Alpha Dasher brass case lip "oversized"?

[Senor_Barney]

I've come across a frustratingly large number of fired Alpha Dasher cases that will no longer chamber (easily) in the rifle from which they were fired.

For the cases that dont chamber (easily), I've found that the lip of the case neck will measure 0.273-0.2735 with a seated round...and my chamber is 0.274. As a result, chambering and extracting is not possible without a rubber mallet.

I've also found that when I neck size down in my 0.267 bushing, the lips and the body of the case neck (for the most part) measure out to ~0.267 +/- 0.0005. But, it's only when I go to the expander mandrel from PMA Tool that the lips get way over sized to 0.270 while the body remains 0.267

Reloading process:

- Wet tumble w/SS pins
- Anneal with AMP induction
- Bump/Neck size w/ 0.267 bushing
- Mandrel with PMA Tool 6mm expander mandrel (which im told is 0.242 for a final inside diameter of 0.241 after spring back)
- Wet tumble again to wash off lube
* note, this is 1-2x fired and dont require trim based on my measurments

So...my questions are as follows:

1) How to I remove the material from the lips of the case neck so that the entire neck is 0.267? Ive tried using the Lyment case prep express to chamfer the outsides...but it won't remove enough.

2) Is there a step in my process where I was supposed to address this?

3) Has anyone else encountered this with Alpha or other brass? I've also seen this relationship exists with virgin Alpha Dasher brass whereby there will be a ring around the lips that can measure 2-2.5 thou wider than the case neck body. See pics below.

4) What could cause the mandrel to create this fishmouthing of the case lips?

 

[TheOfficeT-Rex]

That flare is from your wet tumble.

Trim/chamfer/debur after your final tumble and before you prime and load. I use a skim cut every firing just for a new chamfer and debur, not to take a lot of material off.

 

[NiteQwill]

Don't tumble after you've already processed the brass. This will likely solve your issue.

Then just light trim/chamfer right before priming.

 

[mmlook]

1. dry tumble 20-30min to get the lube off
- don’t wet tumble to remove lube
- what will happen is your tumbler and pins will get coated in lube, and you’ll have to deep clean them

2. trim and chamfer

 

[Senor_Barney]

That flare is from your wet tumble.

Trim/chamfer/debur after your final tumble and before you prime and load. I use a skim cut every firing just for a new chamfer and debur, not to take a lot of material off.

Out of curiosity, what is it about the process of what tumbling annealed brass that causes this flare (good description btw). Because...whether I wet tumble dirty or wet tumble sized brass....wouldnt it cause it either way...if wet tumbling was the reason? Is it something about wet tumbling annealed brass?

To get rid of the flare, I've thought to trim. But I would need to trim back about 8-10 thou to remove the part of this neck with the flare. But the case length would be 1.835ish range vs the trim-to length for dasher at 1.855 and virgin Alpha dasher brass of 1.840

Any advice?

 

[NiteQwill]

Out of curiosity, what is it about the process of what tumbling annealed brass that causes this flare (good description btw).

To get rid of the flare, I've thought to trim. But I would need to trim back about 8-10 thou to remove the part of this neck with the flare. But the case length would be 1.835ish range vs the trim-to length for dasher at 1.855 and virgin Alpha dasher brass of 1.840

Any advice?

Tumbling in pins causes peening. No need to tumble after sizing/mandrel.

Think of it... You're literally pounding brass and stainless steel together in a tumbler...

 

[TheOfficeT-Rex]

Tumbling in pins causes peening. No need to tumble after sizing/mandrel.

Think of it... You're literally pounding brass and stainless steel together in a tumbler...

^

Any advice?

Go grab your debur tool and give it a couple spins and check it in a chamber. It'll either work, or you can come back and tell us we're wrong.

Also, maybe don't tumble so long, or try not using media on the second tumble. I tumble brass only and chuck in a couple calibers at the same time. Bitch to sort, but little to no peening. I also use a henderson, so a skim cut trim on 200 pieces of brass doesn't take very much time or effort.

 

[Huskydriver]

Wet tumble without the pins....

 

[Senor_Barney]

^ View attachment 7967734



Go grab your debur tool and give it a couple spins and check it in a chamber. It'll either work, or you can come back and tell us we're wrong.

