Wet Tumbling / SS Pins

I’m not familiar with the Frankfort stuff but try it without the pins. If it doesn’t work get some blue dawn and lemmeshine. had doubts that it would clean as well till I tried it. Could tell the difference but didn’t have to mess with the pins and pick them out of the flash holes.
 
I don't use pins, I use Southern Shine Media with citrus dish soap and hot water only. Usually tumble for around 4 hours then rinse with cold water
 
If I want low SDs and plan on shooting past 50 yards with it, I no longer wet tumble it, period.

Dry tumbling is like giving your cases a massage, wet tumbling is like throwing them down a couple flights of stairs.
 
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If I want low SDs and plan on shooting past 50 yards with it, I no longer wet tumble it, period.

Dry tumbling is like giving your cases a massage, wet tumbling is like throwing them down a couple flights of stairs.
Interesting view - how long are / were you wet tumbling and with what media?

I've been solely wet tumbling for a few years now and have had no issues with damage, "peening", or anything else. I've looked for slight damage with a loupe several times - nothing. For "precision" brass I wet tumble for about 20 minutes without any pins or other media and it comes out perfect.
 
Interesting view - how long are / were you wet tumbling and with what media?

I've been solely wet tumbling for a few years now and have had no issues with damage, "peening", or anything else. I've looked for slight damage with a loupe several times - nothing. For "precision" brass I wet tumble for about 20 minutes without any pins or other media and it comes out perfect.
I wet tumble without media. Sometimes dish soap and Lemishine. Sometimes just soap. Run time about 20 to 30 mins. Rinse in cold water then bake in an old toaster oven at 240 for 30 minutes.

Never a problem or accuracy degradation
 
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Interesting view - how long are / were you wet tumbling and with what media?

I've been solely wet tumbling for a few years now and have had no issues with damage, "peening", or anything else. I've looked for slight damage with a loupe several times - nothing. For "precision" brass I wet tumble for about 20 minutes without any pins or other media and it comes out perfect.

I've tried a bunch of different ways: pins, no pins, long, short, fast, slow (using a variac) even tried some stuff I found in old Benchrest threads around the net, like throwing a few tennis balls in the drum (to take up unused volume and help slow down cases when flying around in the drum), and then thought I cracked the code by cutting up some unused Pelican foam I had lying around and throwing that in there to help (vastly improved and almost cured the peening for the most part).

For me, once the number of firing cycles on the cases started to get up there... chambering issues and the peened/rolled/mushroomed case mouth lips would eventually show up (with the only cure being a significant trim job, outside deburr would actually sort of make it worse or at least more apparent to the eye). I don't care about chasing speed, so I run my cases well into the teens or more (until they won't hold a primer really lol), I can't remember exactly when or how many cycles until the issues showed up, but eventually, they do. I also anneal every firing on an AMP before sizing and then tumbling, and wet tumbling is no doubt worse on freshly annealed brass.

But, that's not why I finally stopped the wet tumbling... In the end, it came down to getting low SDs. Almost magically, when I switched over to dry tumbling, my SDs shrank noticeably within a couple/few cycles (pretty much cut them in half). I also noticed that when I asked more than a few good shooters I was on squads with at matches about it, the answer was always the same: dry tumble (and I don't believe in coincidence).

I dare anyone reading this to try it... hear me now, believe me later (with the proliferation of the Garmin Xero, should be easier to see than ever).

IMO it's about how the cases are handled, and my hypothesis is: wet tumbling beats the shit out of cases (and that's bad for getting low SDs).

Now don't get me wrong, I still wet tumble the shit out of copious amounts of range pick-up 9mm! It's the right tool for that.

I bet most guys hate dry tumbling because it makes a mess and is a pain in the ass...

(worth trying, heard it first around here I think) I dry tumble in 20-40 grit blasting media (corn cob, but walnut or whatever should be the same) which is much finer than the usual dry tumbling media most of us are familiar with, and the finer grit blasting media pours out of cases like water and isn't nearly the same pain in the ass as the usual stuff, and no need to beat the crap out of the tumbled cases in a media separator (also potentially bad for SDs maybe). It still can make a mess and I don't want cancer dust floating around my house, so I tumble in the garage, on a timer, for 8 hours overnight (I know), no ill effects and brass comes out shiny as shit, haven't had an SD over a 6 (over 20 rounds) since IDK when.

