Will an undersize sizing die increase neck tension?

[T-Unit]

Firstly, I dont want people recommending me other bullets that are larger. I have a project I'm working on and that's my focus. Also, I've shot the .30 Carbine bullets in .327 one at a time before with good results, but using the smaller bullets presents a challenge.

Here's the deal: I'm trying to use .30 Carbine bullets in .327 because they're the cheapest bullet I can get that can handle the high pressure and velocity of .327, but the issue is the bullet diameter is smaller than what .327 normally uses. Because of this I'm having an issue where after neck expanding using either a .327 or .30 Carbine expander, the bullets are loose after seating and crimping for some reason makes them looser.

I had done a dummy round last week to see how the tension was and it looked promising, but when I got to loading I wanted the bullet deeper in the case, so I did that only to find when I did the neck tension was lost.

This makes no sense, but it is what it is.

Now I'm wondering if using an undersize sizer will help give me the tension I want to hold the bullet in place. My thinking is if the outside of the case is made smaller that will make the inside as well.

I don't plan to run the undersize die the full length of the case, just the portion the bullet would be seated to and I would still use the .30 Carbine expander.

 

[TrashcanDan]

It might.

Case neck on the .30 shows .336 and the .327 shows .337

2 different diameters as I'm sure you know. An undersizer might buckle the case if not run down all the way?

What are you using for a crimping die, and have you tried a .30 cal die.

I'm sure this will end splendidly.

 

[milktree]

Sizing die happens before neck expansion, so how could a smaller die, followed by the same neck expander, increase tension?

For straight wall cases the power die will expand the mouth in addition to belling it, and for bottle neck cases the expander button does it.

Am I missing something about your setup?

What crimp die are you using?

 

[DW357]

Sizing die happens before neck expansion, so how could a smaller die, followed by the same neck expander, increase tension?

For straight wall cases the power die will expand the mouth in addition to belling it, and for bottle neck cases the expander button does it.

Am I missing something about your setup?

What crimp die are you using?

I’ve started using a Lee undersize die for 357 and 44 mag since I’ve reloaded the brass so many times (and I load warm) and the tension was getting loose. Works great.

No experience with 327

 

[TrashcanDan]

I’ve started using a Lee undersize die for 357 and 44 mag since I’ve reloaded the brass so many times (and I load warm) and the tension was getting loose. Works great.

No experience with 327

Am I missing something about your setup?

What crimp die are you using?

The issue hes having is loading .308's into a case designed for a .312.
Its like loading 9mm jacketed into a .38 spl case flared out for .358's. Things will walk right out probably some decent velocity loss.

 

[milktree]

The issue hes having is loading .308's into a case designed for a .312.
Its like loading 9mm jacketed into a .38 spl case flared out for .358's. Things will walk right out probably some decent velocity loss.

So, use an expander button/powder die for the smaller bullet, right?

 

[T-Unit]

It might.

Case neck on the .30 shows .336 and the .327 shows .337

2 different diameters as I'm sure you know. An undersizer might buckle the case if not run down all the way?

What are you using for a crimping die, and have you tried a .30 cal die.

I'm sure this will end splendidly.

Lee for the crimp die, that's what came with the .32 revolver 4 die set.

I don't have concerns about case buckling, I still plan to full length size with the standard sizer, but run the undersizer a quarter of an inch down from the mouth. I figure that works the brass less and it's not like I'm using worn out brass, I'm using fresh Starline cases.

 

[T-Unit]

Sizing die happens before neck expansion, so how could a smaller die, followed by the same neck expander, increase tension?

For straight wall cases the power die will expand the mouth in addition to belling it, and for bottle neck cases the expander button does it.

Am I missing something about your setup?

What crimp die are you using?

This is what I was thinking as well and why I didn't immediately get the undersize sizer at the same time I ordered the .30 Carbine expander as I wanted to test and see if the expander alone would make a difference.

It does up until crimping or seating the bullet too deeply, and I'm using the Lee factory crimp die. I would love to use a collet style crimp, but Lee doesn't make one in the .32 caliber.

I have measured the ID of the case after sizing with the standard sizer and IIRC it measures to .308, but with no flare I can't put the bullet into mouth and if I try to force it during seating it crumples the case. IDK what happens to the ID of the case if an undersize die is used during sizing, but I can't imagine the ID doesn't also get smaller as the OD gets smaller.

