|
|
06-08-2019, 04:10 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Quote:
Originally Posted by Dean2
So you are telling me you have never had to trim cases because they got too long? If you have ever trimmed cases then the brass stretched and a standard trim amount is 10 to 15 thou depending on the case.
|
Dean, I am talking about stretch in the case above the case head. We are talking about the shoulder moving ahead 16 thou. Not the case mouth.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-08-2019, 06:04 PM
|
Banned
|
|
Join Date: Jun 2007
Posts: 4,158
|
|
It is common to have a bunch of case expansion on first firing. Either on new brass or in factory ammo.
How you treat your brass on future sizings and loading is what will determine its life.
Load it up and shoot it. Don't waste time with false shoulder fireforming or waste components imo.
|
06-08-2019, 07:09 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Quote:
Originally Posted by Deer Hunter
It is common to have a bunch of case expansion on first firing. Either on new brass or in factory ammo.
How you treat your brass on future sizings and loading is what will determine its life.
Load it up and shoot it. Don't waste time with false shoulder fireforming or waste components imo.
|
Have you ever in your life measured brass movement?
The sloppiest chamber I have in the safe has exactly three thousandths of an inch clearance with virgin brass. Yes, 0.003. Like I said, if it’s a problem it’s easy to see and prove definitively.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-08-2019, 07:23 PM
|
Banned
|
|
Join Date: Jun 2007
Posts: 4,158
|
|
Quote:
Originally Posted by chuck
Have you ever in your life measured brass movement?
The sloppiest chamber I have in the safe has exactly three thousandths of an inch clearance with virgin brass. Yes, 0.003. Like I said, if it’s a problem it’s easy to see and prove definitively.
|
BS
You will get much more then that in forward shoulder movement. I don’t care what new brass you use, or how fancy of chamber you have. In your life.
|
06-08-2019, 07:32 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Quote:
Originally Posted by Deer Hunter
BS
You will get much more then that in forward shoulder movement. I don’t care what new brass you use, or how fancy of chamber you have. In your life.
|
How much money do you want to put on that?
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-08-2019, 07:41 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-08-2019, 08:52 PM
|
Banned
|
|
Join Date: Jun 2007
Posts: 4,158
|
|
Quote:
Originally Posted by chuck
How much money do you want to put on that?
|
What are we betting on here?
|
06-08-2019, 09:02 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Quote:
Originally Posted by Deer Hunter
What are we betting on here?
|
DH. There are a BUNCH of people here that will confirm that two and three thousandths of an inch head space on virgin brass is COMMON. This is not a big secret. Just wow.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-08-2019, 09:13 PM
|
Banned
|
|
Join Date: Jun 2007
Posts: 4,158
|
|
Quote:
Originally Posted by chuck
DH. There are a BUNCH of people here that will confirm that two and three thousandths of an inch head space on virgin brass is COMMON. This is not a big secret. Just wow.
|
https://www.brownells.com/aspx/learn...aspx?lid=11470
Quote:
. Unfired brass checked in at 1.622" or well below minimum chamber and case spec. Factory ammo, from several sources ran 1.620"; shorter still. Brass fired in my Winchester Model 70 measured 1.630" and brass from my .243 Browning BLR measured 1.631". My brilliant deduction is that new case handloads and factory cartridges see as much as .011" headspace in my firearms when initially fired, and that is substantial as headspace goes.
|
http://www.larrywillis.com/headspace.html
Quote:
Case head separation is much more common with belted magnum calibers. This is partly because ammunition manufacturers always make their belted magnum loads to headspace on the belt. They also leave the shoulder extremely far from contacting the chamber (sometimes as much as - . 020" to - . 030"). This causes the first firing of belted cases to stretch quite a lot. Your very first firing has now stretched your case considerably, and this weakens cases at the expansion ring
|
|
06-08-2019, 09:26 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Have you read ANYTHING I have written here?
Thanks for proving my point regardless.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 02:23 AM
|
|
|
|
Join Date: Dec 2008
Location: Near Edmonton
Posts: 14,972
|
|
Quote:
Originally Posted by chuck
Have you read ANYTHING I have written here?
Thanks for proving my point regardless.
|
Chuck
You are intentionally being difficult. Putting a false shoulder on a piece of brass does not stop the actual shoulder from moving forward whatever distance it was originally short. It also doesn't stop the body from expanding to touch all contact points of the chamber. The false shoulder you are talking about does absolutely nothing to reduce case stretch on brass where the actual shoulder is anywhere from .010 to .030 short of making contact with the shoulder of the chamber. Whether the case head spaces off the belt, or the false shoulder is completely irrelevant to the total amount of case stretch you end up with.