Not saying y'all can wet tumble your faces off if you want to tho lol, and I haven't specifically tumbled without pins for 20mins for the life of the brass (which sounds fairly mild/sensible to me and might be the cheat code), YMMV.
 
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Same. Get rid of the pins and just use the soap and lemmeshine
I've only been reloading for four years but never heard of wet tumbling without pins. So far, I always use pins & a touch of dish-washer detergent and lots of water. I re-size & expand prior to tumbling and never have any issues with mostly 9mm, 30 carbine, 7.62x25 & 7.62x39. Always comes out well for me. This stuff isn't fine jewelry; Jerry Miculek actually uses a cement mixer.:eek: Aside from all that, what is "SD"?
 
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I've tried a bunch of different ways: pins, no pins, long, short, fast, slow (using a variac) even tried some stuff I found in old Benchrest threads around the net, like throwing a few tennis balls in the drum (to take up unused volume and help slow down cases when flying around in the drum), and then thought I cracked the code by cutting up some unused Pelican foam I had lying around and throwing that in there to help (vastly improved and almost cured the peening for the most part).

For me, once the number of firing cycles on the cases started to get up there... chambering issues and the peened/rolled/mushroomed case mouth lips would eventually show up (with the only cure being a significant trim job, outside deburr would actually sort of make it worse or at least more apparent to the eye). I don't care about chasing speed, so I run my cases well into the teens or more (until they won't hold a primer really lol), I can't remember exactly when or how many cycles until the issues showed up, but eventually, they do. I also anneal every firing on an AMP before sizing and then tumbling, and wet tumbling is no doubt worse on freshly annealed brass.

But, that's not why I finally stopped the wet tumbling... In the end, it came down to getting low SDs. Almost magically, when I switched over to dry tumbling, my SDs shrank noticeably within a couple/few cycles (pretty much cut them in half). I also noticed that when I asked more than a few good shooters I was on squads with at matches about it, the answer was always the same: dry tumble (and I don't believe in coincidence).

I dare anyone reading this to try it... hear me now, believe me later (with the proliferation of the Garmin Xero, should be easier to see than ever).

IMO it's about how the cases are handled, and my hypothesis is: wet tumbling beats the shit out of cases (and that's bad for getting low SDs).

Now don't get me wrong, I still wet tumble the shit out of copious amounts of range pick-up 9mm! It's the right tool for that.

I bet most guys hate dry tumbling because it makes a mess and is a pain in the ass...

(worth trying, heard it first around here I think) I dry tumble in 20-40 grit blasting media (corn cob, but walnut or whatever should be the same) which is much finer than the usual dry tumbling media most of us are familiar with, and the finer grit blasting media pours out of cases like water and isn't nearly the same pain in the ass as the usual stuff, and no need to beat the crap out of the tumbled cases in a media separator (also potentially bad for SDs maybe). It still can make a mess and I don't want cancer dust floating around my house, so I tumble in the garage, on a timer, for 8 hours overnight (I know), no ill effects and brass comes out shiny as shit, haven't had an SD over a 6 (over 20 rounds) since IDK when.

Not saying y'all can wet tumble your faces off if you want to tho lol, and I haven't specifically tumbled without pins for 20mins for the life of the brass (which sounds fairly mild/sensible to me and might be the cheat code), YMMV.
When I shot handgun silhouette, you were all but asked to leave if anyone looked at your brass without a welding mask on and were not instantly blinded. Seriously, it was kind of expected to have brass look “much” better with “much more” shine than new. We all got OCD about our brass being really nice. So, back in the day, before all these “new fangled methods of cleaning brass, we tumbled the shit out of it, making sure it was extra bright.

Now, being somewhat old and old fashioned, I still do. Using walnut media, I dry tumble it with a cap full of Nu Finish over night. (Except hand gun cases, the wax builds up in the bottom of the case, is impossible to remove and basically it’s a throwaway case. 9mm is the worst offender of all). Then, completely backwards, I anneal before sizing to attempt to avoid next splitting in the resizing stage. Since I don’t shoot max loads, my brass typically dies due to neck splits which annealing has gone a long way to avoiding those neck splits and getting a lot more life out of the brass. YES, I know this is backwards of the current practice, YES I KNOW everyone else anneals after resizing. YES I know I’m a crazy old man. I come by my old nick name Crazy Will honestly, so don’t rag me about my annealing. :D (And would you mind getting off your ass off my grass).

