ that measured 25 resized to 21
3 pieces of PMJ that measured 24 resized to 21

Using 100% STP
1 LC piece that measured 25 resized to 20
11 LC pieces that measured 24 resized to 20
1 LC piece that measured 23 resized to 20
7 PMJ pieces that measured 25 resized to 20
3 PMJ pieces that measured 24 resized to 20

Summary
Imperial sizing wax had a +-.001 spread in each head stamp.  Across both headstamps, they measured 19 to 22.

The 60/40 mix was 0 spread inside each head stamp and with a .001” across both head stamps (20 and 21)

The 100% STP was 0 spread inside each head stamp and 0 spread across both head stamps.  Every case measured 20 after sizing.




Further notes and tests (yes, I know this proves nothing, but interesting none the less)

I got 10 cases of the once fired in a machine gun WCC-10 brass and measured them.  They measured between 32 and 38.  After resizing with 100% STP, they sized to 3-20, and 7-21.  No other lube was tested since I’ve already decided I was using 100% STP due to the ease of the sizing effort compared to Imperial or 60/40.  These cases had not been annealed after purchase.

I put 5 of the 40 cal cases I resized with 60/40 to 357 sig a few nights ago on the top shelf in the garage where I do my brass washing.  There has been no discoloration of the brass so far.

I loaded 5 cases of the un-annealed WCC-10 brass Tuesday night with my fingers and press covered in 100% STP on the Lee press.  These cases had been sized the day before in 100% STP and cleaned once after sizing and once after all processing was done.  I picked up each case at least 2 times.  Once to run it up into an M-Die and then prime on the Lee press on the down stroke.  Each primer was picked up with my fingers and placed in Lee’s press priming system on the press.  The next time was to hold it while using a powder funnel to charge the case.  Then a bullet was picked up with my fingers and seated on the case in the Lee press.  All 5 cartridges fired and there was no unusual velocity variation on my Magnetospeed.

I regularly pour about an ounce of mineral spirts into my dry tumbler filled with walnut to tumble the lube off lead bullet loaded 9mm.  The next few loads of brass that are dried in the tumbler after wet tumbling with pins are a bit shiny with mineral spirts and wax.  The walnut in this tumbler has not been changed in at least 18 months and is used in all my dry tumbling steps.  I’m thinking it’s closer to 3 years now.  My wife and I go through about a 1,000 rounds of 9mm a month shooting IDPA and USPSA.  All these cases are wet tumbled with the primer in and then dried for 30 minutes in the walnut tumbler.  I have not had one misfire due to contamination in years – even with re-using the walnut for everything.  The one contamination incident I have had was wet ammo after being rained on at a match.  I have not had a primer come apart after wet tumbling with it in.  I understand that mineral spirts and mineral oil are not the same, but this is one of the reasons I’m not stressing about contamination.

Now, will somebody volunteer to do the spray lanolin with the same proceedure and post the results?  I would, but don't have any and don't see the need to buy the stuff to make it.

In God I trust.  All others bring data.

Dawn dish detergent contains as much as 5% Ethanol. Link

The head to datum length may be changed by the firing pin strike, as much as .006"  in a Savage  223 bolt gun. 

After 6 days sitting in the garage, the 40cal resized to 357 sig have not discolored in any way.  Still fairly slippery.

I finished resizing the remaining 1K of machine gun fired brass with 100% STP.  It was much easier to resize and I didn't get any chatter or squeeks on any of it.  My wet tumbler still looks fine, but I've been doing loads of just resized brass with lube mixed with after processing (reaming, PP & FH uniforming, trimming, deburring) brass with no lube on it.

For grins, I took 10 7mm-08 cases from the scrap bin, lubed them with 100% STP and resized them back up to .308.  No problem doing that.  I've put 5 of those cases in the garage beside the 357 sigs and 5 on my shelf in my reloading room.  None were cleaned afterward.  If I detect any changes to the brass, I'll let you know.

Not surprised the STP works very well. For an example of just how well SYNTHETIC motor oil works as a case lube, skip to 4:23 of the video linked below:

https://www.youtube.com/watch?v=THOL_S7Hngs

Only 1 in ~10 223 cases need lube applied. I've used this approach myself with similar success.

My method: pour a few drops of oil into the oil bottle's cap, dip the case neck squarely into the ~1/8" deep oil pool, smear the oil down the side of the case, re-size. The next 6-10 need no additional lube at all, and the shoulders don't get pulled back up as the the expander ball is removed. Tumble 30 minutes to remove the lube. Lots of time saved and you can't shoot enough to use a quart of oil.

Lots of people THINK synthetic oil WILL contaminate powder, but a thousand rounds showed no visible evidence of contamination for me.

Why did I stop using it? No one with credibility could guarantee the oil would not contaminate smokeless powder. Despite the extraordinary ease and time savings, I personally felt it wasn't worth the "risk" especially for precision ammo.

seriously.....

