once fired too long

arrggg · March 22, 2005, 12:05 PM

about 40% of my once fired brass for .308 is too long, most are around 2.013
but some are 2.020-2.022, max case length 2.015. Does this indicate a problem with the rifle? the brass is federal, winchester, and remington from cheap factory ammo. The rifle is a remington .308, heavy barrel.

**Mike Irwin** · March 22, 2005, 12:45 PM

No, probably not.

Rifle brass will often elongate, even after a single firing.

Trim it back, and go from there.

CaptainRazor · March 22, 2005, 02:26 PM

Generally, even brand new brass it right at the maximum length.

Usually, when I buy new brass, I go ahead and trim it because it's usually to long anyway.

deerhunter17 · March 22, 2005, 02:29 PM

You will just need to get a case trimmer and a Caliper.

G56 · March 22, 2005, 02:32 PM

I agree 100% with Mike, it's quite normal. When reloading rifle cartridges you need to check the length after every firing.

I have been reloading since about 1965, I loaded some rifle calibers but mostly pistol, I started reloading 223 in quantity about a year ago, I started out with a case of military ammo, shoot that up and generate my own once fired brass in the process, my observation is that about 50% of my once fired brass will need to be trimmed, I've been doing a lot of trimming!

arrggg · March 22, 2005, 02:49 PM

ok, thanks for the help

CaptainRazor · March 22, 2005, 05:12 PM

Just for the record, I really HATE trimming cases.

Dave R · March 22, 2005, 06:05 PM

Quote:

Just for the record, I really HATE trimming cases.

Agreed. The least fun part of the process.

Desert Dog · March 22, 2005, 09:02 PM

Drill presses make case trimming a snap...

The job still sucks though... :barf:

DAVID NANCARROW · March 22, 2005, 10:56 PM

I'm not wild about case trimming either, but I do like the Lee zip trim. Resize, chuck the case, insert trimmer, and pull the cord handle.

If you are shooting a bolt rifle, you'll find a lot less trimming with neck sizing your cases.

G56 · March 22, 2005, 11:53 PM

There is a way to take the tedium out of trimming, the only problem is that it's expensive.

http://www.giraudtool.com/prod02.htm

CaptainRazor · March 23, 2005, 01:58 AM

Ouch! That's a bit pricey.

Think I'll just stick with my old Lyman universal, I really don't have to trim much anyway, but it's just so slooooow going.

Anyway, while we're on the subject. I've been having some crimp issues with my 45ACP cases. I spot checked some of my empty brass and sure enough, I'm going to have to trim them.

Now, on to my little problem, I have some once fired stuff, and I checked some of them, and they are below trim to length. As with some of my other brass, I run across a few that are to short as well.
I am certain that they haven't ever been trimmed before.

Any of you guys ever run into this before? If so, what did you do?

Dave R · March 23, 2005, 04:22 PM

I have run across this once. The only option is to shoot 'em until thry grow, right?

I don't notice any major accuracy changes. I suppose it would affect crimp, if you are crimping that brass. But I don't own any rifle brass I need to crimp.

Nnobby45 · March 23, 2005, 06:05 PM

Brass stretches primarily through the full length sizing process and simply has to be trimmed. Don't like trimming?

You have to if you're a handloader. Neck sizing only can prolong the matter, but you'll have to full length size eventually. Bump the case mouths in a sizer, just enough to straighten them out. New cases come dinged up from the factory. New brass doesn't always come from from the factory in uniform lengths. Just trim them all to minimum. Time envolved is a wopping 10 seconds per case after you're set up and running. Make sure you set your trimmer properly. It's really depressing to ruin 50 cases before you realize your mistake!

Then champfer and deburr the case mouth. Mandatory.

For you new handloaders: Where does the extra brass come from that makes the case neck longer? If you don't know the answer, you need to research it until you understand case resizing, case stretch, and head space.

What is an incipient (partial) case head seperation? It's a split (upon firing) at the web of the case because the brass has become thinner during the firing and resizing process. (The crack starts on the inside of the case and you can't see it) Guess where the brass went. Well, it went to the case mouth,that nobody likes to trim, and made it longer or thicker. If you've HAD to trim 4 or 5 times, you might consider that the limit and discard the cases. The brass has simply become too thin near the case head. You can feel the crack inside with a paper clip bent into a hook shape. You should keep a log and know exactly how many times a batch or LOT has been reloaded. When you learn how many times you can trim a case before cracks appear on the inside, then discard them just before you reach that point.

