case flaring verse bigger expanderball

[Tertle]

sorry guys for my ignorance but there is a great post on flaring the case mouth and i dont want to hijack the thread, it has answered a couple of my questions alraedy but i need to ask a newbie question or two.

Im loading for a .308, i gas check as well. i size to .309 but find ocasionally that some of my projectiles get shaved, if i only flare the mouth wont that just mean that somewhere else in the neck of the case i will be sizing down again the projectile

or

would i be better to use the next cal up expander ball and crimp the neck after seating the projectile?

and can you get expanderballs that are marginally bigger than common cals that will allow for good neck tension as well?

hope this makes sense!

[Mk42gunner]

sorry guys for my ignorance but there is a great post on flaring the case mouth and i dont want to hijack the thread, it has answered a couple of my questions alraedy but i need to ask a newbie question or two.

Im loading for a .308, i gas check as well. i size to .309 but find ocasionally that some of my projectiles get shaved, if i only flare the mouth wont that just mean that somewhere else in the neck of the case i will be sizing down again the projectile

Possibly, but I have loaded quite a few .308 Winchesters with ACWW boolits sized .311" by flaring the neck with the neck expader from an RCBS .30 Carbine die set.

or

would i be better to use the next cal up expander ball and crimp the neck after seating the projectile?

I'm going to say no on this, you still need to have neck tension to hold the boolit in the case, for proper ignition.

and can you get expanderballs that are marginally bigger than common cals that will allow for good neck tension as well?

Lyman's M-dies do just what you are describing; however I don't know how much they would end up costing you after shipping and the exchange rate. They aren't that hard to make if you have access to a lathe. Dean Grennel shows many of his homemade ones in his ABC's of reloading series.

hope this makes sense!

Hope the way I answered makes sense to you.


Robert

[Tertle]

Robert, thanks for the reply, i will look up M dies now and yes you made great sense.

the thing is the old pacific Peso is doing reasonably well at the moment verse US dollar so i am thinking of getting some bits in from the states, if i can find a decent place to get them from and work out best options for freight!

[Calamity Jake]

For most of my 30 cal. cast case neck sizing I have gone to the Redding bushing neck size die with 308 bushing neck die and 3-5 bushings I can cover 308 and 30-06 for 3-5 boolit diameters.

By adding the proper bushings and using the 308 die I can also necksize 6.5X55 &
7MM mauser/7X57. Then I use a 60° inclusive angle (30° per side) counter sink to inside chamfer the case mouth, never have to flair again and no boolit shaving while seating.

The Lyman M die is a good and I still use too.

[Doc Highwall]

The Lyman M-dies are the way to go.

[mroliver77]

You can get other expander balls. Sometimes you must go to the next larger caliber and then reduce the ball to your required size. Most dies reduce the neck too much requiring the sizer to expand it back open. This is hard on brass! On my .308 for instance I use the Redding bushing die. I size to approx .003 smaller than boolit size and then the ball (or m die) opens it .001 to end up with .002 of difference(fit). I use the ball to open a bit to make up for differing brass thickness. If using turned necks this step could be omitted.

If I am using the Dillon and doing large batches I use the M die and omit the sizer ball. If I am making a small batch for accuracy I cut a taper like Jake does.
Jay

[mdi]

I would look at the flare. You needed neck tension for consistant ignition and holding the bullet in place. Normally .002" or .003" difference in case/bullet diameter won't swage normal hardness bullets. I've used different tapered tools for flaring the case mouth like a center punch (about 25 degrees) up to a countersink (turned backwards, 60 degrees) and anything in between. (When I had access to a lathe I turned down some 7/8-14 bolts to a taper and just used that instead of a die.) Of course these mostly have been used by hand so it may seem slow to some. Some I used with a sm. hammet and some I used like a "case iron", just push and twist against the case mouth. And of course, try the M-Die.

[runfiverun]

i have bought expander balls in different sizes for some rcbs dies like a 310,311.
but i don't think they make them in one thou increments you'd have to have that done yourself.

i champher the case mouth and flair the case mouth to seat.
you need some neck tension to hold things securely in place.
how much you are squishing the boolit in the neck is something you are gonna have to measure and decide if it's truly harming the boolit yourself.
if it's too much you can work with your same dies by thinning the necks the amount you think you need.

[onondaga]

Tertle And runfiverun

There is another way to get the excellent effect of the Lyman "M" Die in some calibers for cast boolits. I load 7.62X39mm and my boolits are sized .312" . I use the Lee Collet Neck sizing die modified my adding a mandrel from a .303 Brit Collet die...a $4 part. After I size with my customized neck die then I case mouth flair with the Lee Universal expander.

This gives me the inside neck diameter that is correct for my cast gas checked boolits and the flair allows them to start seating very easily. In this particular load I finish up with the Lee Factory Crimp die but only use it to bring the flair back to neutral and don't crimp as my rifle is a single shot break open Remington Spartan and I don't need a real crimp.

The Lee .303 Brit collet mandrel will work in a Lee .308 collet die also. you will have to shorten it to the same length as the original one in your die as I did.

My press is a 4 station turret. 1) size, de-prime. Then off press to trim/shamfer. Back on press to prime. Off press to charge. 2) Expand case mouth 3) seat bullet. 4) crimp.

Gary

[geargnasher]

The "M" die is the way to go, for sure. IF you have Lee dies, you can get an expander stem from a .303 British die set, it will be about .310", but you will still have to have a tool to bellmouth the case. The advantage of the "M" dies are that they make an oversized "step" at the top of the mouth, not just a bell, so your boolit gets started straight.

Gear

[Doc Highwall]

With the Lyman M-die you do not even have to chamfer the case mouth just remove burrs, that is all I do.

[Harter66]

I make pins for my RCBS universal decaper that flair and decap in1 pass and as needed expand necks. It became needed for my 06' with its need for a .310 neck id and the very loose 7.62x39 that needs a boolit at .318,papper patched to .320. The hardest thing about turning the pins is getting the die threads square and the flair/bell shoulder just right. I turn mine from hardware store round stock on a drill press w/a couple of files 2 paper grits and some steel wool,1/4-28 die too.

[nanuk]

how can one modify an M-die for an intermediate size?

say, you have a large bored .31cal and are using a NOE GB 316299?

[jmsj]

how can one modify an M-die for an intermediate size?

say, you have a large bored .31cal and are using a NOE GB 316299?

nanuk,
If Lyman doesn't offer the size you need, you'll either have to try and sand or machine the next size up down to the size you need. Another option is to build or have someone build the the expander to the dimensions you need.
In the past I have been able to make my own M-die and Lee expanders on a lathe at work. It is kind of a fun project.
Good luck, jmsj

[Tertle]

Hey thanks for all the great info, i will sit back and have a good read!