OP, you really should try the home brew lanolin

https://www.amazon.com/dp/B0014AWF0S?tag=vglnk-c102-20

when you bring it up at amazon, they encourage you to bundle it with alcohol

...it's THAT popular

https://www.ar15.com/forums/t_6_42/305174_Case-Lube-for-cheap-bastards.html

typically, around here, if everyone suggests something,....there's a 99.9% chance it's a good idea

I have (finally) finished all the processing on the cases.  All 1K of the machine gun fired brass that was sized with 100% STP (60/40 also) passed the Lyman case gauge.  I hate to admit it, but that's the first time I've NOT pulled a neck up on any case that caused a gauge issue on mil once fired brass.

All the brass I have in my reloading room and the ones still in STP/Hoppes in the garage still look fine.



It's not like I'm saying everyone should switch to this.  All I'm saying is that if you run out of lube and you have to get something sized, you can do it easily with STP.  I still think as long as you clean the brass well afterwards, there won't be a contamination problem.  I have not tried the home made lanolin lube, but compared to an RCBS lube pad and Imperial sizing wax, STP provides easier and more uniform case sizing.


I may try homemade lanolin in the future, but that would require ordering stuff because you can't pick up what's needed at Walmart.  It still wouldn't be a great comparison because all the MG fired brass has been processed and resizing brass that's been fired in my guns was never an issue with Imperial.  It was the MG brass wearing my shoulder out with what I was doing that prompted me to try this.

Even if you can't pick up everything at Walmart for the home brew lanolin, you can at your local drug store.

You seem intent on convincing yourself by convincing us to use your lube.

Reinvent the wheel all you want and use what you want for lube, but most folks aren't gonna use something that can potentially kill primers or powder for their lube.

I would worry about long-term microstructure damage to the brass from the Hoppes.  It sounds like a recipe for premature cracking/degradation of the brass over the long haul.

It's got ammonia in it; it's less than ideal considering the vast number of commercial formulas and DIY recipes out there that don't contain detrimental materials.

As I continue to use this, I'm using 100% STP, not the 60/40 mix.  I tried the mix first because that was the original article I read.  However, I'm having good results with the straight stuff.  The cases resize sooooo much easier than the 60/40 mix or Imperial wax..  I just did another few hundred 308s and 223s today and my shoulder feels fine.  

I had the same concerns with the Hoppes.

So far, other than the test pieces I have laying around, I've not left any of the STP lube on any case overnight.  (BTW, still no visible change on any of those.)

How do you plan to clean your STP-lubed brass?  Dawn does a bang-up job on all sorts of oil-like stuff, so I'd expect that a basic wet tumbling mixture with Lemishine and Dawn, with or without stainless media, would take care of it just fine, especially if the brass was already wet tumbled with media before sizing.

From your posts, I'm seeing a real purpose in using something like STP.  With extremely hard to size cases, it seems to give you better, more consistent sizing with less effort.  That's worth something.  Since this sort of brass is usually "machine gun brass," it could be helpful to process this stuff with STP lubrication, and then handle it with more conventional lubrication after firing in your own rifle.

As a first reloading approach for machine gun-fired brass, I can see merit in this.  It looks like that first processing would require double cleaning the brass - before STP sizing and then again afterward - which would be cumbersome.  But if it makes it that much easier to use bulk surplus brass, I think it's worth trying.  Especially since I have about 1300 LC 7.62 cases waiting for me to process...

My new process - at least while I'm using STP - is as follows:

When you open the STP, DON'T remove the seal on the top.  Just punch through it with a small allen wrench to make a hole.  It's easier to squeeze STP out like tooth paste than to pour.


As long as the brass is not muddy & grimy nasty, I tumble for 15 minutes or so in walnut to get the grit off the cases so I don't scratch my dies.  With the machine gun fired WCC & PMJ cases I purchased, I bought those pre-tumbled in corn cob so I didn't have to screw around with them when they arrived.  If it's muddy and grimy, I wet tumble with pins (primers still in) for 30 minutes or so.  All I'm trying to do here is have cases that aren't gritty going through the dies.

Dry for 15 minutes in walnut.  I just don't want water in my dies.  I did not do this for the purchased brass since it was already dry.

Put a dallop of STP about the size of large rifle primer on the inside of a ziploc sandwich baggy and rub it around the inside of the bag by closing it up and wadding and unwadding the sandwich bag.  Use about twice that much to start until you get a feel for how it's going to work and then you can lean the amount out.  Even with 4 times that amount, I was not getting dents in the case shoulder.

Fill the bag up about halfway with brass, close the bag leaving lots of room for the brass to move around and knead and shake it for 15 to 20 seconds.  That'll be 30 to 40 or so 762x51 or around a 100 556x45.  I was doing 2 half bags of brass before adding another smear of STP.  I did not do anything special for the case mouths.  After I got finished with all the cases and took the die apart to clean it, there was plenty of lube on the expanding button and stem.

