Lee collet die not sizing neck like I thought it would.

[bruddah]

So I was neck sizing my virgin Lapua .308 brass with my new Lee collet die and everything seemed to be going well. The Lapua brass was actually possibly tighter already than the Lee die was sizing to as it took a little bit of force to push the neck past the mandrel up into the die.

Anyways....

I grabbed a once fired .308 case off of my reloading bench (something I probably just picked up at the range), wiped it clean and ran it up through the die. TO my surprise, it have a larger measurement (diameter across the neck) than the Lapua brass did coming out of the die.

Not only that, but in one instance the bullet actually had zero interference when sliding it into the neck of one of these fired cases. It would literally slide in and out. Why is this?

Additionally, I was noticing a small vertical scratch on the necks of the Lapua brass after running them up through the Lee collet die.

Any help greatly appreciated!

 

[bruddah]

P.S. I set the die up exactly per the instructions included with the die set.

 

[jagged77]

Your virgin brass will have necks tighter than a virgins proverbial... When you are using the Lee die to round them out prior to first firing they are springing back to a degree - hence the tightness around the mandrel.

You need to set the die up again for your once fired brass to ensure the collets are doing their job. I setup mine so the press bottoms out (sizing the case at the bottom of the stoke). This seems to give more consistent results. Check out these instructionals: Lee Collet Neck Sizing Die Part 1 - YouTube

Vertical marks down the case neck are normal for the collet die. You can go a little way to avoid them by using a small amount of lube. It also helps to put some grease on the outside of the collets just where it fits into the cup.

 

[Brux]

Had problems with mine also.When I bought the set and I did not know or was informed that you could not use this neck die with a cam over press like my RCBS.

 

[pinsandpitons]

You can use them on cam-over presses... at least I did with success, but one needs to be careful with the set up so as not to damage the die. The directions are great, but only a starting point to understand the die and how it works. Also it helps to have turned necks, and use the same lot of brass.
[MENTION=39339]bruddah[/MENTION] I bet neck thickness has something to do with your results as well.

 

[Fuzzball]

Instructions get us in tbe ball park; we have to adjust our tools according to the effect. Main thing to grasp about the collect neck die is we must put enough force on the necks to conform them to the mandral and stop there; no amount of additional pressure will further reduce the neck's inside diameter.

I've happily used Lee's collet dies in a 'Chucker for some 25 years. Either I don't know what I'm doing or those who tell you not to do it don't know what they're doing.

There's nothing special about "cam over"; all it means is the press' body bumps that limit movement of the lever/toggle block are cut back enough to allow the toggle to rotate slightly passed the ram's full up position.

Without knowing if the 'neck scratches' are on the inside or outside I won't hazard a guess what's causing them.

 

[DGD6MM]

I use Lee Collet Dies on every cartridge I shoot that Lee makes them for. With that being said, Lee instructions are simple, to adjust to your press follow accordingly, may need to tweek a little. I have a Lee Classic here at home I've been using for 7-8 years now. Before the Lee I had a Hornaday Pacific, over the weekend I set my cousins RCBS Rockchucker up with my .308 Collet Die. All 3 presses are different but following the instructions they adjust easily. AS Fuzzball stated extra force will not achieve any better results. I size then rotate my case 1/2 turn and size a second time per instuctions. The vertical marks you speak of, if they are on the outside of the neck are from the collet. I've heard of this , but have not seen it.

 

[Rprecision]

I have never had a problem with mine.

They are ment to be set at camover, otherwise its like pissing in the wind and trying to keep the piss off your boots

 

[Brux]

Good to know this I will have to give mine another chance.I called Lee and they are the ones that told me it would not work with my press.

 

[FLIGHT762]

I've set my Collet die to cam over using the instructions from post #3 @ benchrest central: Lee Collet Die Adjustment.

I've also used it as Lee describes in their instructions, they recommend not to use cam over with the collet die (#2 on the instructions)

http://leeprecision.com/instructions.html Click on Collet die instructions, 4th down.

Either of the settings has worked well for me. I'm using the non cam over style of sizing on a cam over (Lyman Orange Crusher) press.