Also, maybe don't tumble so long, or try not using media on the second tumble. I tumble brass only and chuck in a couple calibers at the same time. Bitch to sort, but little to no peening. I also use a henderson, so a skim cut trim on 200 pieces of brass doesn't take very much time or effort.

Eff...

Well, only solution is to trim back 8-10 thousandths and now have necks that are much shorter. I'll try wet tumbling cartridges alone from now on.

Will go browse the PX for new Alpha Dasher brass...

 

[Huskydriver]

Eff...

Well, only solution is to trim back 8-10 thousandths and now have necks that are much shorter. I'll try wet tumbling cartridges alone from now on.

Will go browse the PX for new Alpha Dasher brass...

The necks are fine.....resize them and you will see

 

[TheOfficeT-Rex]

I'm with huskydriver. Trim, load, and shoot. It'll buff in a firing or two.

 

[Senor_Barney]

The necks are fine.....resize them and you will see

Thanks.

I can confirm that resizing does get the necks (lips and body) down to 267...and it seems to remove the flares from peening.

However, running though my 241 expander mandrel seems to undo it all. The flared lips come back if I mandrel. No mandrel, no flare.

 

[Huskydriver]

Thanks.

I can confirm that resizing does get the necks (lips and body) down to 267...and it seems to remove the flares from peening.

However, running though my 241 expander mandrel seems to undo it all. The flared lips come back if I mandrel. No mandrel, no flare.

Post a pic of your mandrel

 

[Senor_Barney]

Post a pic of your mandrel

 

[Huskydriver]

View attachment 7967786

If I had to guess.... You are literally bottoming out the brass into the top of mandrel.

Try backing your mandrel die out 5-10 turns and recheck to see if your lip is still expanding out as far

 

[918v]

Wet tumble without the pins....

So the peening gets worse?

 

[Huskydriver]

So the peening gets worse?

I don't notice any....

 

[918v]

When you anneal the neck becomes very soft. It is susceptible to peening. Then you have your bushing die which exasperates the case mouth “flare.”

You can cut off the peened neck material with a neck turning tool.

 

[straightshooter1]

Thanks.

I can confirm that resizing does get the necks (lips and body) down to 267...and it seems to remove the flares from peening.

However, running though my 241 expander mandrel seems to undo it all. The flared lips come back if I mandrel. No mandrel, no flare.

lol . . . that makes sense that sizing would move the flare to the inside (particularly when an expander button is not being used), then it's moved back to the outside with the expander mandrel. You're only going to get rid of that flare by trimming it and I'm pretty sure you don't need to trim as much off as you suggested you would. If the trimming itself doesn't get rid of that peened flare, chamfering and deburring should do it. I ALWAYS trim my brass as the last step in my process, and when I wet tumble that takes care of thing quite well.

Note: The steel pins are NOT what causes the peening, it's the cases themselves banging against each other that does the peening. And the longer period of time used for tumbling, the worse the peening. A shorter wet tumbling period will produce less peening.

In fact, if you haven't already tried a very short period (like 15-20 minutes), the exterior of your cases will look pretty good with not much peening and though even with with the steel pins the interior will not get as clean as for longer tumbling times, but that's ok, as it's actually good to not have the carbon coating on the interior of the necks removed. Long wet tumbling times are needed for really, really dirty brass, but not for relatively light cleaning.

Often to shine up my brass, all I do is soak the brass in a bucket of hot water with some Lemi Shine for about 5-7 minutes (agitate with my hand a little); pour out the Lemi Shine water and wash with Dawn to get the acid of the brass, rinse and dry. No tumbling required. Then, sometimes all I need to do is simply use a couple twists of some steel wool to clean any remaining oxidation coating left by the annealing process. After sizing, I dry tumble with white medium size rice to clean off the lube that leaves a fine (very fine) layer of lube on the surface of the carbon coated neck interior that serves for good seating consistency. As usual, my last stem is to trim, which I do with a 3-way trimmer where is step goes rather fast.

 

[Huskydriver]

lol . . . that makes sense that sizing would move the flare to the inside (particularly when an expander button is not being used), then it's moved back to the outside with the expander mandrel. You're only going to get rid of that flare by trimming it and I'm pretty sure you don't need to trim as much off as you suggested you would. If the trimming itself doesn't get rid of that peened flare, chamfering and deburring should do it. I ALWAYS trim my brass as the last step in my process, and when I wet tumble that takes care of thing quite well.

