The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools
Old January 7, 2013, 02:55 PM   #1
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
Noob question re reloading 308

Hello all!

I am breaking into the reloading game, and i can't tell if it is my rank noob-ness or another issue that causes this problem, but I'd like to throw it out there and get some perspective...please?

I had a windfall of approximately 5000 LC match 308 brass. I am slowly tumbling and de-priming the brass using walnut media in a cabelas tumbler and using the Lee Pacesetter Die set in the Lee Breech Lock Hand Press. I have deprimed approximately 1000 of my brass thusfar. (a good workout if anyone's interested).***Also, I add a capful of meguiar's scratch doctor to the mix for a better shine on the brass...

I am wondering though, what is a permissible minimum overall brass length for 308 if I intend to run this ammo as plinker ammo through a semi-auto 308 (SA-58)?

thanks in advance for the input.
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 7, 2013, 04:31 PM   #2
Okcafe86
Senior Member
 
Join Date: October 15, 2012
Posts: 102
Google saami. I always load to saami specs, which happens to be the same as what reloading manuals call for. In the case of win.308, min case length is 1.995". Someone please correct me if I'm wrong.
__________________
PRIDE RUNS DEEP
US NAVY SILENT SERVICE
MM2/SS
A-GANG/LOWER LEVEL MAFIA
Okcafe86 is offline  
Old January 7, 2013, 05:01 PM   #3
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 10,412
Welcome to the forum.

The SAAMI standard is 1.995" to 2.015". The military standard is 2.000" to 2.015". However, some service rifle match shooters used to trim down to below either number to around 1.980". This was done with the idea they would have to retire the brass before they had to trim it again. In self-loaders brass life is not usually high, due to the hard extraction, 4 to 6 reloads being typical. At an average of 0.005" growth per load cycle, that works out about right. Also, if you have a manual trimmer only, while this over-trimming practice doesn't save you any actual cutting time, it does save you having to remount the case for trimming more than once.

The main thing is that whatever trim length you chose, you check to be sure it doesn't adversely affect accuracy in your gun. With some short bearing surface bullets like the 155 grain Sierra Palma bullet, that over-trimming practice could force you to seat deeper than your gun likes best, just to help the case hang onto the bullet. Or, you could just stick with one of the published limits, above.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Benefactor Member

Last edited by Unclenick; January 7, 2013 at 05:25 PM.
Unclenick is offline  
Old January 7, 2013, 05:53 PM   #4
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
Thank you both.

I bought a digital micrometer today to do precise measurements, here is hoping I fall within those saami specs.

I only intend to be within spec, not do anything exotic.b What I did with approximately 100 cases is deburr and chamber with an RCBS hand tool, and I want to make sure I was not too zealous and make my shells fall out of spec.

I was also concerned with pressure problems (if any) that might show up if the cases are perhaps a hundredth out of spec (too short)?

Thanks again all!


....andI of course acknowledge my noob-ness in regard to not testing case length prior to deburring and chamfering.

Stupid, I know.


Unclenick---(and any others)

to what degree should my brass be uniform for purposes of plinking reloading?

Saami specs most permissible for pressure/safety purposes?

Also, what toll would you recommedn for trimming. I am looking for low budget/accurate. (I typically want my cake and to eat it too).

thanks.
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."

Last edited by Unclenick; January 8, 2013 at 09:42 AM.
Gunnutfn49 is offline  
Old January 7, 2013, 06:08 PM   #5
89blazin
Senior Member
 
Join Date: March 13, 2009
Posts: 107
Check out this article on reloading .308 / 7.62x51

http://www.m14.ca/reloading/14_loading.pdf
89blazin is offline  
Old January 7, 2013, 06:09 PM   #6
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
will do 89blazin.

appreciate the input.
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 8, 2013, 11:39 AM   #7
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 10,412
Gunnutfn49,

The distance between the bullet base and the bottom of the case affects the volume of the powder starts burning in. If you shorten the case necks, but keep the finished cartridges the same overall length, the pressure won't be affected significantly by the shortened neck. The only reason to keep trimming exactly within the SAAMI standard is if you are crimping the cases, in which case the accuracy of the length is for repeatability of the crimp force is important.

