Forming .308 Brass

[hook69]

I want to form fire new brass to the chamber of my .308 rifle before neck sizing and loading hunting rounds. What would be an inexpensive and effective way of accomplishing this?

[pathdoc]

Load a minimum charge of the cheapest powder available on top of a cheap bullet with a low-cost primer. Go to the nearest range. Set up a target at a suitable distance. Fire.

Lather, rinse, repeat.

[hook69]

any way to avoid wasting a lead bullet?

[RC20]

No, you need pressure to fire form, no bullet, no pressure.

On the other hand there is not reason you can't just re-size to a safe spec, fire form it, measure it and then adjust your dies to the minimum setback for your chamber.

There is no downside and the upside is you get what you want.

I shoot my stuff in 5 different rifles so it all gets re-sized to safe specs as its not worth trying to track brass to a given gun.

One gun and you are home free so load er up, do a bit of power variation to work your way toward the accurate load you want, sight in the gun to point of aim you will be at and you get all that done for free.

[Damon555]

Just don't bother fire forming....Use the brass as intended right off the bat. Then after the initial firing you can start neck sizing.

Don't get carried away with whole reloading process. You'll likely notice very little difference in accuracy between the unfired rounds and your fire formed rounds.

[4runnerman]

Wait a minute here- You do not need to waste a bullet to fire form. Depending on your powder ( pistol works great ) Roughly 5 gns pistol powder,Cream of Wheat and toilet paper to keep in it. Fire at range and your brass is fire formed. No need to waste bullets and it creates more than enough pressure to fire form.

Now to agree with others here-Fired formed brass is no more accurate than full length sized brass. Many tests have been done to prove that. In a match grade set up-- Maybe, In a stock rifle - not at all.

[Bart B.]

Most folks will be hard pressed to tell the accuracy difference between new cases and once fired ones resized any way in commercial rifles.

And I've always got better accuracy with new cases compared to neck sized fired ones in both commercial and service rifle chambers as well as SAAMI spec ones in match rifles.

Use max loads to fire form cases. Reduced loads too often don't expand the case enough to be safely neck sized anyway. They end up too short from head to shoulder and that leads to incipient case head seperation.

I highly recommend new or full length sized fired cases for reliable loading and unloading in hunting rifles. Most benchresters switched to minamal full length sizing a few years ago.

[4runnerman]

Bart- Are you sure on the -Not doing the neck?. I know 3 or 4 people that do it with just like 5 gns pistol powder. One of them is doing it to form AI cases and has no issues that he tells s any how.

[Metal god]

Although I've not been loading long I agree with the others that say , just load them up with the charge and bullet you intend to use . Do the whole UBER accurate thing next time around . Your not likely going to notice a difference . The only real reason I only bump my shoulders back .001 or so is to get more reloads from them . If these are hunting loads . Your not likely shooting 100 of them every range trip and need the extra life .

I'm not sure if others do this but I bump my shoulders back .002 to .003 on my hunting loads to insure they cycle in the field .

[Bart B.]

4runner, whatcha mean by "Not doing the neck"...?

[4runnerman]

Bart-Your last post-3rd paragraph?. I guess I dont know what you mean-Sorry

[Reloader2]

Originally Posted by Metal god

Although I've not been loading long I agree with the others that say , just load them up with the charge and bullet you intend to use . Do the whole UBER accurate thing next time around . Your not likely going to notice a difference . The only real reason I only bump my shoulders back .001 or so is to get more reloads from them . If these are hunting loads . Your not likely shooting 100 of them every range trip and need the extra life .



I'm not sure if others do this but I bump my shoulders back .002 to .003 on my hunting loads to insure they cycle in the field .

I agree with most of this. I don't worry about bumping the shoulders on a bolt action rifle, however as I try them at home before headings out into the field.

[Bart B.]

4runnerman, about this:

Use max loads to fire form cases. Reduced loads too often don't expand the case enough to be safely neck sized anyway. They end up too short from head to shoulder and that leads to incipient case head seperation.