Note: The steel pins are NOT what causes the peening, it's the cases themselves banging against each other that does the peening. And the longer period of time used for tumbling, the worse the peening. A shorter wet tumbling period will produce less peening.

In fact, if you haven't already tried a very short period (like 15-20 minutes), the exterior of your cases will look pretty good with not much peening and though even with with the steel pins the interior will not get as clean as for longer tumbling times, but that's ok, as it's actually good to not have the carbon coating on the interior of the necks removed. Long wet tumbling times are needed for really, really dirty brass, but not for relatively light cleaning.

Often to shine up my brass, all I do is soak the brass in a bucket of hot water with some Lemi Shine for about 5-7 minutes (agitate with my hand a little); pour out the Lemi Shine water and wash with Dawn to get the acid of the brass, rinse and dry. No tumbling required. Then, sometimes all I need to do is simply use a couple twists of some steel wool to clean any remaining oxidation coating left by the annealing process. After sizing, I dry tumble with white medium size rice to clean off the lube that leaves a fine (very fine) layer of lube on the surface of the carbon coated neck interior that serves for good seating consistency. As usual, my last stem is to trim, which I do with a 3-way trimmer where is step goes rather fast.

Maybe that's why I haven't seen it I don't wet tumble very long usually under an hour

 

[Senor_Barney]

lol . . . that makes sense that sizing would move the flare to the inside (particularly when an expander button is not being used), then it's moved back to the outside with the expander mandrel. You're only going to get rid of that flare by trimming it and I'm pretty sure you don't need to trim as much off as you suggested you would. If the trimming itself doesn't get rid of that peened flare, chamfering and deburring should do it. I ALWAYS trim my brass as the last step in my process, and when I wet tumble that takes care of thing quite well.

Note: The steel pins are NOT what causes the peening, it's the cases themselves banging against each other that does the peening. And the longer period of time used for tumbling, the worse the peening. A shorter wet tumbling period will produce less peening.

In fact, if you haven't already tried a very short period (like 15-20 minutes), the exterior of your cases will look pretty good with not much peening and though even with with the steel pins the interior will not get as clean as for longer tumbling times, but that's ok, as it's actually good to not have the carbon coating on the interior of the necks removed. Long wet tumbling times are needed for really, really dirty brass, but not for relatively light cleaning.

Often to shine up my brass, all I do is soak the brass in a bucket of hot water with some Lemi Shine for about 5-7 minutes (agitate with my hand a little); pour out the Lemi Shine water and wash with Dawn to get the acid of the brass, rinse and dry. No tumbling required. Then, sometimes all I need to do is simply use a couple twists of some steel wool to clean any remaining oxidation coating left by the annealing process. After sizing, I dry tumble with white medium size rice to clean off the lube that leaves a fine (very fine) layer of lube on the surface of the carbon coated neck interior that serves for good seating consistency. As usual, my last stem is to trim, which I do with a 3-way trimmer where is step goes rather fast.

Messed around all Saturday afternoon. Here's my final conclusion.

Peening, as I understand, is essential metal banging against metal. Like a blacksmith forging and shaping metal. However, with 100+ pieces of Dasher brass in a FA wet tumbler, one wouldnt expect the case flare to be concentric as I am eperiencing. In other words, the peening would result in mircro dents / dings / whatevers randomly all over the lips. But what I have is the result of "something" that is impacting a case lip flare the same all the way around.

So what is that something...?

I think it is the mandrel since it is the only thing that touches the entire 360 degrees of the case mouth. And this makes sense given the flares only occur post mandrel. But why?

My guess would be one of two things:

1) Material building up at the case lips that is forcing the lips to expand.more than the body. Is this material brass...carbon...im not sure.

2) Overstretching the lips. The analogy here is when you over stretch the elastic on the neck of a t-shirt it becomes loose and shapeless. I think this might be happening on a micro level where the expander mandrel forces the necks to expend too much / too quickly...resulting in a flare. Is this is the case...im at a loss how to resolve that.

I trimmed the brass pieces. 1.840 wouldnt do it. I needed to go to 1.834-1.836 to completely remove the flared portion of the necks.

Fingers crossed I have enough neck left...

 

[Cascade Hemi]

Peening also work hardens your brass.

Just chamfer the case mouths and stop wet tumbling your brass in the future.

 

[straightshooter1]

Messed around all Saturday afternoon. Here's my final conclusion.