I have never seen you admit you are wrong in any post I have ever read of yours, you just keep spinning it and avoiding the issue. Let it go, you are wrong and no amount of nonsense is going to change that.
|
06-09-2019, 07:36 AM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Laughing. Read the last paragraph above your last post. Yea, I’m wrong. Sure.
Again, I tend not to post about things I have no clue about.
Dean, do you have the tools to measure brass movement?
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
Last edited by Pathfinder76; 06-09-2019 at 07:46 AM.
|
06-09-2019, 07:57 AM
|
|
|
Join Date: Sep 2008
Location: Parkland County, AB
Posts: 4,249
|
|
[QUOTE=chuck;3987268]Laughing. Read the last paragraph above your last post. Yea, I’m wrong. Sure.
Again, I tend not to post about things I have no clue about.
It appears you did just that .
__________________
When applied by competent people with the right intent, common sense goes a long way.
|
06-09-2019, 08:05 AM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
For the third time. This is EXTREMELY easy to see if there is a problem. Load a case and fire it. Section it. Case head separation is hard to hide. No stretch, you are good. Stretching? You decide what you are comfortable with.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 08:08 AM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
[QUOTE=Salavee;3987275]
Quote:
Originally Posted by chuck
Laughing. Read the last paragraph above your last post. Yea, I’m wrong. Sure.
Again, I tend not to post about things I have no clue about.
It appears you did just that .
|
Would you resize a case, any case, by pushing a shoulder back 0.016? If yes, I’ll move along. If no, why wouldn’t you do that?
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 08:15 AM
|
|
|
Join Date: Sep 2008
Location: Parkland County, AB
Posts: 4,249
|
|
[QUOTE=chuck;3987280]
Quote:
Originally Posted by Salavee
Would you resize a case, any case, by pushing a shoulder back 0.016? If yes, I’ll move along. If no, why wouldn’t you do that?
|
No, I would not because I've never had a good reason to do that. I also have a comparator and a yardstick.
__________________
When applied by competent people with the right intent, common sense goes a long way.
|
06-09-2019, 08:17 AM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
[QUOTE=Salavee;3987283]
Quote:
Originally Posted by chuck
No, I would not because I've never had a good reason to do that. I also have a comparator and a yardstick.
|
Salavee, the OP has brass that someone has sized with 0.016 of headspace. What should he do?
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 08:26 AM
|
|
|
Join Date: Sep 2008
Location: Parkland County, AB
Posts: 4,249
|
|
[QUOTE=chuck;3987284]
Quote:
Originally Posted by Salavee
Salavee, the OP has brass that someone has sized with 0.016 of headspace. What should he do?
|
First of all I would confirm the .016 of headspace
__________________
When applied by competent people with the right intent, common sense goes a long way.
|
06-09-2019, 08:29 AM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
[QUOTE=Salavee;3987287]
Quote:
Originally Posted by chuck
First of all I would confirm the .016 of headspace
|
It has been confirmed. What do you do?
In my mind there are three options for salvage.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 08:35 AM
|
|
|
Join Date: Sep 2008
Location: Parkland County, AB
Posts: 4,249
|
|
[QUOTE=chuck;3987291]
Quote:
Originally Posted by Salavee
It has been confirmed. What do you do?
In my mind there are three options for salvage.
|
Im my mind, I would get the headspace corrected and start over.
__________________
When applied by competent people with the right intent, common sense goes a long way.
|
06-09-2019, 08:38 AM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
[QUOTE=Salavee;3987294]
Quote:
Originally Posted by chuck
Im my mind, I would get the headspace corrected and start over.
|
So it is a problem?
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 12:28 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Apology accepted.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 02:18 PM
|
|
|
Join Date: Nov 2009
Location: East Central Alberta
Posts: 8,315
|
|
I’ve been watching this with interest and trying to apply logic to the “what’s happening with the case as pressure does it’s thing”. One thing is certain, that being that the shoulder expands against the chamber wall regardless of whether the cartridge is held back against the bolt by a belt, through proper headspace on the shoulder, or by a false shoulder. And, after the first firing the fire formed case then head spaces at the shoulder unless it is bumped back to the original belt headspace. The question is “from where is the brass required to move the shoulder come from”?
I know from creating a Dasher from 6BR where I use a false shoulder to hold the base against the bolt face, that the bulk of the brass required to move the shoulder forward over 0.090” is just “rearranged” from the neck. That is obvious because the resulting neck is much shorter than pre-fired. It is also obvious that the case body has not just been stretched ... at least not to the extent that it would thin case walls near the web given that another 20+ firings (at arguably very high pressures), does not result in case head separation. It is even possible to see the “ring” at the original shoulder position. ( At this point, I should say that not all Dashers are formed using false shoulders as many keep the cartridge snug against the bolt face simply by jamming the bullet solidly into the lands.)
What I am having difficult understanding, is “why” belted cases would stretch just forward of the belt as opposed to the stretch in the shoulder area.