Wet tumble with pins, lemishine and the detergent of your choice for as long as you normally do (I go about 2 hours because I like them really shiny).  

Dry however you normally do.  I use 15 minutes back in the walnut.

Ream, PP uniform, flash hole deburr, trim, inside and outside deburr.  I only did the PP uniform and flash hole deburr because I was making ersatz match brass and weighing to produce my 'lots' of brass.

Because I was doing all the uniforming and trimming the brass over 20 thou, I decided to do another 30 minute wet tumble with pins and another walnut drying cycle to remove all the brass chips.  I also thought that might be a good thing to do because of the STP.  You may or may not decide to to do that.  However I was doing this using Imperial wax when I started, so it wasn't an added step for me.  I wanted to make sure the brass chips were gone and it's a bonus clean.

Case gauge and do a paper clip check for head separation.  All the cases gauged fine, I did toss a few for the ridge on the inside, but I'm sure that was the original firing, not anything to do with resizing.



I did range pickup 556 for the first time today with the above process - so no MG fired brass - I assume.  About the only effort I could feel was getting the primer out of the crimp.  Other than that, sizing was effortless - which my shoulder greatly appreciates.  It was also much faster than Imperial because I was not individually rubbing wax on each case and using a brush to get some lube on the inside of some of  the case necks so they wouldn't get pulled back up.  At first I was case gauging everything because I couldn't feel the resizing with the exception of a couple of PMC cases.  Somebody around here has a sick AR.  But even though you don't feel the sizing, the cases are being sized.

Which specific STP Oil Treatment are you using?  Plain-jane blue bottle?  Synthetic Oil Treatment?  High Mileage Oil Treatment?  Just curious.

Plain jane blue bottle I got off the shelf at Walmart in the automotive dept.  Red STP logo, oil treatment in a blue bar, 'helps protect against engine wear' in a yellow bar right below the blue bar.  15 Oz.  Has a small 201093W in the front upper right corner, but 201094W on the back label.  The barcode# is 0 71153 65148 7 on the back.

If you do decide to try this, please post back what your thoughts are in regards to re-sizing effort and what you are comparing it to.  If you could take time to take some case measurements too, that would be wonderful.

Do your machine guns need exactly perfect brass or something?

Sounds like a big factor for him is resizing force and STP is reducing the force necessary compared to other methods he's used.

Arthritis can be a bitch sometimes.  

No, I don't own a machine gun.  I'm just resizing purchased once fired mil brass for my bolt gun.

Ain't that the truth.

An interesting observation today.  I resized 130 or so 223 cases earlier this week.  My son had gotten a new upper and the the FC brass he shot in it had a reamer mark up towards the shoulder.  9 of the ~130 were random range pick ups, the others were factory FC 223 Rem brass.  I posted for help with that when I first saw it in the gun smithing forum.  I resized all those cases using 100% STP - this was the first time I'd really used it on 223.  Absolutely easy resizing.  Wet tumbled the cases in pins, dawn and lemishine, rinsed as usual and put them all to the side when I saw the reamer mark and didn't know what it was.

Anyway, just trimmed all 130 of the cases with a WFT2 timmer set to 1.752".  Exactly 6 of them touched the cutter and were actually trimmed.  Only 3 of the cases hit the cutter all around the mouth.  2 of those cases were the range pickups, 1 of the cases was FC.  The other 3 FC cases that touched the cutter only trimmed less than half the case mouth.

The reason I find that interesting is because with Imperial wax, it usually hits 60% to 75% of the cases.  I normally just toss everything in the box next to the drill press for the next deburring steps.  When none of the first 10 cases were trimmed, I stopped, got out the calipers and measured.  All the cases were below my trim length.  Grabbed more cases and kept 'trimming' until I got a case that actually trimmed.  I manually inside and outside deburred it, measured it and sure enough it was 1.752"

I'm not sure the obvious conclusion is I got less case stretching during resizing is correct because it was a new upper that had not been shot before so I had no older cases to compare it to.  Plus the reamer mark might have grabbed the case enough to keep it from growing while firing.  I can say that ammo box of factory FC has required plenty of trimming in the past.  I'll post again when we fire some of that ammo in the rifles we normally shoot.

I just put this out there and I'm still puzzling over it.  So your thoughts are appreciated on the lack of case growth.  (Except for the you're gonna die for using STP.)  I also wanted to edit the post title per Dryflash3's recommendation.



And as an aside since I'm making a post on this, the cases that have remained covered in STP for 22 days as of now have not visibly changed.  No tarnish or color changes that I can detect with my eye.  The only changes I can detect are they are not as slick because the STP is drying.  The cases done with the 60/40 mix are drier than the 100% STP cases.  None of them smell like STP any more.