Fat Boolits and Neck Tension

[longbow]

Not too long ago I was having some trouble getting consistent accuracy from my .303 using the NOE 0.314" x 129 gr. lapped to 0.316" then sized to 0.315" to suit a Lee Enfield with 0.314" groove diameter.

One day while loading I was looking closely at the loaded rounds and it seemed that I could see a bit of a bulge around the gas check in the neck so I wondered about neck tension swaging the driving bands.

Some pulled boolits told the tale. This boolit has fairly narrow driving bands so easily distorted by a tight neck (ACWW).

Then it occurred to me that the RCBS expander button was likely quite small so I mic'd it and found it was about 0.310" which would be right for a factory spec rifle shooting "J" bullets at 0.311"/0.312".

Since I am using fat boolits at 0.315" this tight fit is not only hard on boolits but also works the brass unnecessarily.

My temporary solution was to make a new expander button at 0.314" to see if accuracy improved. It did. Probably no surprise.

By the way, I have the die backed out so am just neck sizing and I anneal often.

So, I decided to buy a Lee collet sizer and give it a go. Well, for some reason I thought it was all adjustable or came with different mandrels but no. The mandrel is 0.3085" so again suitable for factory spec chamber and "J" bullets but tight for my fat bullets.

I made a new mandrel at 0.3135" and tried that. Success! I may have to polish it down another 0.0005" to 0.001" but with freshly annealed brass they come out at about 0.314".

Now I won't be working the brass so badly by sizing way down then opening back up, and I have the right neck size.

This may also explain some of the poor PP accuracy I was getting using my RCBS dies with the original expander button giving excessively tight neck.

My NOE 316299 didn't seem to be affected by the tight neck or not as much anyway... maybe due to beefier driving bands.

Maybe I should have realized this some time ago but it wasn't a real problem until I got the new mould.

By the way, I am quite happy with the Lee collet sizer, it works very well (especially with the larger mandrel to suit my needs). I also picked up a Lee universal case mouth flaring die too which also works very well. Both are well made and work.

I haven't loaded and shot yet but will shortly. I am sure accuracy will be improved and my brass will be much happier.

I would figure this must be a pretty common problem with many generous milsurp chambers and groove diameters where fat boolits are used.

How many others are having similar problems and how did you solve them?

Longbow

[Larry Gibson]

Found the same problem some years back. I solved it by getting a Redding '06 bushing die and shortening it a bit. I can use different size bushings to give .002 neck tension on cartridges from the 6.5-06 up through the '06 including the 7.65 Argie, 7.7 jap and the .303 Brit.

Larry Gibson

[longbow]

Larry:

I will have to check out the Redding bushing dies. I am not familiar with them. From your description, I assume it just squeezes from the outside?

No complaints about the Lee collet die though it seems to work pretty slick. Didn't take long to make a new mandrel either. I just turned one with a step up to 0.314" then polished down a bit and used a needle roller for a decapping pin.

Whoda thunk an old Dodge universal joint could provide useful bits for reloading?

I can make more mandrels at different sizes quite easily if I want to play some more.

Longbow

[longbow]

Larry:

I just took a look at the Redding bushing dies so I guess I answered my question. From what I see they appear to use just a bushing to swage the neck.

So, varying brass thicknesses would require neck reaming/turning to same thickness or a selection of bushings to suit. Of course if neck thickness varies much they should be turned or reamed to same thickness anyway... I guess I am stating the obvious and no different than a standard full length or neck sizing die.

Looks like a nice rig but considerably more expensive than the Lee.

Is there any advantage over the Lee collet die or of the Lee over the Redding? I like the idea of squeezing onto a mandrel but then that is from a relatively uneducated guy.

I have been at this boolit casting and reloading thing for quite a while but am still learning all the time.

Longbow

[303Guy]

Mmmm ...... My solution was to make my own neck sizer dies with a separate expander for cases that needed more sizing to get them to fit the chamber. With a given batch of brass it's not too difficult to outside size only to get the correct internal dimensions. The problem comes in later when I no longer know which die is for what!

[largom]

The advantage of the Redding bushing die's are first, they are very high quality and you can obtain bushings from .185 thru .368 in .001 increments. The advantage of the Lee collet die is very low cost but unless you can make your own mandrels you are stuck with the factory size. I have a couple of the Lee dies and like you I have had to make my own mandrels. I also have numerous Redding die's and a good assortment of bushings which I use for calibers that I am trying to obtain utmost accuracy from. I also use the Redding bushings in a push-thru sizing die I made for sizing cast boolits.

The Redding bushing die's are made for the benchrest shooters and to benchrest standards, therefore the high cost. Most all benchrest shooters turn case necks.

Larry Miller

[craig61a]

I have ordered custom mandrels from Lee for my collet dies. They are $10 ea. and since I don't have a lathe it's my only option right now. I lapped out the sleeves to accept the larger sized mandrels. One of these days I gotta find an old benchtop tool room lathe...

[Char-Gar]

No serious reloading room is complete with one of these gizmos....

[Larry Gibson]

I don't neck turn most case necks as commercial cases are actually quite uniform for most rifles. For those rifles that can tell the difference I do neck turn. I use the size of bushing that will size them down for .002 - .003 neck tension, sometimes .001 -.002 with softer alloys. If there is a .001 difference inside diameter the GC take care of that when seating. On some I size .001 under the M-die expander size and it sizes the inside correctly.