Peening, as I understand, is essential metal banging against metal. Like a blacksmith forging and shaping metal. However, with 100+ pieces of Dasher brass in a FA wet tumbler, one wouldnt expect the case flare to be concentric as I am eperiencing. In other words, the peening would result in mircro dents / dings / whatevers randomly all over the lips. But what I have is the result of "something" that is impacting a case lip flare the same all the way around.

So what is that something...?

I think it is the mandrel since it is the only thing that touches the entire 360 degrees of the case mouth. And this makes sense given the flares only occur post mandrel. But why?

My guess would be one of two things:

1) Material building up at the case lips that is forcing the lips to expand.more than the body. Is this material brass...carbon...im not sure.

2) Overstretching the lips. The analogy here is when you over stretch the elastic on the neck of a t-shirt it becomes loose and shapeless. I think this might be happening on a micro level where the expander mandrel forces the necks to expend too much / too quickly...resulting in a flare. Is this is the case...im at a loss how to resolve that.

I trimmed the brass pieces. 1.840 wouldnt do it. I needed to go to 1.834-1.836 to completely remove the flared portion of the necks.

Fingers crossed I have enough neck left...

You might be onto something with your guess #1. One thing I've seen (using a bore scope for a close look) is the peening curls the edge of the mouths inwards. When a mandrel is run through, it could curl it more and causing the expansion you describe. However, that curl material would have to go beyond the existing chamfer. Also, if a chamfer tool is not making clean cuts, it can produce a burr on the inside of the neck at the bottom of the chamfer, which might also lead to the effect you're describing.

As for your guess #2, that doesn't seem plausible to me given any such working of the brass will harden it rather than make it loose.

. . . anyway, just some of my thoughts along that line.

 

[straightshooter1]

Peening also work hardens your brass.

Just chamfer the case mouths and stop wet tumbling your brass in the future.

Any work hardening done from tumbling the brass is inconsequential and at most, the hardening is only at a micron of the brass surface.

 

[918v]

Material building up at the case lips that is forcing the lips to expand.more than the body.

If you can imagine the cross section of a peened case mouth it looks like a mushroom. If you run a mandrel through that neck without first chamfering it will force all the peened material to the outside.

 

[Mike Casselton]

If I had to guess.... You are literally bottoming out the brass into the top of mandrel.

Try backing your mandrel die out 5-10 turns and recheck to see if your lip is still expanding out as far

That was my thought before even finishing your OP.
Lots of people run the mandrel in too deep.
You only need to go the depth of the neck length.

Saying that resizing removes it and the mandrel brings it back confirms that you're bottoming the mandrel against the case mouth.

 

[Senor_Barney]

That was my thought before even finishing your OP.
Lots of people run the mandrel in too deep.
You only need to go the depth of the neck length.

Saying that resizing removes it and the mandrel brings it back confirms that you're bottoming the mandrel against the case mouth.

Def not bottoming out.

That would collapse the shoulder completely. I only know this because I tried it to see what would happen.

It's super odd because I'vebeen able to replicate the flaring even when it's literally kissing the case mouth....i mean just touching it...Maybe not even 1/16 inch...

 

[Mike Casselton]

That's a little beyond bottoming out, but I see your point.

What happens if you size a case and then seat a bullet without using the mandrel at all?

Lastly, what is the loaded neck diameter measured at the middle of the neck? And to go with that, measure the neck thickness at the case mouth.

Compare the loaded diameter minus the bullet diameter, then divide by 2.

Does that number match the case mouth thickness?

Yes? It's procedural.
No? The case mouth is just thicker and can be fixed with a skim cut using a neck turning setup.

 

[CK1.0]

As already stated, you're getting the thickened "lip" at the case mouth due to wet tumbling. I've run into this.

I've tried everything known (and many things not so known) and after much trial and error have finally concluded that: I just don't think wet tumbling and precision rifle cases belong together.

That said, there is a way you can semi-easily fix your brass if you want, without having to shorten it or trim it (to cut the lip off): you can squash it with a Lee Collet Die.

You basically use the LCD as a "case mouth squasher"... Brass is malleable, you squish the neck/mouth against a mandrel and it goes back to how it was originally (annealing first wouldn't hurt).

