Lee collet die vs. rcbs neck die

[trazman]

Hey guys, I have the .300 win mag lee collet die and rcbs neck sizing die which is better and why?

 

[Dr. Vette]

Try both and see.

I've used both for a 7mm magnum, and the loads shot identically. I could not tell the difference with that ammo in that rifle.

Having said that I would generally put a neck bushing die ahead of a collet die for repeatability, and I'm contemplating a Redding bushing die for my 270 since I can't get what I want with a Lee collet die with regard to consistent neck sizing.

 

[woods]

LEE COLLET

PROS - straighter ammo (less runout), no lube in neck, more consistant ID
CONS - less bullet grip (unless you order a smaller mandrel or sand one down), learning curve

RCBS EXPANDER TYPE NECK SIZER

PROS - no learning curve
CONS - lube in neck, more runout


UHHH...................Lee Collet much better IMO

 

[SidecarFlip]

Lube in neck? Not here, never. NADA.

I like them both actually.

 

[DocB]

LEE COLLET

PROS - straighter ammo (less runout), no lube in neck, more consistant ID
CONS - less bullet grip (unless you order a smaller mandrel or sand one down), learning curve

Sir, would you mind elaborating a bit on this. How would I go about determining the amount of grip being applied and what size smaller mandrel would be needed for 300WM? By sanding down a collet mandrel, wouldn't that increase the ID on the mandrel somewhat?

Thanks,

DocB

 

[Kevin Thomas]

I am still at a complete and total loss as to the fascination with Neck Dies. Problems, plain and simple, just looking for a place to happen. They don't increase accuracy over F/L sizing, and assuming the F/L dies are set up properly, they don't add a bit of case life.

 

[woods]

Sir, would you mind elaborating a bit on this. How would I go about determining the amount of grip being applied and what size smaller mandrel would be needed for 300WM? By sanding down a collet mandrel, wouldn't that increase the ID on the mandrel somewhat?

Thanks,

DocB

The amount of grip is up to you. General consensus is bullet grip from .001" to .003" (less than diameter of bullet)

You can get an approximation of bullet grip by measuring outside neck diameter of a sized but unloaded case and a loaded case, subtract the 2. Not very accurate

There are other tools. I use a set of pin gauges

You can order mandrels from Lee in whatever diameter you want (minimum order applies, $15.00 or more IIRC)

Some prefer to chuck the mandrel in a drill and hold sandpaper on it. I had miserable results with that, hard to get consistent results from top to bottom and keep it perfectly round, YMMV

 

[SidecarFlip]

Hell with sandpaper, chuck it in a 5C spin index, mount the spin index on your mag chuck and grind it to size. Of course you need a surface grinder to size it...we have one of those.....

An alternative would be to use a toolpost grinder and your lathe and collet closer attachment. Have that too,

 

[DocB]

Dang... You guys got all the neat toys!!

DocB

 

[Bodywerks]

LEE COLLET

PROS - straighter ammo (less runout), no lube in neck, more consistant ID
CONS - less bullet grip (unless you order a smaller mandrel or sand one down), learning curve

RCBS EXPANDER TYPE NECK SIZER

PROS - no learning curve
CONS - lube in neck, more runout


UHHH...................Lee Collet much better IMO

Agreed, unless he's talking about their bushing dies. Bushing dies have the potential to form truer.

 

[SidecarFlip]

Bushing dies are a bit hard to get. I order direct from RCBS and Redding and I've experienced backorder situations lately....

 

[Bart B]

I am still at a complete and total loss as to the fascination with Neck Dies. Problems, plain and simple, just looking for a place to happen. They don't increase accuracy over F/L sizing, and assuming the F/L dies are set up properly, they don't add a bit of case life.

Me too, but I'm convinced the reasons they do neck size is they don't understand how bottleneck cases headspacing on their shoulders fit the chamber aligning the bullet with the bore when fired as well as how firing and sizing changes the case shape and dimensions.

One common thinking is neck sized cases fit the chamber better than full length sized ones as they rest on the chamber bottom when fired. Sierra Bullets put this reason in one of their loading manuals years ago. I mentioned this to Martin Hull and he laughed.

 

[trazman]

So what are you guys saying that it is better to full size in a proper way or I dont understand something?

 

[Bart B]

Yes, it's better to properly full length size bottleneck cases.

What do you think centers a .308 round's bullet in the bore when the primer fires and starts burning the powder before the bullet moves?