I don't expect your LC cases to have enough volume difference among them to matter for your purposes. Assuming the exterior dimensions were identical (usually close enough to true if the headstamps match), the internal capacity of the cases may be approximated by weight. Figure that it takes about 1.5 grains different in brass case weight for the volume change inside the case to equal the influence of 0.1 grain change in powder charge weight. The exact number will vary some with the powder and bullet choices, but that's a pretty good generalization.

A reasonable practice for accuracy loads or for loads that run right up at maximum pressure is to segregate cases with the same headstamp into groups that span no more than three grains weight difference. That makes the influence of their difference no greater than the limit imposed by the precision of standard powder scales (±0.1 grains). For plinking loads, except for obvious damage, if your headstamps are the same, you don't need to weigh cases. For mixed brass for plinking, though, you can find up to around 30 grains difference in case weight between brands. That's enough to matter. It's effect will be about like a span of two grains of powder charge difference. I would sort mixed headstamp cases into groups with not more than 10 grain spans, and not use them for loads all the way up at maximum pressure.

As to the length of the shoulder from the case head, for plinking loads just use a case gage like the Wilson type, and if the case is within its limits, you'll be fine. Setting a shoulder back so much that it's too short in a gage can allow the cartridge to headspace on the extractor rather than the shoulder. That reduces accuracy and adds to stretching that shortens case life. For accuracy loads in a self-loader you usually want to determine how long the cases come out of the chamber then adjust the seating die to set the shoulder back 0.002"-0.003".

But as to peak pressure, in any cartridge with a pressure peak over around 30,000 psi, the resizing differences among otherwise identical cases make no practical difference. The peak pressure is determined by the volume of the case after it expands to fill the chamber, so the size of your chamber determines that.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Benefactor Member
Unclenick is offline  
Old January 8, 2013, 07:22 PM   #8
rduckwor
Senior Member
 
Join Date: June 26, 2008
Location: L.A. - Lower Alabama
Posts: 359
Maybe I missed it, but have you full length sized any of this brass yet? You mentioned depriming, but did not mention sizing. No point in trimming until you size.

Good luck,
__________________
RMD
rduckwor is offline  
Old January 8, 2013, 07:41 PM   #9
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
Unclenick -thank you. I chamfered and deburred prior to buying a caliper. Clearly this was a case of putting the cart before the horse.

thankfully, most (approx 85% of the 100 i C'd and D'd) are still within the Saami specs.

I wanted to post another question, with some photos to see what other wisdom I could get out of the forum. I want to make sure that I have seated my bullets properly.

the first ten of 15 were too long or exhibited the following problem (see attachment).

the last 5 no longer exhibited the problem of the "bubbled" shoulder, and all appeared to be in spec per my speer manual and the saami specs.

I fixed this issue through trial and error with the fitment of my lee pacesetter bullet seating die.

does anyone have any other tips or techniques that i should be aware of to avoid wasting another 10 brass? or is this the attrition rate i should expect until i get a better feel for the die/brass relationship?

thanks in advance!
Attached Images
File Type: jpg 308mistake2.jpg (233.6 KB, 32 views)
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 8, 2013, 07:43 PM   #10
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
rduckwor- all the brass mentioned above has been full length resized as I am using the lee pacesetter 3 die set. does that change your answer?
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 8, 2013, 07:47 PM   #11
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
This is an example of the final five (sans powder and sans primer for chamber testing).
Attached Images
File Type: jpg 308successmaybe.jpg (243.5 KB, 31 views)
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 8, 2013, 09:39 PM   #12
dmazur
Senior Member
 
Join Date: July 5, 2007
Location: Pacific NW
Posts: 1,310
Headspace concerns have already been mentioned, but as you are new to this I thought I would bring it up as a separate reply.

You should gauge your resized brass to check the adjustment of your resizing die before doing all 5000 too short, which will set up an excess headspace condition.

Excess headspace caused by misadjustment of the die is sometimes called "induced excess headspace" because the dimensions of your chamber haven't changed. Worn bolt lugs create a true excess headspace condition, for which the solution is usually a new barrel.