For some dumb reason, Lee now makes the newer LCD's where they normally let some of the case mouths stick through the top... so unless you score an older one, you may also need a washer or two from the hardware store (ID big enough to fit around your case, OD big enough to sit on top of your shell holder in the press). Just slip the washer (or two) around the case before running it into the LCD, the washer(s) will allow the collet to engage sooner than otherwise, so it can squash the case's mouth back into happiness. That's it.

After, leave the wet-tumbling for blaster ammo.

(FWIW, I only own an LCD for using as described, I don't regularly use one as Lee intended ever lol)

 

[918v]

The people running Lee right now are pretty retarded.

 

[Captrjc]

There is a video from F Class John on the tube dealing with the same thing. Looks like maybe it’s a problem with the trimming
Click here for video

 

[Rocketvapor]

I have to deburr the OD on trimmed brass. Maybe a new cutter would help. I check each neck with my fingernail.
Each case gets touched around the edge with a fine file. Only removing the burr while holding the case and turning.

 

[338dude]

Eff...

Well, only solution is to trim back 8-10 thousandths and now have necks that are much shorter. I'll try wet tumbling cartridges alone from now on.

Will go browse the PX for new Alpha Dasher brass...

Wet tumbling for less time to avoid peening case mouth, and I polish my cases in a vibratory Tumblr with walnut media and a little white diamond metal polish the second time then I anneal size trim and load.

 

[Cascade Hemi]

Any work hardening done from tumbling the brass is inconsequential and at most, the hardening is only at a micron of the brass surface.

According to the AMP zealots, any difference in annealing or hardness is worth $87,000 in equipment to correct. Also, you pulled "micron" direct from your rectum.

 

[Cascade Hemi]

As already stated, you're getting the thickened "lip" at the case mouth due to wet tumbling. I've run into this.

I've tried everything known (and many things not so known) and after much trial and error have finally concluded that: I just don't think wet tumbling and precision rifle cases belong together.

Yeah. I only wet tumble pistol brass and milspec 223/308 anymore, and neither for more than 30 minutes. No steel pins.

 

[DellaDog]

I only started having issues with peening *after* I started amp annealing every piece *before* wet tumbling. Peterson 6.5 CM brass had 18-20 reloads with no issues, until I decided to clean my brass *after* annealing and sizing.

I don't think it's coincidental - annealing softens the brass and contributes to wet tumble peening.

 

[straightshooter1]

According to the AMP zealots, any difference in annealing or hardness is worth $87,000 in equipment to correct. Also, you pulled "micron" direct from your rectum.

My use of "micron" wasn't meant to be literal, but to convey and idea of the extent of hardening.

 

[CK1.0]

I had peening from the wet tumbling before I started hitting the AMP first, but yeah, it did get a bit worse once I started AMP’ing the brass every time right before for sure.

For 9mm or any other “blaster” ammo, I say bring on the wet tumbler and all the pins, works great for that stuff… just not for anything you’re trying to see single-digit SD’s with.

One’s chamfer/deburr routine definitely has an effect though: I only deburr the outside of case mouths on virgin brass and/or after I trim, that’s it, otherwise never.

That said, I’m pretty OCD about what I want to feel at the handle when seating bullets, so that means I chamfer the inside of the case mouths and lube the necks before seating, every single time. I actually think the inside neck chamfer is a fairly important step… YMMV.

 

[whatsupdoc]

@Senor_Barney Not sure how large your tumbler is, how much steel media you have in it and how much
water you have in there but everything affects the peening of the cases.

I would add more steel media and I would chamfer the case neck every single time I load.

For your immediate issue you simply need to remove the excess material. There are many ways to do this.

Take the case push it into the sizing die just enough to push the peen to the inside then use a VLD
chamfering tool on the inside of the neck to remove the peen after that push the mandrel into the neck.
Followed by an outside deburring.

If you have a tool to spin the case you can just use a fine file to deburr the outside edge.

Neck turning tool would work.

 

[Senor_Barney]

I'm Reviving this old thread with some updates I found and my experience with Lapua 6 Creedmoor brass.

The string of images below should be self-explanatory but I'll try and describe as best I can.

#1: The first picture is once fired unsized Lapua brass. It's been wet tumbled without steel pins for 28 minutes. As you can see there is no lip flaring at this point.

#2: the second picture is the same piece of brass partially sized on the neck. the shoulder has not been bumped at all as the ram was only partially pressed down. I am necking down from ~.275 to .270 using a Whidden gold bushing. Notice the lip is already starting to flare.

