308 brass is tight on closing bolt

S

Scottish Highlander

New member
Evening all, long time since I have posted on here. I have been reloading quite some time now and was always using once fired Sako brass in my rifle that was fire formed to my rifle. I recently bought 140 Lapua brass once fired from a source. I trimmed all the brass and it had already been necked through a die and tumbled.
I primed and loaded with powder but now that I've done that I went to fire the brass and the bolt is very stiff on closing on some of it. Not all of it!

The brass is the correct length which is 100% definite.
The bullets COAL are all withing parameters with the bullet seated so it is .040 back from the lands. Obviously the only problem left is the shoulder of the brass is hitting the rifling as I shut the bolt which is making it stiff to close.

My question is are these safe to fire and once fired will they fire form to my chamber or will they still be stiff to close. I don't have a full length die but might need to buy one to bump the shoulder back a thou or two so the bolt closes smooth.

What is your technical opinion everyone ?

Thanks all the way from Scotland :)
 
My question is are these safe to fire
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As long as the bolt closes, they will be safe to fire

You need a full length sizer if you want to use brass fired in other rifles.

They won't size themselves smaller by firing in your chamber
 
many years ago a manufacturer of reloading suggested crimping was a bad habit. that was before neck tension, they suggested crimping could reduce bullet hold. Then there is that other problem with crimping, it is possible to buckle the case at the case body/shoulder juncture. When this happens the shooter/reloader finds sizing the case when closing the bolt is difficult.

Then there is the rare possibility the bullets are 8mm.

I would suggest you attempt to chamber the rounds after sizing and before loading.

Then there are chamber gages, there are case length gages. there is no shortages of barrels abound here so more often than not I use a barrel.

F. Guffey

After reading Snyper's reply. Firing ammo that causes difficult bolt closing is a bad habit.

F. Guffey
 
They will still be tight after you fire them. You'll need a FL sizer to bump them back. I FL size only enough so they fit snug in my chambers.
 
I have the same issue with 300 blackout newly formed cases. I ran them thru my resizing die. I hope this will cure my issues. Old brass cycles fine.
 
If you take a load that doesn't fit and remove the bullet then you know the bullet is off the lands when chambered. Measure the OAL to make sure the case length is correct. If the case is still tight then bump with a Full Length seizing Die. When ever you are chambering a load that was fire formed in a other rifle. It is wise to full length resize. After firing in your rifle you can bump or neck size but bumping is best.
 
Any time you use range brass you have to FL size. I FL size everthing because my rifles have such tight chambers I need to and by doing so any of my friends can shoot my ammo.
 
The brass is the correct length which is 100% definite.
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My cases have two lengths, one is measured from the mouth of the case to the head of the case. I call that case length, I use a case trimmer when controlling case length.

I also have another case length, it is measured from the datum/shoulder to the head of the case. I control the length of the case from the datum/shoulder to the case head with a full length sizing die, press and shell holder. I hate it when a case whips my press, it is possible for a case to have more resistance to sizing than my presses can overcome. I do not wait until I have loaded my ammo to determine if the case whipped my press, I measure the gap between the top of the shell holder and bottom of the die to determine the winner, the case or my press.

F. Guffey

The outcome was in doubt, I was sizing cases that I knew nothing about, I was forced to go for my no name lube, the cases began to yield to sizing. Problem, the cases that refused to be sized also had to be hammered into the shell holder.
 
Brass being correct length/neck being correct diameter are totally different from the shoulder being in the right place. ;)

Resize ALL new/old/picked-up brass to fit the particular rifle's headspace you intend to fire it in.
(If you don't know/haven't determined the rifle's relative headspace, then full length resize to start.)
 
Buy a small base resizer. Less monkey business.
Small base resizer will 99% of the time smooth out a cartridge's chambering problem. So long as its brass is within tolerance. (correct length)
 
Highlander,

I couldn't discern from you post whether by "necked through a die" you meant they had been neck sized only or if you meant they had been run through a full-length sizing die. If they were neck sized only, then it's no surprise they don't fit. It just means the other fellow's chamber was either a little longer or a little wider than yours, so the cases were fireformed to a larger size than you chamber.

If they were run through a full length die, then the chances are the die just wasn't set up properly or was set up to just size enough to fit the case back into the original, longer chamber they were fired in. Often, running them through a properly adjusted full length sizing die a second time will bring that cases down another thousandth or two, which can make quite a difference.

The length of a case from head to mouth may be 2.000-2.015 in to meet military 7.62 specifications (for which the outside dimensions of the case are identical to .308 Winchester) and 1.995-2.015 in to comply with U.S. SAAMI standard. That length is not very critical, and, indeed, some gas gun competitors used to trim to 1.955 in just to avoid having to trim again during the useful case life in a gas gun (usually about 5 load cycles, counting the original load, if they got the case as loaded ammunition).

AFAIK, the CIP uses the old military method of determining case fit into the chamber. This is by measuring from the head to the sidewall and shoulder intersect. Their drawings offer four measurements you can check, which are P1 and P2 for diameter and L1 and L2 for length on their .308 Winchester drawing, allowing a tolerance of minus 0.2 mm (-0.0079 in). SAAMI uses a reference diameter on the neck that is shared by both the cartridge case and the chamber to be measured from the head to or the breech face, respectively. SAAMI allows a tolerance of minus 0.0070 in (-0.18 mm), as you can see in their drawing. I put in my shoulder datum illustration below so you can see how that works.

308Headspace_zps92b24532.jpg
 
(If you don't know/haven't determined the rifle's relative headspace, then full length resize to start.)
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Or do as I do, I look for cases that have been fired in long trashy old chambers, that would be a proverbial case "a case that was fired in a chamber you do not have".

HOW DO I DETEERMINE HOW TRASH THE CHAMBER WAS? I measure the length of the case from the shoulder to the head of the case, I want cases that are longer from the shoulder to the head of the case than it available from case manufacturers. When I find the trashy old cases I sort/separate them. When I want to know the length of a chamber I start sizing the cases and checking the length from the shoulder to the head of the case. Once I get to standard length +.010 I attempt to chamber the case. If the case allows the bolt to close I have a trashy old chamber. If the bolt does not close I can measure the length of the chamber with the +.010 case (.001" longer than a no go-gage gage) to determine the length of the chamber in thousandths ot I can continue sizing the case until it chambers.

Or as mehavey said: " (If you don't know/haven't determined the rifle's relative headspace, then full length resize to start.) I have no clue why a reloader would waste a perfectly good case that has been fired in a trashy old chamber by full length sizing it back to minimum length. To me it seems the reloader would be passing up every opportunity to become a reloader.

Again, I have one chamber that is .016" + over the length of a minimum length/full length sized case. that is .011" longer than a go-gage length chamber. Manufacturers do not make cases for reloaders that have threads on their presses and dies so I form 280 Remington cases to 30/06 cases. When forming I add .014" to the length of the case from the datum to the head of the case. I use feeler gages when adjusting the die off the shell holder.

F. Guffey
 
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