But I’m gonna try that blasting media, sounds like the ticket.
 
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When I shot handgun silhouette, you were all but asked to leave if anyone looked at your brass without a welding mask on and were not instantly blinded. Seriously, it was kind of expected to have brass look “much” better with “much more” shine than new. We all got OCD about our brass being really nice. So, back in the day, before all these “new fangled methods of cleaning brass, we tumbled the shit out of it, making sure it was extra bright.

Now, being somewhat old and old fashioned, I still do. Using walnut media, I dry tumble it with a cap full of Nu Finish over night. (Except hand gun cases, the wax builds up in the bottom of the case, is impossible to remove and basically it’s a throwaway case. 9mm is the worst offender of all). Then, completely backwards, I anneal before sizing to attempt to avoid next splitting in the resizing stage. Since I don’t shoot max loads, my brass typically dies due to neck splits which annealing has gone a long way to avoiding neck splits and getting a lot more life out of the brass. YES, I know this is backwards of the current practice, YES I KNOW everyone else anneals after resizing. YES I know I’m a crazy old man. I come by my old nick name Crazy Will honestly, so don’t rag me about my annealing. :D

But I’m gonna try that blasting media, sounds like the ticket. Oh, I do tumble brass, out in my shop, when finished, if the wind is blowing outside the shop, I stand upwind when dumping the media. When its calm, I open all the doors and have a fan blowing the dust away from me as I empty out the media.
I think most aneal then size as i do to get their brass sizing consistent, so you're not all that crazy after all. There are other benefits (like brass life) and theres some who argue that anealing doesnt make for more consistent brass too, but I think that's why most of us do it.
I personally don't worry about my brass being super shiny but there's nothing wrong with having super shiny brass. What we all are looking for is consistency, and super shiny brass typically means it's so clean that it doesn't have any carbon left inside the neck and grabs the bullet too much or in an inconsistent way, so we don't do that. Some use various techniques and materials to "lube" the inside of the neck in order to again, gain consistency in how that bullet and brass interface occurs and how consistent that action is. In that case I don't know if super clean brass matters or not because I don't use any neolube or the like usually.
 
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I think most aneal then size as i do to get their brass sizing consistent, so you're not all that crazy after all. There are other benefits (like brass life) and theres some who argue that anealing doesnt make for more consistent brass too, but I think that's why most of us do it.
I personally don't worry about my brass being super shiny but there's nothing wrong with having super shiny brass. What we all are looking for is consistency, and super shiny brass typically means it's so clean that it doesn't have any carbon left inside the neck and grabs the bullet too much or in an inconsistent way, so we don't do that. Some use various techniques and materials to "lube" the inside of the neck in order to again, gain consistency in how that bullet and brass interface occurs and how consistent that action is. In that case I don't know if super clean brass matters or not because I don't use any neolube or the like usually.
May be me, but no matter how long I tumble, the brass always has a carbon finish on the inside. I do lube the inside of the neck before sizing but re-tumble after resizing for about an hour to get rid of all the case lube.
 
I wet tumble with pins, then use a powder graphite type neck lube before bullet seating......no problem with SDs or accuracy.

I've never seen "peening" issues, but it can be my process steps......step 1 decap....step 2 wet tumble.....step 3 anneal.....then usual reloading steps.

Problems may happen for guys that go straight from wet tumble to reloading.

Ern
 
Anyone else have any experience with getting lower SD’s based on how the brass is cleaned? Any other best practices in order to avoid or at least mitigate problems?

This has me interested, I had taken a hiatus from loading ammo and am now planning to finish the basement of my new place to include a reloading section. I have zero ventilation down there so I had planned to wet tumble but had always dry tumbled in years past.
 
Anyone else have any experience with getting lower SD’s based on how the brass is cleaned? Any other best practices in order to avoid or at least mitigate problems?

This has me interested, I had taken a hiatus from loading ammo and am now planning to finish the basement of my new place to include a reloading section. I have zero ventilation down there so I had planned to wet tumble but had always dry tumbled in years past.

Best practice: put your dry tumbler(s) out in the garage.

Dry tumbling yields lower SDs, it also yields dust everywhere, and no one wants cancer-dust floating around their house lol.
 