And what I meant.... Too short from head to shoulder means the shoulder's set back a few thousandths and the case doesn't expand enough to stretch its back end all the way to the bolt face. In rifles whose chamber's are at the maximum headspace, such cases may allow enough head clearance (space between the bolt face and case head) that more stretching starts cracking the case about 1/4" forward of the case head.

How much a case shoulder gets set back from firing pin impact can be measured with a gauge such as the RCBS Precision Mic or Hornady LNL gauges with a caliper. Or use a nylon spacer half an inch long with a 3/8ths inch inside diameter on the case shoulder then measure the distance from case head to the far side of the spacer with calipers. Compare the before and after firing with a primed .308 Win case in your rifle's chamber. Nickel plated case shoulders get set back a lot more than plain brass ones. How much depends on firing pin protrusion, spring strength and the pin's tip shape. It happens.

When there's too much head clearance for a given cartridge that headspaces on its shoulder, head separation is common when setting dies up according to their instructions. Use a good tool to measure your case headspace before and after sizing to see what's happening. Fired bottleneck cases should not have their shoulders set back more than .003 inch else there'll be problems.

Reloader2.... While some folks don't think setting shoulders back (i.e. they only neck size) is important, it is if best accuracy and firearm operation is important. Especially with factory rifles whose bolt faces are not squared up with the receiver. When the case shoulder gets far enough away from the case head from a few firings, the case will bind the bolt when it's closed. A lot of folks think this is a good idea to have a slight amount of binding when closing the bolt on bottleneck ammo. With the typical out of square bolt faces making fired case heads also out of square, that tends to put the initial force of the case head off center on the bolt face making the barreled action whip differently and cause the bullet to leave the muzzle at some tiny angle not desired. And the bolt head doesn't close in the exact same place each time, either. A 1 MOA change in bullet impact is not unusual. So, resize bottleneck fired cases enough to keep that shoulder in the same place and have a couple thousandths head clearance from the bolt fact to the cartridge when its chambered. Best accuracy and reliably chambering/extracting cases happens when this is done. Most benchresters finally figured this out a few years ago and started full length sizing their fired cases reducing body diameters and setting back shoulders about .001" or so.

[F. Guffey]

I want to form fire new brass to the chamber of my .308 rifle before neck sizing and loading hunting rounds.

Hook69, I chamber a round, pull the trigger and then eject a once fired case, I do not need to add the title of ‘fire former’ to my resume. Before I pull the trigger on a minimum length/full length sized case I measure the length of the case from the shoulder to the head of the case. No one does that, but me. I verify the case is minimum length/full length sized, after firing the case I measure the length of the once fired case from the shoulder to the case head, this means nothing to anyone, but me. I want to know the difference in length between the chamber from the shoulder to the bolt face and the length of the case from the shoulder to the case head. I want to know the effect the chamber has on a new, factor minimum length sized case when fired.

The reason know to no one is why. Why would I want to know the difference in the two lengths? I ask questions like: “How do you do that?” “How would you check that?” Before I can get an answer members of forums turn into Incognito personalities.

I want to know: STRETCH, it is assumed cases stretch, as Bart B. starts with ‘The firing pin strikes the primer, then the complete package including the case, powder and bullet takes off in an attempt to out run the firing pin etc.. Step sequence, I insist he is leaving out a couple of steps, I insist he is omitting a factor or two. I have scribed cases before firing at the shoulder/case body juncture, strange to everyone but me, the scribed line at the shoulder/case body juncture did not move, and I ask “What does that prove?”

Add to resume? I am a case former, I form cases before firing, I form 308 W cases from 30/06 cases.

http://www.saami.org/PubResources/CC...Winchester.pdf

http://www.saami.org/PubResources/CC...pringfield.pdf

The difference in length from the shoulder of the case to the case head for the .308W is 1.559, the 30/06 length from the shoulder case body juncture to the case head is 1.948. To form a 30/06 down to 308W the new shoulder is formed .389” further back. The difficult part to understand the new shoulder is not the original shoulder that has been moved back, the formed shoulder for the 308W is a new shoulder and the old shoulder has been erased and becomes part of the shoulder and neck.

