umm need advice on neck tension

[Freedom2live]

Welll folks loaded up some 7mm mag and headed at to range (50) rds.. everything went great except for 3 rds that I touch the bullet and it moved. . Looks like neck tension were loose, but I full sized every single one of them.. its not super loose just enough to push down the bullet.. Question is were these safe to fire ???

Would it blow up since not enough pressure??

 

[tbrice23]

Have you annealed any of those cases?
(Were the bullets .277". JUST KIDDING)

 

[Lefty7mmstw]

I had that (the sliding bullets thing) happen once with win brass and 140 accubonds in my 7stw ammo. I killed an antelope at 300 yards with those rounds (only ammo I had with). Turns out the brass was a bit thin necked for my dad's redding stw dies. Got another set of dies and all is well. If I had collet dies I'd have simply stepped down a collet.
Zero neck tension will change the load a bit from what heavier neck tension will do for you, but the biggest problem lies in the fact that the pill can shift; if you get one at the lands and one set back from recoil the accuracy will go to pot. The one at the lands will likely also have higher pressure as it has no run to the lands.

 

[Freedom2live]

Dear friend thanks for the reply...

 

[backwoods83]

If this is the first time its happened using the same dies, ANNEAL your brass!

 

[Freedom2live]

Yes this is the first time... I bought 100rd of federal brass.. how would I go about annealing brass ??

 

[backwoods83]

A benchsource annealer or the oldschool way of a 600* paste, a handheld torch, and a cordless drill. Google it, there are several methods.

 

[Mikecr]

If your FL sizing included expansion, which it should, then the last thing you need is annealing -for low bullet grip.

Tell us the rest of the story. Why are your sized necks too big.

 

[tbrice23]

No one has asked him how many times the brass has been resized? 10 or more he might need annealing?

 

[Mikecr]

That's right. We don't have enough information to make the call.
How many times, and how much are the necks being sized?
Is there an expander in the die, or necks expanded otherwise?
What are the fired neck diameters?
What are the sized neck diameters?
What are the loaded neck diameters?

 

[backwoods83]

Well you guys are right, there needs to be more info but I naturally assumed (yeah I know) that if he has been using the same sizing die over and over with no prior issues, that he has work hardened his brass and it has lost some of its grip, but there could be other explanations.

 

[tbrice23]

I think he's gone.

 

[Freedom2live]

Sorry folks, its been a long painful weekend. .
A buddy friend passed away and I dont get emails when someones replies to my post..

This brass is new federal brass...never fired. When I opened the bag I noticed a couple of brass necks out of shape, so I run them thru fl sizing.. went to cabelas and bought winchester brass. It looks better than federal brass.

 

[tbrice23]

Very sorry for your loss.




If I cant get lapua brass I use winchester with great results my last batch of 500 win. 7mag I sorted by neck thickness 42 were more than 1.5 thousands out of concentric and all weighed within 5 grains.