Too much neck tension New Lapua brass

[Dub]

I am having issues with new Lapua brass in 6.5x47. I have read all threads relating to this but still seek guidance. I run the new brass over a mandrel expander die and use Imperial dry neck lube but the first load is very heavy in neck tension. Are these just throw away loads?

 

[RichMoAK]

Shoot 'em and move on.

 

[LCazador]

Seat the bullets into the lands and fireform with a moderate load.

 

[Jdne5b]

I also run new brass through a dry tumbler to help add some dust to the necks, chamfer, and mandrel.

Maybe go .0005 bigger in mandrel for a little less tension? Or some Hornady One-shot on the necks will also help if the high tension number you're seeing is friction related more than actual tension.

 

[skeeljc]

Do you leave the dry neck lube in after you expand the neck? Virgin brass will produce a high seating force. The carbon in the neck after multiple firings acts as a lube.

 

[Dub]

this load is set 6 thou off the lands

 

[Dub]

Do you leave the dry neck lube in after you expand the neck? Virgin brass will produce a high seating force. The carbon in the neck after multiple firings acts as a lube.

i guess my question is whether or not to use these in competition

 

[skeeljc]

i guess my question is whether or not to use these in competition

It depends on how well they shoot.

 

[LCazador]

this load is set 6 thou off the lands

Seat into the lands when fireforming so the bullet holds the case against the bolt face for a good fireform. I would fireform at least once before using for competition.

 

[Dub]

i will not likely use these in competition but it goes against the grain when one uses all the available tools to make a load and yet something is very wrong

 

[Old Navy]

Bigger expander always works for me.

 

[Sandstorm]

Had the same problem with some Norma brass for my 284 Shehane...I was gonna pull them all,
however they shot fabulously...so go and try them first. You may be surprised or. not.??
I always shoot my new brass in Competitions and never had a problem other than the nut
pullin the triggger..lol

 

[1911mag]

Have a 6.5x47 being built so watching this

 

[Ned Ludd]

When you open up case necks from the inside with a mandrel, the brass spring-back works in the opposite direction than it does when you tighten them down from the outside with a FL sizing/bushing die. Based on the normal diameter of the bullet, you need a mandrel of approximately 0.0015" smaller than bullet diameter to give you a neck tension (interference fit) of ~.002", because the brass shrinks about half a thousandth more after the mandrel is withdrawn from the neck. If you use a mandrel that is a full .002" under bullet diameter, you will end up with more than .002" neck tension. Thus, use the bullet diameter, subtract the desired neck tension, then add back about .0005" to estimate the appropriate mandrel diameter.

 

[1911mag]

Thanks sir

 

[Sandstorm]

I use a .2835 mandrel in a .284 case and its perfect.

 

[Dusty Stevens]

Did you fl size them then fireform? Anything goes until then and theyre not suitable for competition until then

 

[bozo699]

Anneal the brass just a tad bit hot and then run the mandrel through them.

Definitely not!....
Wayne

 

[Kymike]

try a 21st century on size mandrel. Use mica dry lube inside case neck. You may have to run it over the mandrel a couple of times. I do not want to use scarce and valuable reloading components for fire forming rounds. We should be able to craft very good ammo with all new components I have had the same problems with Lapua 260 brass. Necks were so tight that it was causing pressure problems.

 

[1911mag]

Did you fl size them then fireform? Anything goes until then and theyre not suitable for competition until then

I always Fl size brass new prior to fire form.