Will an undersize sizing die increase neck tension?

T

TruthTellers

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I've got these 100 grain Speer "plinker" bullets that are half jacketed, half lead round nose. They're meant for .30 Carbine and other .308 groove rifles, but since it's jacketed and can take high velocities, I'd like to use this bullet in .327. The problem I'm having is the bullet's diameter is measuring .3075" and .327 is meant to use a .312 bullet, so after sizing and with a minimal flare, there still isn't enough neck tension once I seat and crimp the bullet.

I've never found the need to buy an undersize sizer die before, but this may be one load I think I'll need to. Does an undersize size die squeeze the neck enough to increase the tension?

Also, given the brass is being worked more, how much shorter will the case life be after using an undersize sizer? My intention is to load these hot as that's the point of using this jacketed bullet.
 
Under size sizing dies only size the base more. What you need is something to make you bullets fatter. No amount of work to get the bullet to fit in the case is going to confront the issue of using bullets too small for the bore.

If you really want to use those bullets, what you need is a bushing size die with a bushing matched to your brass and bullet diameter.

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Generally,your sizing die will size the neck undersize.Then the actual size is set by drawing the case over the expander plug...with a 3 die set that would bell,too.

I don't know that your die will give you enough initial size down,but 32ACP uses .308 bullets. It might be that you could get a 32ACP expander .Call your die mfgr.

You might get results you are happy with,but my hunch is,a 30 cal bullet that is .0045 undersize is not going to perform well. You aren't going to find a cartridge case reloading die that will make the bullet fit the bore.

You might be able to "shim them up" .002 or so with powder coat.

As I recall,proper size 32 cal jacketed bullets ,bith JHP and JSP are relatively cheap.There are also plated bullets,maybe.

I've been known to spend a dollar trying to save a dime. When it works,it generally doesn't work as well as spending the dime.

But as long as you are having fun....
 
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HiBC said:
Generally,your sizing die will size the neck undersize.Then the actual size is set by drawing the case over the expander plug...with a 3 die set that would bell,too.

I don't know that your die will give you enough initial size down,but 32ACP uses .308 bullets. It might be that you could get a 32ACP expander .Call your die mfgr.

You might get results you are happy with,but my hunch is,a 30 cal bullet that is .0045 undersize is not going to perform well. You aren't going to find a cartridge case reloading die that will make the bullet fit the bore.

You might be able to "shim them up" .002 or so with powder coat.

As I recall,proper size 32 cal jacketed bullets ,bith JHP and JSP are relatively cheap.There are also plated bullets,maybe.

I've been known to spend a dollar trying to save a dime. When it works,it generally doesn't work as well as spending the dime.

But as long as you are having fun....
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Firstly, I don't care about fitting these bullets to the bore, I want them to fit the case with better neck tension. Once that's achieved I'll do the job of finding what it takes to get the bullets to shoot as well as possible.

Originally I was going to use these bullets in my Henry rifle, but everything with these bullets works against using it in that rifle. Besides, it's not like I can't use hard cast, gas checked bullets instead.

The Sp101 is a different story, it's pretty much a jacketed only option if I want to load it hot and the good news is the groove diameter for my SP101 is .310, not .312. .0025 under groove diameter is not terribly bad, a lot better than .0045. It's not like I'll be shooting at long distance with these handloads, I'll save the XTP's for that, but I do want something that I can load hot and not get leading from the high velocity and the oversize throats.

The simplest solution would be if Berry's would get it in gear and start making some thick plated .312 bullets for revolvers, but they only want to make .32 ACP bullets, so I'm stuck working with what's available.
 
reddog81 said:
The sizing dies is irrelevant if your using a expander die is too big.
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Right. I think the only way around it is some fabricobbled solution or a custom die. I don't think anyone is making bushing dies for 30 carbine

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nhyrum said:
Right. I think the only way around it is some fabricobbled solution or a custom die. I don't think anyone is making bushing dies for 30 carbine

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I looked, didn't see any. That doesn't mean I couldn't try a .30 carbine expander die tho.
 
Scratch that, I thought you were using them in 30 carbine, which I thought you were saying was 312 bore. My reading comprehension is lacking
 
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I think the 32 acp size die backed way out is your best bet. I personally wouldn't go much forget than that just to use up a single box of bullets for blasting ammo.

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AsI suggested earlier,whatever brand dies you are using to load 327.order just the expand/bell plug for about any 308 bullet handgun cartridge.

I'm not sure how the lengths work out,but you have adjustment. Something like 32 ACP,30 Luger,30 Mauser.30 carbine

Call your die co,ask what 308 expander plug you can assemble and use in your 327 die.
 
nhyrum said:
Under size sizing dies only size the base more. What you need is something to make you bullets fatter. No amount of work to get the bullet to fit in the case is going to confront the issue of using bullets too small for the bore.

If you really want to use those bullets, what you need is a bushing size die with a bushing matched to your brass and bullet diameter.
Click to expand...

An undersize sizing die will undersize the entire case. That's what they are made for.

The issue is whether there is one that will work with 327 Federal.
 
TruthTellers said:
I've never found the need to buy an undersize sizer die before, but this may be one load I think I'll need to. Does an undersize size die squeeze the neck enough to increase the tension?
Click to expand...

An undersize die should do what you want, but as noted you will likely need a smaller case mouth expansion die.

Here a description of Lee's undersize die,

"Lee U Carbide Undersized Sizing Dies are great for reloaders looking for ultimate feeding reliability in their handgun. These dies undersize brass between .002" and .003" smaller than other Lee Carbide Sizing dies. Ammunition with undersized brass cases will chamber each and every time it is loaded out of a magazine giving reliable chambering each time a round is stripped out of the magazine or loaded into a cylinder. Competition shooters rely on having ammunition that will feed and chamber each round of ammunition as it is stripped out of the magazine. One of the other benefits reloaders have reported when using Lee U dies is increased consistency and accuracy in loaded rounds because these dies help increase and provide more consistent neck tension on loaded bullets. The solid carbide insert inside of these dies is ground to a special contour that does not leave a belt mark on the case. These carbide dies do not require lubricant while resizing, though a little case lube will make the sizing process easier. Shellholder sold separately.

Notes:

Carbide sizing dies do not require case lube
Undersized dies size brass between .002" and .003" below specifications, so ammunition will feed in chamber in tight chambers
Undersized dies work great for bringing back case tension to hold bullets on cases that may be thinner walled"



The 32 ACP undersize die might work for you. Check with Lee.
https://leeprecision.com/undersize-sizing-die-32-acp-s-w-long.html
 
I have the .32 ACP Lee die set, so I'll have to check the expander plug on that later. I never use it when loading .32 ACP because the Lyman M die works much better, but I have no reason to believe the .32 ACP's plug is meant for .308 bullets. American .32 ACP ammo is almost always .312, it's 7.65 that is .308 I think.
 
"....327 is meant to use a .312 bullet..." A .308" bullet is too small.
"...32ACP uses .308 bullets...." Um, no. It uses wee tiny .312" bullets.
 
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