__________________
Old Guys Rule
|
06-09-2019, 03:05 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Quote:
Originally Posted by 260 Rem
I’ve been watching this with interest and trying to apply logic to the “what’s happening with the case as pressure does it’s thing”. One thing is certain, that being that the shoulder expands against the chamber wall regardless of whether the cartridge is held back against the bolt by a belt, through proper headspace on the shoulder, or by a false shoulder. And, after the first firing the fire formed case then head spaces at the shoulder unless it is bumped back to the original belt headspace. The question is “from where is the brass required to move the shoulder come from”?
I know from creating a Dasher from 6BR where I use a false shoulder to hold the base against the bolt face, that the bulk of the brass required to move the shoulder forward over 0.090” is just “rearranged” from the neck. That is obvious because the resulting neck is much shorter than pre-fired. It is also obvious that the case body has not just been stretched ... at least not to the extent that it would thin case walls near the web given that another 20+ firings (at arguably very high pressures), does not result in case head separation. It is even possible to see the “ring” at the original shoulder position. ( At this point, I should say that not all Dashers are formed using false shoulders as many keep the cartridge snug against the bolt face simply by jamming the bullet solidly into the lands.)
What I am having difficult understanding, is “why” belted cases would stretch just forward of the belt as opposed to the stretch in the shoulder area.
|
For the same reason your dasher cases would without a false shoulder. Set the false shoulder on your dasher 20 thou back and fire it. Then section that case and have a look.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 04:50 PM
|
|
|
Join Date: Nov 2009
Location: East Central Alberta
Posts: 8,315
|
|
Quote:
Originally Posted by chuck
For the same reason your dasher cases would without a false shoulder. Set the false shoulder on your dasher 20 thou back and fire it. Then section that case and have a look.
|
Not going to fire anything with that much head space. How about you just explain it?
__________________
Old Guys Rule
|
06-09-2019, 05:03 PM
|
|
|
Join Date: May 2007
Posts: 15,777
|
|
Your answer just did all necessary explanations. Thank you.
__________________
“I love it when clients bring Berger bullets. It means I get to kill the bear.”
-Billy Molls
|
06-09-2019, 05:11 PM
|
|
|
Join Date: Sep 2015
Posts: 1,816
|
|
There is some merit to the false shoulder as to minimize the stretching of the brass and how it is stretched compared to expanded . Is it worth the effort it appears most are not concerned with it . To others it something they want to eliminate .
|
06-09-2019, 09:43 PM
|
Banned
|
|
Join Date: Jun 2007
Posts: 4,158
|
|
Saami spec on the 338 win mag is specified with up to 15 thou clearance between the belt on the cartridge and on the belt cut into the chamber.
And up to 26 thou clearance between the cartridge and chamber at the shoulder.
Other cartridges that headspace off the shoulder only usually have up to 13-14 thou clearance between the Saami spec cartridge and the Saami spec chamber.
338 win mag factory loads fired from a model 70 have grown 25 thou on the shoulder compared to the factory loaded ammo, according to my measurements. You can see the shoulder growth in the picture. The OP had 16 thou which is very little to worry about imo.
Cartridge, brass and rifle manufacturers build good sized tolerances into their product. And life goes on.
|
06-10-2019, 12:48 AM
|
|
|
Join Date: Sep 2007
Location: Strathcona County
Posts: 1,939
|
|
Quote:
Originally Posted by Deer Hunter
Saami spec on the 338 win mag is specified with up to 15 thou clearance between the belt on the cartridge and on the belt cut into the chamber.
And up to 26 thou clearance between the cartridge and chamber at the shoulder.
Other cartridges that headspace off the shoulder only usually have up to 13-14 thou clearance between the Saami spec cartridge and the Saami spec chamber.
338 win mag factory loads fired from a model 70 have grown 25 thou on the shoulder compared to the factory loaded ammo, according to my measurements. You can see the shoulder growth in the picture. The OP had 16 thou which is very little to worry about imo.
Cartridge, brass and rifle manufacturers build good sized tolerances into their product. And life goes on.
|
Take a closer look in the expansion ring area - above the belt. The case looks fairly shiny. Is that horizontal line a crack developing or is that just a mark from your chamber?
|
06-10-2019, 08:13 AM
|
Banned
|
|
Join Date: Jun 2007
Posts: 4,158
|
|
Those loads were 70's vintage 250 gr silvertips. The brass was dull and showed the mark you were seeing better than if it was new. A crack associated with the weak or thin case head usually appears a bit higher up ime.
I looked at a bunch of old fired factory ammo and that shinny mark on top of the belt is there in most cases, some more obvious than others. Brass moving forward is the likley reason. But that is completely unavoidable with undersized factory ammo.
|
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -6. The time now is 05:03 AM.
|