Neck Sizing W/ F/L Dies

[Pistol Ranch]

What are the negatives in using a full length die set to neck size only by backing out the F/L die??

P.R.

 

[steve4102]

Depends on the cartridge and how much taper it has.

 

[gamestalker]

I tried it a long time ago with .270 win. and 7mm rem. mag and couldn't get the neck completely sized down to the shoulder. I've heard of it being done though, so I must have done somthing wrong. I bought neck size dies long ago and gave up having to do any frankenstien loading.

 

[ranger335v]

"I tried it a long time ago with .270 win. and 7mm rem. mag and couldn't get the neck completely sized down to the shoulder."

If we size a case neck to the shoulder with an FL die it's not neck sizing, it's FL sizing. ??

 

[JimKirk]

Partial Full Length Sizing or PFLS can be accomplished with Full Length sizing dies. The body of the brass will get sized "some" ... along with all or "most" of the neck ... you chose whether to set the shoulder back or not by adjusting the die. May not fit your chamber if you don't though.

Jimmy K

 

[Pistol Ranch]

If you are reloading cartridge cases fired in YOUR rifle, it seems that by neck sizing (with F/L dies) shoulder set-back should not be an issue..

P.R.

 

[ranger335v]

"If you are reloading cartridge cases fired in YOUR rifle, it seems that by neck sizing (with F/L dies) shoulder set-back should not be an issue.."

Ah, but no matter what chamber it was fired in, if the body is squeezed it will enlongate and push the shoulder forward, thus it is an issue.

 

[steve4102]

Ah, but no matter what chamber it was fired in, if the body is squeezed it will enlongate and push the shoulder forward, thus it is an issue.

This ^. Same problem many loaders have when they set up their FL dies incorrectly. Failure to make contact with the shoulder will often times push the shoulder forward.

 

[Pistol Ranch]

So educate me..What is to prevent the shoulder moving forward on neck sizing dies only?? The original reason for this post...i.e. whats the difference between backing off a F/L die and using a neck sizing die only.
Assuming that I am reloading once fired cartridges from my rifle..

P.R.

 

[Walkalong]

If neck sizing only eventually you will need a FL die or a body die to bump things back a hair to fix the hard chambering. The other choice with you FL sizer is to partial full length size to fit your chamber. That is what I would suggest doing with the dies you have.



http://www.thehighroad.org/showpost.php?p=6270171&postcount=1

 

[Innovative]

Don't guess at chamber clearance ...

If you want to resize your cases as accurately as possible, you must know the EXACT clearance between the shoulder of your handloads and your particular chamber. This requires one accurate measurement with the Digital Headspace Gauge.

 

[Walkalong]

Larry's Digital Headspace Tool is a superb looking tool and should work great.

Yes, a good tool with a quality caliper or micrometer attachment (Such as Larrys) to measure your finding with fired vs sized brass is the way to go IMHO. There are numerous satisfactory ways to do it. I use some home made gauges as well as a Sinclair tool with calipers. Many folks over the years have taken the firing pin and spring out of the bolt and sized the brass down a hair at a time until there was almost no resistance to the bolt closing. Works just fine.


I have come to believe the way fguffey described to me in my thread is the best way since it should measure on the datum line for the cartridge, but I am not going to toss the home made gauges I have already, as I am sure they are good enough, and have worked well for me.

 

[ranger335v]

"So educate me..What is to prevent the shoulder moving forward on neck sizing dies only?? "

Okay: What moves the shoulder forward in an FL die is contact with the body. Neck dies make no body contact. The issue with using an FL die for NS is, does the case contact the die body and that depends on the actual sizes of the fired cases and the die body.

There is no point in NS below the base of the bullet-to-neck contact. That can let us leave the die body up more than might be assumed.

 

[rsrocket1]

So educate me..What is to prevent the shoulder moving forward on neck sizing dies only?? The original reason for this post...i.e. whats the difference between backing off a F/L die and using a neck sizing die only.

At least with the Lee neck sizing die, there are 4 quarters of a cylinder which close in on the neck when you push all the way down on the die. If you put a case in the die where the neck is covered with soot, you'll see four lines on the neck 90 degrees apart. The only time the die makes contact with the empty case is at the top of the stroke when the sizing ring closes in on the neck (and the depriming rod keeps the neck from getting squeezed too small.

A F/L die is squeezing the body of the case all the way up the die until the shoulder portion of the die starts making contact with the case. The neck portion of the die then oversqueezes the neck. When the depriming rod is pulled back out of the neck, the expander ball opens the neck to the correct diameter. This can pull the shoulder up the case if the shoulder was not bumped back enough. It also can stretch the case OAL so that you would have to trim it down.

 

[Innovative]

rsrocket1 ......

If you only neck size your cases, the shoulder will soon need to be bumped back so your handloads will continue to chamber. (That means your brass is changing size.) Why not make your handloads all the same size? Benchrest shooters are now using FL dies for that reason.

However, most benchrest dies are specially made (expensive) for each rifle. It's important to minimize chamber clearance (at the shoulder), and do it accurately. That extends the life of your cases, and it minimizes run-out. The Digital Headspace Gauge makes ALL of your FL dies work like those expensive benchrest dies by adjusting your die height accurately.

.

 

[Walkalong]

The Digital Headspace Gauge makes ALL of your FL dies work like those expensive benchrest dies by adjusting your die height accurately.

Not exactly Larry. Those dies are generally cut with the reamer that did the barrel. Then we partially FL size bumping the shoulder barely enough, if even enough, to measure. Keeping the growth at bay is more important than sizing any measurable amount. The cases then fit the chamber much much better than when using the same technique with standard dies and standard chambers. Remember, we are also talking about tight neck chambers here as well where the necks are turned to give .001 or less clearance. Much, much, better chamber fit.