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That's what I did at my old place, unfortunately there's no garage available now. I could store it in the back shed and tumble it outside during certain times of the year...I'll probably end up doing that at some since you planted the seed in my mind and I now need to experiment or it'll eat away at me. I'll otherwise start off wet tumbling with and without pins...that experiment to see the impact to the SD's with dry tumbling may be a low priority if I'm satisfied with the results.
 
I have a frankford arsenal wet tumbler and 5 pounds of pins but haven’t even used it yet.

I bought a 2 gallon ultrasonic cleaner off Amazon for less than $200 and a gallon jug of the shooters choice ultrasonic cleaner and have been using that with great results.

I put the cleaner in a gallon sized storage bag, shells in the bag with cleaner and then inside a second sotrage bag. I drape the tops of the storage over the side of the cleaner (which is filled with distilled water) and then clean for 30 minutes at 120 degrees. Rinse with hot water and into a 250-degree oven for 20 minutes to dry.

The shooters choice bag can be used several times before you have to change it out.
 
The cure is to buy similar guage wire to standard SS pins[ bought if off TEMU]. Using side cutters cut 2lb pins at 1 1/2 x or 2x the length of standard pins. No stuck pins. Running hotish water with Armourall car wash and citric acid. They come out super shiny if you run them for 3 hours. Have tried without pins but they make that extra difference.
 
I am happy that I have found this thread. I normally dry tumble myself (out in the garage). However, I have just picked up a slightly used Hornady wet tumbler (with pins). I have not tried it out yet, but it sounds like if you are going to wet tumble, then do not use the pins. (y)
 
I am happy that I have found this thread. I normally dry tumble myself (out in the garage). However, I have just picked up a slightly used Hornady wet tumbler (with pins). I have not tried it out yet, but it sounds like if you are going to wet tumble, then do not use the pins. (y)
Wet tumbling without the pins leaves some of the carbon layer on the inside of the case, which is a good thing as that layer makes for better seating. Try to limit the amount of time you tumble as the longer you tumble the more the case mouths get peened (not really an issue if you're trimming the cases every time). Using hotest tap water, a little Dawn and a little Lemi Shine and tumble for 1/2 hour or less can do the job. I've even got decent results with that just with the brass in a small bucket and agitating them by hand for a minute or two.
 
Wet tumbling without the pins leaves some of the carbon layer on the inside of the case, which is a good thing as that layer makes for better seating. Try to limit the amount of time you tumble as the longer you tumble the more the case mouths get peened (not really an issue if you're trimming the cases every time). Using hotest tap water, a little Dawn and a little Lemi Shine and tumble for 1/2 hour or less can do the job. I've even got decent results with that just with the brass in a small bucket and agitating them by hand for a minute or two.
Why wouldn’t you tumble with any pins?

seems like a big waste of time going to all that trouble? throwing them in a wet Tumbler.. then having to dry all those pieces of brass,,,

Why not just put them in the Tumblr with the pin media and let it run for 10 minutes and that should leave plenty of carbon in cascade necks?

I’m going to give that a try next time

OR, don’t do any of that.. wipe your cases off or gently spin the case in green abrasive kitchen sink scrubber, wipe them completely, and then go through your loading process
 
The cure is to buy similar guage wire to standard SS pins[ bought if off TEMU]. Using side cutters cut 2lb pins at 1 1/2 x or 2x the length of standard pins. No stuck pins. Running hotish water with Armourall car wash and citric acid. They come out super shiny if you run them for 3 hours. Have tried without pins but they make that extra difference.
Ha ha I was thinking the same thing when I thought my pins were all worn out ( they tend to lose that sharp edge that’s created when they’re cut crudly but whatever machine cuts them when they ship them out to us or throw them in the Tumblr kits )

but I just bought some pins on sale and it turns out my pins were still good. It was because I was overloading the Tumbler with too many brass pieces .

I stopped throwing so many pieces brass in the tumbler and they came out nice and shiny
 
Why wouldn’t you tumble with any pins?

seems like a big waste of time going to all that trouble? throwing them in a wet Tumbler.. then having to dry all those pieces of brass,,,

Why not just put them in the Tumblr with the pin media and let it run for 10 minutes and that should leave plenty of carbon in cascade necks?

I’m going to give that a try next time

OR, don’t do any of that.. wipe your cases off or gently spin the case in green abrasive kitchen sink scrubber, wipe them completely, and then go through your loading process

Well - I find it to be way LESS trouble without the pins. No worries about getting all of the pins separated from the brass and never a concern you missed any. I don't find wet tumbling to be a hassle at all.