Fire forming, it is assumed all the stretch is between the case head and case body, when I form first and fire there is no stretch between the case head and case body.

Then there are the folks, I do not know who you are so I suggest you ask Bart B.. like “Bart B., am I a ‘folks?’. Some could assume I form all of my cases, the answer is no, if I want to measure a chamber for length I form a case, it is not necessary to start over everyday. I can form a case to determine the length of the chamber then use that case to transfer that dimension to a comparator, sizing die, I do not mind going to the range to fire cases, I do not find it necessary to go to the range to fire form because I form first then fore.

Then there is fire forming, not the topic of the OP question. I have wildcat type chambers, it is necessary to form those cases and then fire to finish. Fire forming finishes the forming process, after firing the case to form the shoulder and case body the case becomes a once fired case.

F. Guffey

[Bart B.]

To anyone who thinks that when the firing pin strikes the primer, then the complete package including the case, powder and bullet takes off in an attempt to out run the firing pin doesn't happen, strip the extractor and inline ejector from the bolt of an action, cock the firing pin, put the action front up, lay a primed case on the bolt face then pull the trigger. That primed case will jump up several inches out running the firing pin.

Same thing happens in the chamber with a loaded round except it's stopped by the case shoulder slamming into the chamber shoulder which holds the case in place while the firing pin dents the primer enough to compress then detonate the priming compound. When this happens, sometimes the case shoulder's moved back a few thousandths so there's more head clearance from bolt fact to case head that there would be if the firing pin had not smacked the primer.

How much primed case shoulders are set back from firing pin impact can easily be measured with case headspace gauges before and after popping that primer in a chamber.

Guffey, if you challenge this fact, you've got a lot to learn. Period!!!!!!!!!!!

[F. Guffey]

Most benchresters finally figured this out a few years ago and started full length sizing their fired cases reducing body diameters and setting back shoulders about .001" or so.

Bart B,. is that the best you can do, I can imagine there are 'folks' out there, or here that want to know what the difference in length is between the chamber from the shoulder to the bolt face and the case from the shoulder to the case head before and after firing. We should understand the difference between off the shelf rifles and bench rester rifles is more than whistles and bells.

Then? there are match chambers, I have bolts, I quit taking them to gun shows, the best I could get was "Hatcher said etc..".

F. Guffey

[F. Guffey]

I remember Mr. Clark used Velcro to center a 308 W case? in a magnum chamber, he pulled the trigger and did not get a dent in the primer and I did not say anything, I got the feeling he thought I was pushing him, he did not ask me how I would conduct the same test. And, that is OK also.

And again, I ask, have you ever scribed a case at the shoulder/case body juncture before firing, I have, the scribe line was .127" behind the new shoulder/case body juncture. I know, you think I am building boobie traps, not necessary, boobies are too easy to catch.

For the folks to think about, if the firing pin drove the total weight of the bullet, case and powder to the front of the chamber causing the shoulder of the case to smack into the shoulder of the chamber the case would have expanded and then locked onto the chamber, and then! pressure inside of the case would have pushed the case head back into the bolt face.

Folks, think. had the shoulder of my case been driven forward to the shoulder of the chamber .127" the case head would have SEPERATED, because we all know the case head can not stretch .127" between the case body and case head.

Folks that are friends have had problems with case head separation when forming wildcats cases for wildcat chambers. One instance, 4 cases out of 10 had case head separation. I asked: What receiver? He informs me what receivers he used. I informed him I could have fixed the problem at his shop before he left for the range, I could have tested the rifle to determine if it could happen before he left the shop, I informed him I could have met him at the range and corrected the problem long enough for him to fire form his cases. He wanted to know why I did not have those problems, simple answer, I do not choose to use the same receivers he used or I form first then fire.

Because I am the fan of cutting down on all that case travel.

F. Guffey

[Bart B.]

For the folks to think about, if the firing pin drove the total weight of the bullet, case and powder to the front of the chamber causing the shoulder of the case to smack into the shoulder of the chamber the case would have expanded and then locked onto the chamber, and then! pressure inside of the case would have pushed the case head back into the bolt face.