When a case is fired, the case expands tight against the chamber walls and forms a seal. Except for the thicker part of the case at the rear. There, it can only stretch backwards until it is stopped by the bolt face. The amount it has to travel to do that is generally referred to as the head space (not the technical definition). Too much headpace can cause a seperation, (it can only stretch so far without splitting), and so can normally safe headspace if the brass has become too thin there, as described above. If the shoulder of the case is set way too far back through improper resizing, then it can result in a catasrophic full case head seperation ALL of the pressure escapes into the action and can blow up the gun and the shooter. The safety vents can't handle that much pressure.

NOTE: UNDERSTAND the concept of full length resizing! As in: Just enough for the case to fit your rifle so as to reduce case stretch upon firing.

The less serious, but still dangerous, partial head case seperation amounts to a crack all the way through the case where SOME of the pressure escapes into the action, and escapes out the vents on the receiver peppering the shooters face and shooting glasses with powder residue. Can draw blood. Or cause eye damage if shooting glasses aren't worn. Gun damage usually results in a ruined extractor on rifles like the Rem. 700, but usually not more serious than that. Remember that we're dealing, typically, with 50,000 lb. per sq. in. or more of pressure (PSI).

It concerns me when shooters jump into hand loading without learning the basics first, and when they take advice from well meaning, but not necessarily knowledgeable, fellow shooters. Many shooters on the board are very knowledgeable, and some aren't. Be careful.

Nnobby45 · March 23, 2005, 06:55 PM

Sorry about the dbl post

arrggg · March 24, 2005, 09:34 PM

well I shot my first reloads today, I shot 2 five shot groups one measured .542"
the other .560, these were done with lee collet dies, this was a VAST improvement over factory ammo, these were not the best groups they were the only groups, I am quite pleased, thanks for the help.

March 22, 2005, 12:05 PM	#1
arrggg Member Join Date: December 6, 2004 Posts: 22	once fired too long about 40% of my once fired brass for .308 is too long, most are around 2.013 but some are 2.020-2.022, max case length 2.015. Does this indicate a problem with the rifle? the brass is federal, winchester, and remington from cheap factory ammo. The rifle is a remington .308, heavy barrel.

March 22, 2005, 12:45 PM	#2
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,379	No, probably not. Rifle brass will often elongate, even after a single firing. Trim it back, and go from there. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

March 22, 2005, 02:32 PM	#5
G56 Senior Member Join Date: June 10, 2004 Location: Oklahoma Posts: 302	I agree 100% with Mike, it's quite normal. When reloading rifle cartridges you need to check the length after every firing. I have been reloading since about 1965, I loaded some rifle calibers but mostly pistol, I started reloading 223 in quantity about a year ago, I started out with a case of military ammo, shoot that up and generate my own once fired brass in the process, my observation is that about 50% of my once fired brass will need to be trimmed, I've been doing a lot of trimming! __________________ John

March 22, 2005, 09:02 PM	#9
Desert Dog Senior Member Join Date: September 22, 1999 Location: Deep East Texas Posts: 474	Drill presses make case trimming a snap... The job still sucks though... :barf: __________________ Yes, in fact I do have a 454... in more ways than one. "No provision in our Constitution ought to be dearer to man than that which protects the rights of conscience against the enterprises of the civil authority" - Thomas Jefferson

March 22, 2005, 11:53 PM	#11
G56 Senior Member Join Date: June 10, 2004 Location: Oklahoma Posts: 302	There is a way to take the tedium out of trimming, the only problem is that it's expensive. http://www.giraudtool.com/prod02.htm __________________ John

March 22, 2005, 02:26 PM	#3
CaptainRazor Senior Member Join Date: February 16, 2005 Location: Charleston, WV Posts: 302	Generally, even brand new brass it right at the maximum length. Usually, when I buy new brass, I go ahead and trim it because it's usually to long anyway.

March 22, 2005, 02:29 PM	#4
deerhunter17 Member Join Date: March 18, 2005 Location: North Central Wisconsin Posts: 57	You will just need to get a case trimmer and a Caliper.

March 22, 2005, 02:49 PM	#6
arrggg Member Join Date: December 6, 2004 Posts: 22	ok, thanks for the help

March 22, 2005, 05:12 PM	#7
CaptainRazor Senior Member Join Date: February 16, 2005 Location: Charleston, WV Posts: 302	Just for the record, I really HATE trimming cases.

March 22, 2005, 10:56 PM	#10
DAVID NANCARROW Senior Member Join Date: November 5, 2000 Location: Wyoming Posts: 1,761	I'm not wild about case trimming either, but I do like the Lee zip trim. Resize, chuck the case, insert trimmer, and pull the cord handle. If you are shooting a bolt rifle, you'll find a lot less trimming with neck sizing your cases.