It is also possible that the cases haven't been resized enough to chamber easily, and this can be dangerous in many semi-autos as it can lead to a slamfire.

Quote:
all appeared to be in spec per my speer manual and the saami specs
I see you are trying "dummy rounds" for chamber fit testing, and that is a good idea.

However, without a gauge, you can't measure headspace. If you are resizing brass fired in a different gun, it could already be the correct length and not need to have the shoulder pushed back a couple thousandths.

The only thing I can offer, other than getting a headspace gauge, is to try for uniformity in all parts of your process. If you have inconsistency, you will end up chasing yourself.

In theory, once you have each part of the reloading process figured out, making 1000 rounds vs. making 10 rounds is just a matter of patience.
__________________
.30-06 Springfield: 100 yrs + and still going strong

Last edited by dmazur; January 8, 2013 at 09:48 PM. Reason: added comments about headspace gauge
dmazur is offline  
Old January 8, 2013, 11:03 PM   #13
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
dmazur-

If I am full length resizing, and I've checked probably 200 of the 1000, and all seem to be within saami spec (based on rookie observations with my calipers) should I be worried about the concerns you raise?

I'll be ordering a set of headspace gauges tonight.

Thank you for the kindly input!
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 9, 2013, 12:08 AM   #14
dmazur
Senior Member
 
Join Date: July 5, 2007
Location: Pacific NW
Posts: 1,310
This is an example of a cartridge headspace gauge (Midway calls it a case length / headspace gauge)

http://www.midwayusa.com/product/880...308-winchester

I see they're out of stock. LE Wilson may have them, and they sell directly, I believe (not just to distributors). Dillon may have them in stock, and their pattern is similar to the Wilson. LE Wilson's web site has a pdf manual for use of their gauges. The instructions are generally applicable to any gauge of this pattern, regardless of who makes it.

These gauges have a hi/lo step on the bottom (for cartridge headspace) and a hi/lo step on the top (for case length). Both are important for safe reloading. Only one can be measured with calipers, and it isn't cartridge headspace.

There are far more complex tools for measuring cartridge headspace, but the Wilson pattern is a good place to start.

Quote:
based on rookie observations with my calipers
Well, the problem is that cartridge headspace is the dimension from the head of the case to an established "datum" midway up the shoulder. It isn't case length, which is measured to the mouth. The difference between minimum and maximum is only 0.006" or so, impossible to determine by visual examination, or by estimating the position of one jaw of a caliper held to one side.

Clymer is one manufacturer of a true headspace gauge set, used by a gunsmith to finish ream a chamber when fitting a new barrel. It will be of absolutely no use in setting up a resizing die, as it is measuring the chamber, not the case.

You can download Clymer's catalog if you want to read up on chamber headspace gauges -

http://clymertool.com/catalogue/index.html

So, if you are ordering a headspace gauge set, you may be ordering the wong tools. The Wilson gauge is one per caliber, not a set. And they cost $35 or so. The chamber headspace gauges are going to be $120 for a full set of 3 (GO, NOGO and FIELD).
__________________
.30-06 Springfield: 100 yrs + and still going strong
dmazur is offline  
Old January 9, 2013, 12:47 PM   #15
medalguy
Senior Member
 
Join Date: August 31, 2009
Location: New Mexico
Posts: 1,020
Since you have match brass, it's an excellent bet they were not fired in a machine gun, so I'd suggest checking the case length before you trim. It's possible they may be within specs without any trimming at all. Just a suggestion. (BTW I hate trimming, can you tell?)

If you do trim, I'd recommend 1.990 length. I trim to this length, reload 5 times, and pitch the brass. Never have to trim it again. I shoot it in an M1A, an M14, or a FAL so I use it pretty hard.
medalguy is offline  
Old January 9, 2013, 03:07 PM   #16
Bart B.
Senior Member
 
Join Date: February 15, 2009
Posts: 5,244
I think one needs only one gauge for checking bottleneck cases for one important size issue. They'll also need one good caliper to measure those cases for all the other size issues. These two measuring tools are plenty.

Use the caliper (digital or analog) to measure case diameters and length. Can also be used to measure neck wall thickness pretty accurate. A 4" one is good enough unless you need a longer one.

