TRIMMING: before or after sizing?

[Majopikeras]

Hi all!

I normally trimm the cases after the sizing step.

But today i have had problems with 264 WM cases.

When i size it (hornady new dimension full size die) the shoulfer collapses (seems to get "star" shape)

I unscrew a few turns the die, and sized a few cases. But when i tried to trimm this cases (to 2,490"), the neck becomes too short. I have other 2,490 long cases with longer necks.

Thanks in advance... Hope you understand the post, my english isn´t as good as i want...

 

[flashhole]

Sounds like your brass is becoming work hardned. You might try annealing the cases and see if the situation improves. The way you wrote your post leads me to believe things were good at one time and recently you have problems. That's why I'm suggesting annealing.

 

[boomtube]

Your Engliish if fine. Wish my 55 year old high school Spanish was as good!



We normally trim cases after sizing, we do not care how long a fired case is.

Do not know if annealing would help your problem.

 

[JOSE A. MARINE]

the star shaped shoulder you are getting could be from excesive oil near the neck before sizing.

when you pull the die up(unscrew), you are only partially neck sizing, so even if you have the same lenght in all the cases, some have less real neck to work with.

JOE FROM MEXICO.

 

[Majopikeras]

Thanks all!

Sorry, but i don´t know what´s annealing! Can someone explain it?

Talking about the excess lube oil... I use just a little, and the die has a hole to wipe the excess.

I have tried other method: I have trimmed 5 cases BEFORE sizing it. I have trimmed it to 2,490, after the full sizing, they size 2,4905 to 2,491 and the neck is longer.

When i trimmed it the neck seems too short, after the sizing it look´s much better.

My hornady 7th edition reloading guide and the lee deluxe rifle sets told that you have to trim before sizing.

Any other idea? I think this is a good way to go!

Thanks all again!

 

[flashhole]

Trimming before sizing is going againt conventional wisdom. The case will grow in length as it is FL sized. After it has grown to its full length via the sizing process is when you should trim it, not before.

 

[flashhole]

Annealing the process of applying heat to the brass to soften it. This is usually done with a torch. There are plenty of threads on this forum that discuss annealing, try a search. Note that you only want to anneal the neck and shoulder area of your brass since they are manufactured and treated to be harder at the base. Annealing the base can cause a case rupture. You can often times see the discoloration from annealing in the neck and shoulder area on new factory ammo. It only takes a few seconds with a torch to get the brass up to its annealing temperature and soften it. You can also look on You Tube for annealing processes.

 

[One_Duck_Limit]

the star shaped shoulder you are getting could be from excesive oil near the neck before sizing.

when you pull the die up(unscrew), you are only partially neck sizing, so even if you have the same lenght in all the cases, some have less real neck to work with.

JOE FROM MEXICO.

I agree with Joe. It sounds like you have excess oil in your die. The dents are formed by hydrolic pressure.

 

[JOSE A. MARINE]

ANNEALING, tratamiento termico del material donde la intencion es suavizar el material. idealmente se alarga la vida util del laton.

YouTube - Cartridge Annealing Machine

un video ojala te sirva de algo.


JOE from Mexico

 

[kc]

I like to measure first than trim if its over size and if I re-use the brass I trim 1/2 MM under size.
Also welcome from the USA. Your English is just fine. Its good that you have joined this forum.

 

[7 loader]

Clean your die watch your lube. Aneling will help to. As Marine stated to much lube will cause this.

 

[kc]

7 loader is right,,