Not knocking your gauge. It is a fine tool. It just can't make standard dies for standard chambers work like the custom benchrest sizers you spoke of. It just uses the same technique for measuring shoulder bumping.

 

[Innovative]

Walkalong ......

This is no advertisement, but there are many benchrest shooters using this technique to bump the shoulder the slightest (measured) amount with FL Redding S-Type Dies.

I have encountered non-benchrest shooters that are finding that their case shoulder is actually being extended by FL resizing. This happens when a FL die is too tight (diameter) for a particular chamber. You can get the very most consistent resizing if you measure things ..... no matter what dies you're using.

 

[JimKirk]

Back in the early days, at the beginning of my reloading era, nobody had any of these fancy gauges or tools! I, along with a couple of the older reloader/accuracy "nuts" who are now shooting at the "big range in the sky" ... well they taught me how ... to use the tools we did have. We made sure "our" brass fit our chambers ... NO we didn't know that Joe's or Moe's brass didn't fit a gauge... but we sure did know how to use the one devise that told us what we needed to know... it worked back then ... it still works today!

A simple candle and a little smut!

Reminds me of my Wife's collection of kitchen "tools" ... five minutes to set up a French fry cutter ... that does nothing a good knife would not do... a knife is a lot easier to wash too!

Jimmy K

 

[Walkalong]

Those custom cut dies I spoke of are bushing dies. I own two of them. The Redding dies are very good and some people use them in Benchrest.

Pushing the shoulder forward happens every time we full length size because the body is being squeezed inward before the shoulder is touched. If we have the die adjusted properly it gets pushed back where it should be. If we don't, it doesn't. It can either be too far forward or too far back. No big secret.

You can get the very most consistent resizing if you measure things ..... no matter what dies you're using.

I have never disagreed with that.

 

[Innovative]

It's no secret, but extending the shoulder is a big surprise to many shooters that don't measure their handloads.

I've also measured cases that were resized using the old "soot method", and they aren't anywhere near as close as some shooters think.

.

 

[JimKirk]

I've also measured cases that were resized using the old "soot method", and they aren't anywhere near as close as some shooters think

As close to what? Fitting ??

Larry ...I'm sure that "some" reloaders/shooters are like "some" carpenters ... "that'll do" ...if it touches "that'll do" ! Don't lump us all together!

Jimmy K

 

[Pistol Ranch]

Just to make sure I understand the concept..let me list what I know and have learned from this thread..
When I fire a round in my rifle the brass expands to release the bullet, AND the brass expands to fit the chamber.
As I understand it, the reason for the use of NS dies is to prevent "overworking" the brass.. Since the fired case is now an exact fit in my rifles chamber I only need to rework the neck to allow it to grasp a bullet
in the reloading cycle.
Per Innovative, at some point I will have to "bump" the neck back on my brass
USING A F/L DIE.
So back to my ORIGINAL question..What is the downside of using a F/L die to neck size only since I can use the SAME die to neck size or F/L size..
The use of/need for a digital headspace gage has me confused..i.e. my brass conforms to my rifles chamber once it is fired..it cannot fit my chamber any better than when it is "fire formed" so why the need for a gage??
I am not a benchrest shooter..I reload to get the best accuracy from my hunting rifles..

P.R.

 

[ranger335v]

"As I understand it, the reason for the use of NS dies is to prevent "overworking" the brass.. Since the fired case is now an exact fit in my rifles chamber I only need to rework the neck to allow it to grasp a bullet in the reloading cycle."

In theory, yes, in theory and practice it's supposed to be the same. However, in practice thangs are rarely the same as theory. Thing is, cases usually fail due to split necks and conventional NS dies work the necks as much as FL dies do, therefore the theory is mostly wrong.


'So back to my ORIGINAL question..What is the downside of using a F/L die to neck size only since I can use the SAME die to neck size or F/L size."

In theory, that should work. Fact is, it normally doesn't; meaning it's rare we can actually neck size with an FL die. That's why they make and we buy neck dies if we want to neck size, it's not just a game to add dies to our kits.

 

[Walkalong]

So back to my ORIGINAL question..What is the downside of using a F/L die to neck size only since I can use the SAME die to neck size or F/L size..
The use of/need for a digital headspace gage has me confused..i.e. my brass conforms to my rifles chamber once it is fired..it cannot fit my chamber any better than when it is "fire formed" so why the need for a gage??

You cannot neck size with a full length sizer. It is going to touch the case some in 99% of calibers if you have it adjusted down far enough to size enough of the neck. That means you may push (squeeze) the shoulder forward enough to cause chambering problems. If you have Larry's gauge (or another method) to measure where the shoulder is it will show you this.

So, adjust your full length sizer to bump the shoulder back .001 to .003 for hunting ammo. Or, buy a neck sizing die.

If you use a neck sizing die your cases body and shoulder will not be sized at all. As the case has more and more firings the high pressure hammers the case outward and forward until it gets hard to chamber. that is when you will need a body die or FL sizer to bring it back into a diameter/shoulder to base length that will chamber easily.

For hunting ammo I would not neck size. There is no guarantee that it will be more accurate, and it might even cause a chambering problem when you least need it. I would full length size but use some sort of tool to measure how much you push the shoulder back. For hunting ammo that you need to chamber every time (Even in a cold chamber where the chamber is smaller than your nice comfy reloading room) I would bump the shoulder a minimum of .001, .002 would be better, and .003 would be just fine. With good bullets your rifle likes this method can shoot extremely well. Plenty good enough for 300 yard hunting ammo.

Hope this answers your questions. AC

 

[Innovative]

+1 for Walkalong

I prefer to FL resize ALL of my rifle handloads, but it's important set the die height accurately.