March 23, 2005, 01:58 AM	#12
CaptainRazor Senior Member Join Date: February 16, 2005 Location: Charleston, WV Posts: 302	Ouch! That's a bit pricey. Think I'll just stick with my old Lyman universal, I really don't have to trim much anyway, but it's just so slooooow going. Anyway, while we're on the subject. I've been having some crimp issues with my 45ACP cases. I spot checked some of my empty brass and sure enough, I'm going to have to trim them. Now, on to my little problem, I have some once fired stuff, and I checked some of them, and they are below trim to length. As with some of my other brass, I run across a few that are to short as well. I am certain that they haven't ever been trimmed before. Any of you guys ever run into this before? If so, what did you do?

March 23, 2005, 04:22 PM	#13
Dave R Senior Member Join Date: January 7, 2000 Location: Idaho Posts: 6,073	I have run across this once. The only option is to shoot 'em until thry grow, right? I don't notice any major accuracy changes. I suppose it would affect crimp, if you are crimping that brass. But I don't own any rifle brass I need to crimp. __________________ I am Pro-Rights (on gun issues).

March 23, 2005, 06:05 PM	#14
Nnobby45 Senior Member Join Date: November 20, 2004 Posts: 3,150	Be carefull Brass stretches primarily through the full length sizing process and simply has to be trimmed. Don't like trimming? You have to if you're a handloader. Neck sizing only can prolong the matter, but you'll have to full length size eventually. Bump the case mouths in a sizer, just enough to straighten them out. New cases come dinged up from the factory. New brass doesn't always come from from the factory in uniform lengths. Just trim them all to minimum. Time envolved is a wopping 10 seconds per case after you're set up and running. Make sure you set your trimmer properly. It's really depressing to ruin 50 cases before you realize your mistake! Then champfer and deburr the case mouth. Mandatory. For you new handloaders: Where does the extra brass come from that makes the case neck longer? If you don't know the answer, you need to research it until you understand case resizing, case stretch, and head space. What is an incipient (partial) case head seperation? It's a split (upon firing) at the web of the case because the brass has become thinner during the firing and resizing process. (The crack starts on the inside of the case and you can't see it) Guess where the brass went. Well, it went to the case mouth,that nobody likes to trim, and made it longer or thicker. If you've HAD to trim 4 or 5 times, you might consider that the limit and discard the cases. The brass has simply become too thin near the case head. You can feel the crack inside with a paper clip bent into a hook shape. You should keep a log and know exactly how many times a batch or LOT has been reloaded. When you learn how many times you can trim a case before cracks appear on the inside, then discard them just before you reach that point. When a case is fired, the case expands tight against the chamber walls and forms a seal. Except for the thicker part of the case at the rear. There, it can only stretch backwards until it is stopped by the bolt face. The amount it has to travel to do that is generally referred to as the head space (not the technical definition). Too much headpace can cause a seperation, (it can only stretch so far without splitting), and so can normally safe headspace if the brass has become too thin there, as described above. If the shoulder of the case is set way too far back through improper resizing, then it can result in a catasrophic full case head seperation ALL of the pressure escapes into the action and can blow up the gun and the shooter. The safety vents can't handle that much pressure. NOTE: UNDERSTAND the concept of full length resizing! As in: Just enough for the case to fit your rifle so as to reduce case stretch upon firing. The less serious, but still dangerous, partial head case seperation amounts to a crack all the way through the case where SOME of the pressure escapes into the action, and escapes out the vents on the receiver peppering the shooters face and shooting glasses with powder residue. Can draw blood. Or cause eye damage if shooting glasses aren't worn. Gun damage usually results in a ruined extractor on rifles like the Rem. 700, but usually not more serious than that. Remember that we're dealing, typically, with 50,000 lb. per sq. in. or more of pressure (PSI). It concerns me when shooters jump into hand loading without learning the basics first, and when they take advice from well meaning, but not necessarily knowledgeable, fellow shooters. Many shooters on the board are very knowledgeable, and some aren't. Be careful. Last edited by Nnobby45; March 23, 2005 at 07:36 PM.

March 23, 2005, 06:55 PM	#15
Nnobby45 Senior Member Join Date: November 20, 2004 Posts: 3,150	double post Sorry about the dbl post

March 24, 2005, 09:34 PM	#16
arrggg Member Join Date: December 6, 2004 Posts: 22	well I shot my first reloads today, I shot 2 five shot groups one measured .542" the other .560, these were done with lee collet dies, this was a VAST improvement over factory ammo, these were not the best groups they were the only groups, I am quite pleased, thanks for the help.

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