@straightshooter1 takes the same approach I do. After tumbling for a short time I dump into a bucket and give them a good rinse and spin them in my Dillon media separator and dry in the sun or for a few minutes in the over set to about 230F - just enough to vaporize the remaining water.

The best part - ZERO dust or debris remaining!

Honestly though - do what works for you. There's definitely more than one way to clean cases. Pretty much any method isn't really going to change your results on target.
 
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Why wouldn’t you tumble with any pins?

seems like a big waste of time going to all that trouble? throwing them in a wet Tumbler.. then having to dry all those pieces of brass,,,

Why not just put them in the Tumblr with the pin media and let it run for 10 minutes and that should leave plenty of carbon in cascade necks?

I’m going to give that a try next time

OR, don’t do any of that.. wipe your cases off or gently spin the case in green abrasive kitchen sink scrubber, wipe them completely, and then go through your loading process
The only time I'll tumble with pins is when the cases have been in the dirt or mud and I want to make sure the any of that is taken care of on the inside of the cases (certainly when picking up any range brass). The wet tumbling without pins cleans up the outside of the cases very well and and even removes some of the residual burnt powder from the inside. . . no need for the hassle of removing the pins and maybe having a pin unknowingly stick and stay inside a case.

Yes . . . "or, don't do any of that". Most of the time these days, since I only do a batch of 100 or less, all I do is clean the necks with steel wool after annealing. Then after sizing, I'll dry tumble with rice, which does a great job at removing the sizing wax and reading the cases for consistent seating. Before & After:
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1724697748717.jpeg
 
I tumble with SS pins and have no issue regarding accuracy or SD.
The FA media separator does a wonderful job at separating the pins from the brass, I never had any pin in a case, and I very rarely got pins stuck in a primer pocket, which is easily seen upon priming the cases (I prime with a hand primer). I understand it could be an issue for people priming with a progressive press though.

My SD are around 2 m/s (6.5 ft/s) and I make 0,3-0.4 MOA groups on average (10 shots).

But yeah, agreeing with @Herb Stoner here, do what you please as long as you're happy with the process and the results.
 
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I gave up on using pins, except when the cases are really nasty (as in, been laying out in the mud for a few weeks). I still wet tumble, but have shortened times and only do so when the cases get really dirty. Now they just get dry tumbled and rinsed off.

That being said, with pins you will eventually peen the case necks to the point that you will start getting erratic neck tension. I'm pretty sure that is what folks are talking about, when they say that no longer wet tumble. Even without the pins, it will eventually happen.

For those of you that have been tumbling with pins, and have some old cases, you can prove it yourself. Just go and neck turn the cases (just skim cut), and you'll clearly see, at the mouth of the case, as well as the shoulder junction, and increased thickness of the brass. One from wet tumbling (case mouth) and the other from sizing cases over their life, pushing shoulder material up into the necks. I know for a fact that Hornady brass exhibits this, with cases roughly on their 10th or more reloading. These cases were trimmed and annealed at each reloading. I tried neck turning them to see if that would help. Nope. Then tried inside neck reaming. Nope. The only thing that worked was inside neck reaming, and then outside neck turning. And, to be blunt, I ain't got the time for all that.

Anyways, just tossing it out there. It's not a cardinal sin, wet tumbling cases, but you should do it sparingly. Think of it like polishing your car. You wash it all the time, but you should only polish it maybe once a year. Less is more.
 
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some good points about the tumbling with pins over along period of time and time. Of many times in a row.

I’m not sure it’s if it’s my reloading or because I aneal my cases, and I clean my Gas gun chambers after each shooting but I don’t get that nasty carbon dirty, looking cases like I see on the cases @ the range all over the place 556 brass once shot on the ground.
Brass neck/mouths must seal up a lot better than if you don’t anneal.. I don’t think it’s due to dirtier powder than what I use. I don’t think the military wants their guns failing because of poor powder burn, or dirty burning powder in general…

My bolt action guns total different story I don’t get any carbon all over the case. Only the neck has some sort of carbon on the outside, so no need to throw my brass in any sort tumbler..dry or wet ,pin or no pins…

I am considering to start using rice just polish up the somewhat grippy and rough finish that’s caused by an annealing.
 