Use a case headspace gauge (RCBS Precision Mic or the Hornady one) to measure where the shoulder is on cases. Measure the case headspace (head to shoulder) dimension on a fired case, then set the full length sizing die in the press to set that shoulder back 2 thousandths after it's sized.

That's all folks.
__________________
US Navy Distinguished Marksman Badge 153
Former US Navy & Palma Rifle Team Member
NRA High Power Master & Long Range High Master
NRA Smallbore Prone Master
Bart B. is offline  
Old January 10, 2013, 10:19 PM   #17
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
All,

Wife broke her ankle on the date of my last post, havent ordered any gauges yet, as ive been playing mr. Mom to my wife and two year old son.

Thanks all for the input, ill read, reread and then decide on proper gauges. Thanks again for the care taken in all responses.
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 10, 2013, 10:35 PM   #18
jimbob86
Senior Member
 
Join Date: October 4, 2007
Location: All the way to NEBRASKA
Posts: 7,038
Hope the wife gets better .......

That Mr. Mom thing isn't bad, once you get things running the way you want them- I've been doing it 8 years for 5 kids!

Yeah, I vacuum .... with my Shop Vac.....
__________________
TheGolden Rule of Tool Use: "If you don't know what you are doing, DON'T."

http://nefirearm.com/
jimbob86 is offline  
Old January 10, 2013, 11:04 PM   #19
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
Shop vac! I love it!
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 10, 2013, 11:10 PM   #20
jimbob86
Senior Member
 
Join Date: October 4, 2007
Location: All the way to NEBRASKA
Posts: 7,038
We killed 2 conventional vacs before i just said what the hell- I'll just bring in my 20 gallon Sears Shop Vac .... been going strong for years now ..... and will suck up stuff like spent primers and BB's that are bad juj-ju for regualr house vacuum cleaners..... HEPA filter bags are cheaper for them too.
__________________
TheGolden Rule of Tool Use: "If you don't know what you are doing, DON'T."

http://nefirearm.com/
jimbob86 is offline  
Old January 10, 2013, 11:37 PM   #21
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
Seems like a darn good solution considering the problem.

My wife sucked up legos with a british (read "expensive") vacuum, and it took an hour to strip it down and get the stupid things out.

Son has even more legos and i can now field strip the vacuum in less than five minutes. Never thought that would be a point of pride, but hey....kids man.....
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 11, 2013, 10:45 AM   #22
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 10,412
Gunnutfun49,

Your buckled case shoulder was likely due to the seater die body being set too low and the crimp shoulder pushing down too hard on the case neck. The Lee help video for this is here. If you don't want to use a crimp (I don't usually), just don't follow the last instruction to turn the die in a half turn, instead turning it out a half turn, then checking the seating depth adjustment once more.

To gauge case shoulder setback for sizing die setup, you just need to know where the shoulder is on a fired case and that you set it back below that level. -0.001" below fired case for bolt guns, and -0.002–0.003" for gas guns. You can check this with a caliper and a spacer whose through-hole is about the size of the middle of the shoulder. Below I've used a hardware store bearing journal bushing instead of a spacer, because it was convenient, but spacers work, too. In the photo the .30-06 case is 0.003" bigger than a headspace gauge I had zeroed it on previously, but just zero on a fired case and see that you get the -0.00# number you want.

__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Benefactor Member
Unclenick is offline  
Old January 20, 2013, 06:41 PM   #23
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
your name isn't, uncle "saint" nick is it? your help is great. Glad you are a part of the forum

Gunnutfn49
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Old January 23, 2013, 04:06 PM   #24
Gunnutfn49
Member
 
Join Date: January 3, 2013
Location: PR of Kalifornia
Posts: 77
Purchased a set of Hornady Headspace gauges over the weekend. Looking forward to using them perhaps this weekend.
__________________
"...and which is worst of all, continual fear and danger of violent death, and the life of man, solitary, poor, nasty, brutish, and short."-Thomas Hobbes, Leviathan

...What he meant to add was, "unless, of course, all responsible citizens are armed to the teeth."
Gunnutfn49 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 09:39 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.12269 seconds with 8 queries