 

[J-ROD]

I use a Lee press which doesn't cam over. I go by pressure as neck thickness changes versus using ram height.
I size once, lower ram a hair, spin case a few degrees and hit it again. Holding for a few seconds does increase sizing but consist annealing has shown to be more important in my experience

Sent from my XT1080 using Tapatalk

 

[Kirkd]

I had same problem. May need to adjust die and make sure that you push down hard on on the handle.

 

[gigamortis]

Virgin Lapua brass has always had a neck ID smaller than the standard collet die mandrel for me. Out of the box Lapua .308 brass runs about .003 neck tension for me. Strangely, my best ever F-class score at 1k was with virgin Lapua brass loaded straight out of the blue box it came in. I shot a 198-5x that day with my 20" Savage 10fp topped with a fixed power 10x SWFA SS scope!

After that performance, I measured the IDs of the remaining unloaded Lapua brass of that lot and found that they were giving me .003" neck tension out of the box. So I polished down the mandrel in my collet die until I was able to obtain the same .003" neck tension after springback. Most reloading critics may scoff at that much neck tension, but I can't argue with results. I shot another F-class match at 1k with the annealed once fired brass from the previous performance sized for .003" neck tension and shot a 197-7x. .003" neck tension is definitely working for me.

 

[bruddah]

The instruction from Lee say NOT to cam over the die. Bring it up till it touches the shell holder and then turn it down two more full turns.

I still find it off that it wouldn't size the one piece of brass enough to hold a bullet.

I also did the size, lower the ram, rotate 180 degrees and re-size again.

 

[bruddah]

Virgin Lapua brass has always had a neck ID smaller than the standard collet die mandrel for me. Out of the box Lapua .308 brass runs about .003 neck tension for me. Strangely, my best ever F-class score at 1k was with virgin Lapua brass loaded straight out of the blue box it came in. I shot a 198-5x that day with my 20" Savage 10fp topped with a fixed power 10x SWFA SS scope!

After that performance, I measured the IDs of the remaining unloaded Lapua brass of that lot and found that they were giving me .003" neck tension out of the box. So I polished down the mandrel in my collet die until I was able to obtain the same .003" neck tension after springback. Most reloading critics may scoff at that much neck tension, but I can't argue with results. I shot another F-class match at 1k with the annealed once fired brass from the previous performance sized for .003" neck tension and shot a 197-7x. .003" neck tension is definitely working for me.

Interesting, and good to know!

What neck tension does it give from the factory setting?

 

[bruddah]

I also wanted to say thanks to everyone who has chimed in.

You guys have been a GREAT asset. My learning curve has grown exponentially since I started reading these forums.

(and my wallet has exponentially SHRUNK).

 

[pinsandpitons]

What neck tension does it give from the factory setting?

I don't know that one can say for sure, it depends on the metallurgy of the brass in addition to the simple OD of the mandrel and how hard the collet squeezes. ie; tension will change as the springback rate changes... all other things held the same.

 

[bruddah]

Your virgin brass will have necks tighter than a virgins proverbial... When you are using the Lee die to round them out prior to first firing they are springing back to a degree - hence the tightness around the mandrel.

You need to set the die up again for your once fired brass to ensure the collets are doing their job. I setup mine so the press bottoms out (sizing the case at the bottom of the stoke). This seems to give more consistent results. Check out these instructionals: Lee Collet Neck Sizing Die Part 1 - YouTube

Vertical marks down the case neck are normal for the collet die. You can go a little way to avoid them by using a small amount of lube. It also helps to put some grease on the outside of the collets just where it fits into the cup.

Excellent video! Thanks for posting that! I actually watched part one and two and also another consistent crimp video too.
Awesome!

 

[sakobob]

i didn't see it brought up but the mandrel could be oversize.if your problem persist i would measure it, hell i'd measure it any way
for the knowledge of it.

 

[gigamortis]

Interesting, and good to know!

What neck tension does it give from the factory setting?

I was getting .001" to .0015" with once fired annealed brass with my out of the box collet die.