Brass thickness changes due to tumbling? Perhaps if you are annealing =nice soft brass will definitely move around more than 10 time reload of rifle not-annealed brass.. but … I would have to look into that one and think about it for a bit?

I’m done picking up range brass …trying to shooting for precision. I have no need to try shuffle through 10 to 15 different brands of brass trying to find some sort of consistency to the point where I don’t even pick it up unless it’s a specific head stamp that I actually would use unless I’m going to load up some light loads for blasting/ training..

there’s so many different Internal capacity on these different brass..
One can go from light loads to high pressure flat primer situation if you just use the same amount of powder throughout your mass amount of reloading for range blasting..,

These are things I’ve learned from mistakes by taking 1000 rounds of range brass from all different head stamps and loading them at one grn under book max.. not a smart thing to do if you don’t know what the different 25 brands of 223/556 brass cases are going to have as far as internal capacity… I am rambling now
 
That being said, with pins you will eventually peen the case necks to the point that you will start getting erratic neck tension. I'm pretty sure that is what folks are talking about, when they say that no longer wet tumble. Even without the pins, it will eventually happen.
on 15th firing for GT brass and have yet to see this. That rig is still shoot the same, no issues. I wet tumble with pins for all brass, 30-45 min and never more than an hour.
 
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Brass thickness changes due to tumbling? Perhaps if you are annealing =nice soft brass will definitely move around more than 10 time reload of rifle not-annealed brass.. but … I would have to look into that one and think about it for a bit?

I’m done picking up range brass …trying to shooting for precision. I have no need to try shuffle through 10 to 15 different brands of brass trying to find some sort of consistency to the point where I don’t even pick it up unless it’s a specific head stamp that I actually would use unless I’m going to load up some light loads for blasting/ training..

there’s so many different Internal capacity on these different brass..
One can go from light loads to high pressure flat primer situation if you just use the same amount of powder throughout your mass amount of reloading for range blasting..,

These are things I’ve learned from mistakes by taking 1000 rounds of range brass from all different head stamps and loading them at one grn under book max.. not a smart thing to do if you don’t know what the different 25 brands of 223/556 brass cases are going to have as far as internal capacity… I am rambling now
My brass is all one headstamp and lot #. Whenever I replace a barrel, I buy 500 new cases (minimum). Old brass becomes "practice/range" brass. I figure if I get 6 loadings out each piece of brass, by then, the barrel is likely toast. Back when I competed, most matches required 300rds to have enough to check zero, and then ammo to run a two to two and half day match. So 500 pieces of brass was enough to account for that, and loss of some brass at some matches, and still have enough for the life of the barrel.

So, what I posted earlier about the peening was from the same brand/lot of brass, over the life of two rifle barrels.

And yes, the neck thickness changes as the mouths get peened. Think of it like when blacksmithing a blade or cutting tool. When you strike the flat metal with a ballpeen hammer, the metal doesn't just move out away evenly. It creates a divot, like a meteor crater, pushing material away from the point of impact, but with material flowing towards the area of least resistance (up and away at the edges). Hence, you get an uneven redistribution of material. When you hit the case mouth with pins, it is striking the material, and as it ever so slightly moves the material, the oxidation and foreign material is broken off the material. But the key here is, the material is surface hammered, causing the material to move. Granted not much, but enough to break off the oxidation. Over time, that "little" can become measurable/discernable.
 
on 15th firing for GT brass and have yet to see this. That rig is still shoot the same, no issues. I wet tumble with pins for all brass, 30-45 min and never more than an hour.
Interesting. Have you ever tried turning a case neck (skim cut) to see if neck thickness is changing? May just be the GT has more tolerance in the chamber neck(?). There's a lot of variables here, so I'm just posting what I have seen and can demonstrate.

Let me be clear. I'm not saying I'm right, or that you're wrong. Only that I have seen evidence that leads me to believe that peening does occur, and can cause problems, at least in my rifle and chambers. (6.5 CM)
 
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Interesting. Have you ever tried turning a case neck (skim cut) to see if neck thickness is changing? May just be the GT has more tolerance in the chamber neck(?). There's a lot of variables here, so I'm just posting what I have seen and can demonstrate.
I have not. This rig is coming to end of life and next barrel gets new brass. I will turn a few and see if this is happening. We run multiple cartridges and everything is processed the same and I have not seen any issues like this. That said, I mandrel, run on 3 way cutter and lube necks as last part of process before loading, so it could be process addresses this before loading.