#3: the final picture is the same piece of brass but this time fully sized and the entire neck is down to .270. When comparing picture three to picture one there is a definite flaring of the lip that is even more noticeable by touching it with my fingernail.

Thoughts...impressions?

This could be coincidence and correlation does not equal cause but I feel as if this has been causing the neck flaring all along not the weather I tumble or not with stainless steel pins or whether I drive versus wet tumble at all. With all due respect that never seemed to make logical sense to me that a bunch of cases tumbling in water (versus a bunch of cases in corn cob) would have flared necks as other have suggested (i.e. this whole peening concep. Especially given the fact that the lip flaring is so concentric. It's not just a portion of the lip...its even the entire way around which suggests there must be a force applied to the entire neck at the same time (in this case the combination of bushing and or mandrel) that is too much for the neck to absorb.

Im curious if there is a right and a wrong way to insert a bushing and tightened it down inside the dye. For example if you don't back off the locking nut on the die so there is play in the bushing...does that pprevent the bushing from self centering on the neck and then the case will go in at an odd angle and cause flaring such as this?

 

[Huskydriver]

I'm Reviving this old thread with some updates I found and my experience with Lapua 6 Creedmoor brass.

The string of images below should be self-explanatory but I'll try and describe as best I can.

#1: The first picture is once fired unsized Lapua brass. It's been wet tumbled without steel pins for 28 minutes. As you can see there is no lip flaring at this point.

#2: the second picture is the same piece of brass partially sized on the neck. the shoulder has not been bumped at all as the ram was only partially pressed down. I am necking down from .273 to .270 using a Whidden gold bushing. Notice the lip is already starting to flare.

#3: the final picture is the same piece of brass but this time fully sized and the entire neck is down to .270. When comparing picture three to picture one there is a definite flaring of the lip that is even more noticeable by touching it with my fingernail.

Thoughts...impressions?

This could be coincidence and correlation does not equal cause but I feel as if this has been causing the neck flaring all along not the weather I tumble or not with stainless steel pins or whether I drive versus wet tumble at all. With all due respect that never seemed to make logical sense to me that a bunch of cases tumbling in water (versus a bunch of cases in corn cob) would have flared necks as other have suggested (i.e. this whole peening concep. Especially given the fact that the lip flaring is so concentric. It's not just a portion of the lip...its even the entire way around which suggests there must be a force applied to the entire neck at the same time (in this case the combination of bushing and or mandrel) that is too much for the neck to absorb.

Im curious if there is a right and a wrong way to insert a bushing and tightened it down inside the dye. For example if you don't back off the locking nut on the die so there is play in the bushing...does that pprevent the bushing from self centering on the neck and then the case will go in at an odd angle and cause flaring such as this?

View attachment 7999861View attachment 7999863View attachment 7999864

That looks so bad haha. To double the second pic is sizing with bushing only. No decapping pin or expander installed correct?

Then last pic is post mandrel opening?

 

[spife7980]

Are you using lube? Your necks are all scratchy like you haven’t been using enough and now have falling issues.

Yea, you can insert bushings upside down, writing goes down so that when the case lifts it up as it sizes it will not have interference from any lettering whatever the term is for metal rising up around the edges. With a clean bushing and a clean die tighten it down so it’s tight and then back it off a smidge at a time until you can just hear it click when you shake it in a quiet room, just enough that it can shift a smidge and self center. It’s it’s all gummy and lubed up it won’t rattle around but can still self center.

It sounds like you know and are doing just that already though since you asked for verification.

I find it interesting that you still don’t have any chamfer and deburred necks on your cases.

 

[CK1.0]

Dang. That looks awful.

It's not what you think, the bushing isn't causing the lip.

The brass is getting thicker at the lip of the case mouth due to multiple firings and wet tumbling (skipping the chamfer doesn't help either). Sure, wet tumbling without pins is not as rough on the case mouths as with pins, but it's still bad, and ~zillion times harder on the mouths/lips than dry tumbling. One can easily watch how hard the brass pieces crash into each other while tumbling around in the water once they get going... compare that to watching the brass pieces slowly vibrate around a bowl of walnut or whatever.

Since the brass is thicker at the lip, it's going to flare out.

A smaller bushing might help (FWIW I use a .268 or .266 for 6CM, followed by a .241 mandrel) but I think it might be time for the LCD case mouth squasher to come to the rescue (see post #29).