The Lee Collet die makes sense with different collets if you are just loading for one cartridge. However if you are loading for various cartridges like I am the Shortened Redding '06 Bushing die makes better sense. Take a moment and consider how many cartridges I can NS with ming; off the top of my head I count 8 different cartridges that I NS for with that one die and various bushings.

With minimally sized cases and the use of a Lyman VLD type inside neck reamer flaring the case mouth with an M die or the lee tool is not necessary either.

Larry Gibson

[longbow]

I figured the Redding was a class act in quality and looks it.

As for the Lee mandrels, if you have a lathe (I do) then making a mandrel is easy. I didn't want to alter the Lee parts so made a stepped mandrel from 0.3135" to 0.3085 at the top to fit the collet sleeve. I guess I could have reamed the collet sleeve out to the largest size I might want then step down to the mandrel size required so drop in as original. Anyway, this worked and was easy. I drilled and tapped the mandrel from the top and installed a retaining screw.

I guess for different cartridges, the Lee might need different collets so that would likely make the Redding more attractive.

I have tried just inside neck chamfering with no case mouth flair but found I had problems shaving lead... but then that was with the tighter neck and maybe a bit steeper chamfer angle than the Lyman VLD tool. Maybe I will have to give that a go.

Anyway, what I have works for now. The larger neck size certainly helped with accuracy and the Lee collet sizer with larger mandrel will be kinder to the brass. Win, win!

Still lots to learn and lots to try yet too.

Longbow

[runnin lead]

For 7.5X55 Swiss I use a Lee Collet Die with a .303 British mandrel.
For 30-06 & 308 Redding bushing neck size dies,Lee neck expander/ flair & Hornady seater with .303
British alignment sleave.

[Char-Gar]

I have a custom made expanding plug for an M-Die that has steps that are .001 different from .307 to .317. In use I run it in far enough to be able to insert the gas check into the case mouth and then seat the bullets. It has worked well for me with cast bullets from .310 to .315.

[Mk42gunner]

Larry,

If you were getting your first bushing die today, wouldyou still go with the '06 die and shorten it, or would you go with one for one of the short mags?

I am sure I will eventually end up with a bushing die and a whole lot of bushings.

Robert

[n.h.schmidt]

Hi
I have three Lee Collet die sets. I have used my 303 die without a mandrel at all.
You can adjust the die to size any amount you want. I lately size the necks to .312 . I measure this with my calipers. This is perfect for my PP boolits that are sized to.314. A little tricky to get adjusted just so as the die thread is not all that fine. If I do this ,I do have to provide a seperate way to decap. I also do this with my 308 die and a spacer so I can neck size my 7.5 french cases to just be a good fit for my cast boolits.
n.h.schmidt

[longbow]

I wondered about sizing without the mandrel but haven't checked adjustment yet. With the coarse threads I can see that getting within a thou or so of what you want might be tricky.

If you were to turn down or polish down the mandrel to smaller than required, then you would get the adjustable sizing through die adjustment but still have a decapper.

I was just curious as to how many others accommodated fat boolits for oversize chambers and bores and what they did about it.

My home made expander button worked well but is hard on brass when sized back to factory specs then opened up for the fat boolits. The Lee collet die with custom mandrel should provide correct neck size and be gentle on brass.

The Redding looks like a good system too. I have not seen those as I live in a reloading desert. Not much around for 3 or 4 hour drive. If you know what to look for I guess you can always find it on the internet.

That's why I asked. Still lots to learn and many people have different methods, ideas and equipment.

As always, these discussions are educational.

Longbow

[no34570]

Hi Longbow
How did you make the new expander button? and the Mandrel,any pictures?
Wish I had a lathe,would Lee Precision make these???
Thanks

[longbow]

no34570:

Yes, I can post some photos. Not much to the expander button. I used a portion of a head bolt from a Chevy 327, annealed, turned to match the RCBS expander button (except larger diameter) then drilled and tapped to screw onto the end of the decapping rod. After it was finished I heated red and quenched but didn't temper. Works fine.

The mandrel was also pretty simple. I used a chunk of cold rolled for that since there is no wear, turned to diameter, tapered the decapping, drilled a 1/16" diameter hole and drove in a needle roller from a used Dodge universal joint as a decapping pin. It is a little larger diameter than the Lee or RCBS decapping pins but fits through a flash hole so works fine.

I'll see if I can get some decent photos tomorrow and post.

Longbow

PS: Here is a photo of the "new" bits.

On the left is my home made mandrel stepped from 0.3135" to 0.3085" to fit the Lee bushing which I didn't want to alter. I drilled and tapped the top for a retaining screw since it has to be pushed in from the bottom instead of dropped in from the top like the Lee. You can just see the step above where the brass rubs on the sizing portion.

Next is the Lee stock mandrel with "mushroomed" head.

Second from right is the RCBS decapping rod with my homemade expander button.

On the right is the stock RCBS expander button

[longbow]

Should have realized editing didn't bump to top.

[no34570]

Thanks for that,cool

[ReloaderEd]

I have a set of lyman/Ideal 310 Large handles that I use to expand the inside necks of rifle cases. The expander dies were made specifically for castbullets and can be adjusted to slightly bell the case mouths so one will not shave bullets when seating. I use a light crimp which works well and they shoot fine in the M1 or other bolt rifles. Case length must be kept the same length. Just a thought. Be Safe