Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Reloading

Reloading Techniques For Reloading


Reply

neck tension on a 7mm Allen

 
LinkBack Thread Tools Display Modes
  #8  
Old 12-14-2010, 02:41 PM
Platinum Member
 
Join Date: Jun 2001
Location: Potomac River
Posts: 5,057
Re: neck tension on a 7mm Allen

Quote:
Annealing is then performed to normalize springback in that batch of cases, and NOT to increase tension. Your sizing/firing takes care of that.
You should have quit typing after the first post if you didn't know what you are talking about.
__________________
The Smokin Fur Rifle Club
Reply With Quote
  #9  
Old 12-14-2010, 06:44 PM
Gold Member
 
Join Date: Dec 2002
Location: mathias wv
Posts: 985
Re: neck tension on a 7mm Allen

Quote:
Originally Posted by Mikecr View Post
Again, annealing reduces the stress that provides springback, and tension.
'Heat-treating' makes metal harder. This is not 'annealing', which always means to make metal softer(or stress relieved). Brass cannot be made harder by heating it--ever.
Brass is always made softer by heating, and the only way brass can be made harder is to 'work' it. With softer brass(freshly annealed) there is LESS springback, and LESS tension.

You typically know it's time to anneal when a few cases in a batch exhibit EXCESS tension, as seen with splitting necks or seating force variance.
Annealing is then performed to normalize springback in that batch of cases, and NOT to increase tension. Your sizing/firing takes care of that.

Given your annealing method described(totally wrong), and apparent lack of tension, the cause and affect is pretty clear. Cycle the brass a few times(Size/expand/fire) to regain normal springback, and stop annealing for a while.
less springback equals less tension?? WTH, mike how can that be? nevermind just wrote off any post where you give reloading advise.
RR
__________________
Born to Hunt, Forced to Work!
Reply With Quote
  #10  
Old 12-14-2010, 09:38 PM
Platinum Member
 
Join Date: Aug 2003
Location: NC, oceanfront
Posts: 3,174
Re: neck tension on a 7mm Allen

Well, before you write it off, you might consider that springback IS your tension.
And that it's exactly all the tension you have.

When you seat a bullet, you are upsizing a neck. What holds that bullet in place is the SPRINGBACK from this upsizing, which tops out at 1.5-2thou interference depending on the brass work hardness, and regardless of 'oversizing'.
Don't believe me?
Measure a normally sized & loaded neck OD. Pull the bullet, measure unloaded OD & neck down further an extreme amount,, say another 5-6thou under. Now seat a bullet. It will be very difficult to seat because of all the upsizing you're doing here, but once seated the loaded neck OD measures the same as before.
So now, is there greater bullet grip than normal?
NO THERE IS NOT
Pull the bullet, and measure how much the neck springs back. It will be 1-2thou under, with the same unloaded OD as with normal sizing. That is your tension, and it's entirely springback.

Now do the same right after annealing, and you will measure LESS springback after pulling the bullet.
If you over anneal a case, there will be maybe a half thou springback, to none at all...
This is LESS tension.
Further annealing will not fix this. The necks will have to be re-work hardened to regain normal springback.

That's about as much effort as I care to waste here...
Reply With Quote
  #11  
Old 12-14-2010, 10:18 PM
Gold Member
 
Join Date: Dec 2002
Location: mathias wv
Posts: 985
Re: neck tension on a 7mm Allen

Quote:
Originally Posted by Mikecr View Post
Well, before you write it off, you might consider that springback IS your tension.
And that it's exactly all the tension you have.

When you seat a bullet, you are upsizing a neck. What holds that bullet in place is the SPRINGBACK from this upsizing, which tops out at 1.5-2thou interference depending on the brass work hardness, and regardless of 'oversizing'.
Don't believe me?
Measure a normally sized & loaded neck OD. Pull the bullet, measure unloaded OD & neck down further an extreme amount,, say another 5-6thou under. Now seat a bullet. It will be very difficult to seat because of all the upsizing you're doing here, but once seated the loaded neck OD measures the same as before.
So now, is there greater bullet grip than normal?
NO THERE IS NOT
Pull the bullet, and measure how much the neck springs back. It will be 1-2thou under, with the same unloaded OD as with normal sizing. That is your tension, and it's entirely springback.

Now do the same right after annealing, and you will measure LESS springback after pulling the bullet.
If you over anneal a case, there will be maybe a half thou springback, to none at all...
This is LESS tension.
Further annealing will not fix this. The necks will have to be re-work hardened to regain normal springback.

That's about as much effort as I care to waste here...
ok, my interpretation of springback

you resize a work hardened brass, as you pull the case out of the sizer it springs back, that make sense?
now an annealed soft case, doesn't spring back as much when you pull the case out of the die, make sense?

now the case that doesn't spring back as much has a smaller hole to stuff the new bullet in, am I correct?

so which has more neck tension? the one that sprang back or the one that didn't?
RR
__________________
Born to Hunt, Forced to Work!
Reply With Quote
  #12  
Old 12-15-2010, 08:47 AM
Platinum Member
 
Join Date: Aug 2003
Location: NC, oceanfront
Posts: 3,174
Re: neck tension on a 7mm Allen

Quote:
Originally Posted by Ridge Runner View Post
so which has more neck tension? the one that sprang back or the one that didn't?
To begin, seating force and springback are different and seperate things.
If it springs back less on down sizing, it will springback less on upsizing as well, causing less grip on the bullet, even if harder to seat(single pass upsize).

If the sizing was sufficient and similar in both cases(the bullet is still upsizing with seating), the case which sprungback more will provide greater bullet grip(tension). It is springing back from seating -to cause grip.

The case with no springback MIGHT cause more seating force with greater required upsizing on seating(probably not). But it will also provide LESS springback to grip the bullet once seated, because it's softer.

I know, we describe bullet grip as tension, which is described as an interference fit..
This is just another of many assumptions we make, that are wrong.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: neck tension on a 7mm Allen
Thread Thread Starter Forum Replies Last Post
Even neck tension ltrshooter Reloading 6 04-20-2011 12:42 AM
Neck tension-- how much ??? GNERGY Reloading 8 10-12-2010 05:35 PM
neck tension rufous Reloading 3 08-24-2007 08:57 PM
neck tension col48 Reloading 8 05-02-2006 12:51 PM
Neck Tension? tdv75098 Reloading 6 02-13-2005 07:04 PM

Current Poll
How Many Different Cartridges Do You Reload For?
ZERO, all factory ammo - 8.02%
352 Votes
1 - 2.78%
122 Votes
2 or 3 - 14.55%
639 Votes
4 or 5 - 20.38%
895 Votes
6 or 7 - 14.83%
651 Votes
8 or 9 - 8.65%
380 Votes
10 or more - 30.79%
1,352 Vote
Total Votes: 4,391
You may not vote on this poll.

All times are GMT -5. The time now is 07:21 PM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC