Stainless Steel media affecting neck tension

jimmyjazz said:
I've been using RCBS sizing lube and have 4 bottles of it to go through but I'll pickup some of the imperial and see how it goes.

I tried chamfering the necks after cleaning and it's better but still get 4-5 out of 100 the shave hoping to get none or I'll go back to walnut in vibrator.
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Well that would be a step backward I'm thinking. Have you tried chamfering with a vld chamfer?
 
When I stated the excessive neck tension was caused by too much chamfering, I was referring to the wire edge of the case mouth being curled over, during SS tumbling, which can cause bullet shaving.
 
The only thing SS tumbling causes is more friction between bullet and case due to clean case mouths. When using walnut, you still have residues left in the case mouth which act like a lubricant. SS removes all of this and will FEEL like increased neck tension. As to your shaved bullets, if you haven't changed anything else in your loading procedure other than SS cleaning, I'd say your necks are getting too thick and require turning.

Peening your brass with SS pins in water with a mostly sliding action of pins against brass, I've got a lovely bridge to sell you.
 
If I can maybe state some simple thought. Are the bullet diameter what is on the box? Measure a few to confirm. Is there galling inside the case neck. Other factor I'm wondering if it is friction due to overly clean neck such as you get from ultrasonic cleaning like in this article: http://bulletin.accurateshooter.com...eaning-case-neck-friction-and-bullet-seating/

Some dry case neck lube could resolve your seating issues if it is overly clean. I run SS media as well and have not experience any additional neck tension issues. I do anneal regularly and neck turn my brass as well. I do not use any expanding button from FL die, I only use bushing dies or collet style of dies to resize the neck. I find the expanding button on RCBS die will gall the brass.
 
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I don't use SS pins yet. I am working on a tumbler for them.
However my brass gets tumbled 2x. I tumble it to clean it before I re size the case. I just use a bit of pam in a zip lock bag to lube my cases. They go through the FL die and right back into the tumbler. It doesn't take nearly as long the second time to get the lube off the cases, usually abut 30-40 minutes I find.
When I switch to SS I will de prime first, then tumble, then FL size, then tumble again to get the lube off. Then carry on from there.
 
PitBull1973 said:
I know this because I measure my loaded rounds with a digital mic with a +- half thou
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I cant confirm your experience. Though my setup may differ. My neck turned winchester brass are the same thickness .011" as measured by a mitutoyo ball micrometer before and after tumbling in a frankford for 3 hrs. I also see zero change in neck tension from my reference round I made whem I was corn cob tumbling and rounds made now w ss tumbling.

Though I also dont get shavings when seating bullets. .223 or .308, win brass, hornady match bullets. Could something be wrong with your expanding mandrel in you neck sizing die? Maybe it is seated too high?
 
Shooter ----/ said:
Peening your brass with SS pins in water with a mostly sliding action of pins against brass, I've got a lovely bridge to sell you.
Click to expand...

I'd love that bridge if it's a good deal.

Pins are too light to cause any peening, the way I figure it. it's likely sweet brass on brass action. All I figure is that it increases the thickness right at the mouth of the case enough to cause some additional headache when seating.

Took a few pieces of .270 that seem a little dinged up from tumbling (when I was learning and ran them too long). Measured the neck thickness before and after trimming, deburring, and chamfering. Seems that the peening decreases the inner diameter 0.001" or so to the case mouth.

Took a sized case and tumbled it, and tried seating a bullet and there is a noticeable (but not crazy) increase in the feel. No shaving though.

I'm still thinking it's the sizing prior to tumbling for a longer duration.

As for clean vs dirty necks? Sounds logical but I think my little experiment showed a small change in SS brass that was sized before and after SS tumbling. Overall neck thickness doesn't seem to change which also seems logical.

YMMV
 
Shooter ----/ said:
Peening your brass with SS pins in water with a mostly sliding action of pins against brass, I've got a lovely bridge to sell you.
Click to expand...



I found that with more pins, or less brass per tumble the peening stopped significantly. I added another 5 pounds of pins and have had minimal peening with 200 cases at a time.

So it's not pins peening, it's the brass on brass contact.
 
Shooter ----/ said:
The only thing SS tumbling causes is more friction between bullet and case due to clean case mouths. When using walnut, you still have residues left in the case mouth which act like a lubricant. SS removes all of this and will FEEL like increased neck tension. As to your shaved bullets, if you haven't changed anything else in your loading procedure other than SS cleaning, I'd say your necks are getting too thick and require turning.

Peening your brass with SS pins in water with a mostly sliding action of pins against brass, I've got a lovely bridge to sell you.
Click to expand...

The peening is caused by the cases tumbling through the water against each other. The longer they are tumbled, the worse they get. So if the cases are chamfered too much, they will have more peening. In my experience it's best to go easy on the chamfering, and keep the tumbling to a minimum.
Works for me.
 
curseyou said:
I cant confirm your experience. Though my setup may differ. My neck turned winchester brass are the same thickness .011" as measured by a mitutoyo ball micrometer before and after tumbling in a frankford for 3 hrs. I also see zero change in neck tension from my reference round I made whem I was corn cob tumbling and rounds made now w ss tumbling.

Though I also dont get shavings when seating bullets. .223 or .308, win brass, hornady match bullets. Could something be wrong with your expanding mandrel in you neck sizing die? Maybe it is seated too high?
Click to expand...

I use a case neck gauge from Redding. My neck on 300 win brass is .015 thou so I use a .336 bushing to achieve a .002 thou tension on the bullet. My final measurement on a loaded round is .338.
Neck .015 x 2 =.030
Bullet diameter =308
Bushing is a .336
Total diameter of loaded round is .338 which would give 2 thou tension on the bullet
 
Let me add that I don't turn necks ever and the run out on the brass is always under a half thou.
Also I SS the brass before and after resizing and no sizing button used on the type s die.

I have never experienced any of the problems mentioned by others
 
To actually get peening happening, you'd have to have the brass smashing into each other much harder than SS tumbling with 3/4 full water filled drum can achieve.


I've been using SS tumbling for several years and never encountered these problems you describe.

My regimen includes;
1. Size and deprime.
2. SS tumble with drum 3/4 or more full of water, sunlight and pinch of Lemishine for 3 hours.
3. 170F drying on cookie sheet for 1 hour.
4. Trim to length and debur.
**If needed** Anneal followed by tumbling again for 1 hour followed by drying.
5. Prime.
6. Load
 
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I use ss media to clean my brass after depriming. I bought a hornady sonic cleaner to clean gun parts, turns out to be a little to small, and now use it to clean the brass of case lube after sizing
 
Shooter, I don't know what to tell you. I believe you when you say you have not noticed it and haven't had any issues. You should believe me that I have noticed it on my brass. Minor as for the most part the trim removes anything.

I've since adjusted the ways I ran my tumbler to minimize it. How else can a case go into a tumbler with great looking case mouths and then come out without. I've reduced brass count, increased pins, played around with various water levels, reduced tumbling time, etc. It happens, and I think it's case on case contact. I don't know for sure but it's not like there's some magic happening in there.

If you are curious, smack a case mouth with another case. My experience is it doesn't take much force. Sometimes just using its own weight seems to do the trick.

*shrugs* At the end of the day, I've seen peening so I know it can happen, but it doesn't affect my loading. Per the OP's initial problem, I'd love for him to update us when he's got it under control. If I'm wrong, a lesson learned: cool.
 
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