 

[Senor_Barney]

Are you using lube? Your necks are all scratchy like you haven’t been using enough and now have falling issues

Yuuupp...Hornady One Shot. And this was virgin brass that is being sized for the first time. I do use the Lyman Express, but dont waste time prepping the virgin brass since I was only shooting for barrel break in and to chamber-size the brass.

FWIW, here is the brass after

1) wet tumble 28min...let dry
2) lube + FL size + shoulder bump 1.5thou + neck size to .270
3) Wet tumble second time to remove One Shot lube. 20 min. No pins. Let dry
4) Expander mandrel .271 since my.loaded Lapua rounds measure .273

That looks so bad haha. To double the second pic is sizing with bushing only. No decapping pin or expander installed correct?

Then last pic is post mandrel opening?

Pic #2 is a Whidden FL die with the .270 bushing inserted correctly (V pointing down) and nut backed off 1/8 of a turn. It was decapped, but I removed the expander ball. It is bumped + neck sizing.

 

[Huskydriver]

Dang. That looks awful.

It's not what you think, the bushing isn't causing the lip.

The brass is getting thicker at the lip of the case mouth due to multiple firings and wet tumbling (skipping the chamfer doesn't help either). Sure, wet tumbling without pins is not as rough on the case mouths as with pins, but it's still bad, and ~zillion times harder on the mouths/lips than dry tumbling. One can easily watch how hard the brass pieces crash into each other while tumbling around in the water once they get going... compare that to watching the brass pieces slowly vibrate around a bowl of walnut or whatever.

Since the brass is thicker at the lip, it's going to flare out.

A smaller bushing might help (FWIW I use a .268 or .266 for 6CM, followed by a .241 mandrel) but I think it might be time for the LCD case mouth squasher to come to the rescue (see post #29).

Yea I call bullshit.....

I got a couple thousand rounds wet tumbled now on several firings of brass no pins...similar reloading process except I don't use bushing dies and never seen what the op is seeing

 

[Senor_Barney]

Dang. That looks awful.

It's not what you think, the bushing isn't causing the lip.

The brass is getting thicker at the lip of the case mouth due to multiple firings and wet tumbling (skipping the chamfer doesn't help either). Sure, wet tumbling without pins is not as rough on the case mouths as with pins, but it's still bad, and ~zillion times harder on the mouths/lips than dry tumbling. One can easily watch how hard the brass pieces crash into each other while tumbling around in the water once they get going... compare that to watching the brass pieces slowly vibrate around a bowl of walnut or whatever.

Since the brass is thicker at the lip, it's going to flare out.

A smaller bushing might help (FWIW I use a .268 or .266 for 6CM, followed by a .241 mandrel) but I think it might be time for the LCD brass squasher to come to the rescue (see post #29).

I have 268-270 bushings so Ill gove what you say a try and size to 268 then mandrel back up.

Also...I do chamfer and debur....but not at that stage yet.

This was Virgin brass...fired once. So one firing and one 20 minute session in water (not multiple firings and multiple tumbles).

The post before we're saying it's the pins that are doing this. So i dont use pins and now it's just the cases themselves running into each other. I feel like if I just ran them under a hose and stirred them in a bucket by hand it would happen.

 

[Huskydriver]

I have 268-270 bushings so Ill gove what you say a try and size to 268 then mandrel back up.

Also...I do chamfer and debur....but not at that stage yet.

This was Virgin brass...fired once. So one firing and one 20 minute session in water (not multiple firings and multiple tumbles).

The post before we're saying it's the pins that are doing this. So i dont use pins and now it's just the cases themselves running into each other. I feel like if I just ran them under a hose and stirred them in a bucket by hand it would happen.

You got a shooting buddy nearby or a non bushing sizing die handy? Be curious to see if 1 or 2 pieces come out looking normal without the bushing dies involved.

@Xcount or @Mr. F either of you ever see anything like this?

 

[CK1.0]

It looks like the same thing I've seen with wet tumbling... but yeah, 1X firing and 1 tumble cycle wouldn't do that.

I agree that you should probably try a regular old FL die instead of a bushing die and see what you get...

 

[spife7980]

For shits and giggles in the name of science flip the bushing over and see if it continues.

 

[Cascade Hemi]

For shits and giggles in the name of science flip the bushing over and see if it continues.

And another brand bushing. Bushings can be astonishingly poor quality.