One thing I should probably mention is that so far the only bullet I've used is the Speer half jacket "Plinker", so it may just be that particular bullet is the issue and it has a diameter closer to .307 than .308.

Problem right now is .30 Carbine bullets are hard to come by and I don't care to blow $130 on 1000 Berry's bullets that might have the same problems.

 

[T-Unit]

So, use an expander button/powder die for the smaller bullet, right?

That's what I tried and still not quite enough. I guess I could try again but not seat the bullets so deeply, but then if I don't put a crimp on the bullets they will back out of the case under recoil rather quickly. Even the ones I seated deeper but didn't crimp only took a few shots to get them to pull of the case a little. I don't like that, I want bullets that stay in place for consistency.

 

[milktree]

That's what I tried and still not quite enough. I guess I could try again but not seat the bullets so deeply, but then if I don't put a crimp on the bullets they will back out of the case under recoil rather quickly. Even the ones I seated deeper but didn't crimp only took a few shots to get them to pull of the case a little. I don't like that, I want bullets that stay in place for consistency.

OK, I think I misunderstood the situation.

I believe (and I'm not 100% confident of this, more like 80-90%) that the expander button/ powder die is the only thing expands/sets the case to the appropriate diameter... BUT... only if it has been sized down sufficiently by the sizing die.

i.e.: if the sizing die doesn't compress enough, then it just doesn't matter what the button/powder die are sized to.

I had a problem with a particular brand of 9mm brass that was just a smidge too thin walled, combined with a sizing die that was just a smidge too big. It was all Dillon stuff, so when I asked them, "hey, what's wrong here?" they sent me a new, slightly smaller (or maybe sized correctly) sizing die and the problem went away.

So....

In the context of your changing the expander WITHOUT changing the sizing die, I think your assertion that a smaller sizing die would make the neck tension higher, is true.

 

[DW357]

Seems like a PITA.

You can get 100 gr 32 cal bullets for 5.5 cents each shipped. You paying less than that for 30 carbine bullets?

I’ll shoot you a PM on the vendor

 

[T-Unit]

Seems like a PITA.

You can get 100 gr 32 cal bullets for 5.5 cents each shipped. You paying less than that for 30 carbine bullets?

I’ll shoot you a PM on the vendor

The price is great, but this operation seems like they get what they can and there's no guarantee they'll get the same bullets again in the future. At least with Berry's and Speer .30 Carbine bullets they've been making them for decades and will make the exact same bullets for many more decades to come.
I will certainly buy these bullets if the undersize sizing die fails to deliver the results I'm seeking because at that point I'll have tried everything possible.

 

[TrashcanDan]

So, use an expander button/powder die for the smaller bullet, right?

Maybe
At this point, because of the size difference, an expander or powder funnel might be counterproductive. From the looks of it, the .308's might plop right in after sizing. Sounds like too much slack even after undersizing.
Probably better off just charging the cases one at a time.
No guarantee anything will come out concentric either.
Spec shows a crimp difference of .001, but the diameter difference says theres probably a case thickness difference.
That lee crimp die that comes in the 4 die set is one of those seat/ crimp dies. Its the only one in there out of the 4 that does a double function, even though theres already a separate seat die.
Its in the fine print in the instructions.

Probably way less frustrating to just trade the .308's for .312's and be done with it

 

[DW357]

The price is great, but this operation seems like they get what they can and there's no guarantee they'll get the same bullets again in the future. At least with Berry's and Speer .30 Carbine bullets they've been making them for decades and will make the exact same bullets for many more decades to come.
I will certainly buy these bullets if the undersize sizing die fails to deliver the results I'm seeking because at that point I'll have tried everything possible.

I guess. But you could buy all 5k that they have for $275. That will last you a bit lol

 

[T-Unit]

I don't blow that kind of money on something that isn't proven. Same reason I won't buy 1k Berry's bullets that I've never previously tried before.

 

[DW357]

I don't blow that kind of money on something that isn't proven. Same reason I won't buy 1k Berry's bullets that I've never previously tried before.

True. Yeah I’d try 1k and see how it goes from there.