That typicaly happens every time a bottleneck case headspacing on its shoulder fires. Most of the time, case travel's only a few thousandths inch before it slams into the chamber shoulder. The distance is equal to head clearance if the case head's against the bolt face when the firing pin strikes it. If the case shoulder's already pushed against the chamber shoulder from in-line ejector force, then the travel's zero before the case shoulder sets back a little bit as the primer fires.

Kapeesh?

[F. Guffey]

Bart B., do you own a press?

I will assume you have never scribed a case, not surprising, there are writers that have written volumes, some are quoted and considered world shakers in the field of firearms, chambers and head space, one set up an experiment, he picked the wrong rifle or someone handed him the other rifle. He could have saved a lot of confusion had he scribed the case.

he picked the wrong rifle

Allow me to clarify to the folks. Same brand, make and model, and the part where I told my friend I could check the rifle to determine if it had the propensity to experience case head separation when fire forming wildcat cases. Meaning with the same make and model it is possible to fire fiorn cases without case head separation even though all were designed to experience case head separation with excessively long chambers. And they had no clue because they never scribed the case at the case body/shoulder juncture.

F. Guffey

and now typically? Then the primer is added to the sequence of events.

[Bart B.]

No, Guffey, I don't own a press. Never took the time to buy nor learn how to use one.

I resize cleaned and lubed fired cases by pushing them into dies with the heel of my hand while the other hand holds the die. Then I bite my teeth in the extractor groove, grip the die with both hands then pull it off the case.

Are you finished with your dumb questions, now? If not, I've got more answers of the same ilk.

[Sure Shot Mc Gee]

Fire forming brass to chamber size. Should to be done with a normal suggested powder charge and bullet if you want to do it right. Lesser charge. 5-6 grs. and some cream of wheat. You take a chance you might not get the result's you want. May even call for more than one attempt to get the job done. Frankly I don't know why the need to fire form new brass. Unless it has something to do with case tension memory or oversize chamber measurements. I'm at a lost on this one OP.

[F. Guffey]

any way to avoid wasting a lead bullet?

Yes there is, no powder, bullet, I can form cases hydraulically, in less than 1 hour most members on reloading forums can Google and do in well enough to dominate the topic, many years ago I removed Berdan primers with the same messy method, difference, the hole in the shell holder. I want the primer supported in JIC, as in just in t case I have to hit it twice.

F. Guffey

[Bart B.]

What's the objective in fire forming before neck sizing?

[Metal god]

I resize cleaned and lubed fired cases by pushing them into dies with the heel of my hand while the other hand holds the die. Then I bite my teeth in the extractor groove, grip the die with both hands then pull it off the case.

See , Now thats funny stuff right there

[F. Guffey]

What's the objective in fire forming before neck sizing?

“Frankly I don't know why the need to fire form new brass. Unless it has something to do with case tension memory or oversize chamber measurements. I'm at a lost on this one OP”

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I chamber a new loaded round, I then pull the trigger, after pulling the trigger I eject a once fired case, everyone else ejects a fire formed case. If I was going to fire form cases I would measure the new, unfired, factory case first from the shoulder to the case head.

Why/rational? I want to know how much the case traveled from the case head to the shoulder or from the shoulder back to the case head. If I do not measure the length of the new case from the shoulder to the case head I do not know how much the case traveled. And I would not know the length of a minimum length/full length sized case. It helps to understand the concept of zero when using a comparator. I have minimum length/full length sized cases, I have go-gage length chambers, I have no go-gage length gages, I have field reject length gages and all the gages that fill in between minimum length to field reject length in thousandths. I know, that means nothing to a reloader, but when I chamber a minimum length/full length sized case I know what the length of the once fired case will be before measuring it for length.

What's the objective in fire forming before neck sizing?

I form first, when I form cases part of the neck becomes part of the shoulder, part of the shoulder becomes part of the case body or part of the shoulder becomes part of the neck and the shoulder becomes part of the case body, strange thing about forming, the shoulder of the parent case does not move, it is erased, the new shoulder is formed. Reloaders insist they move the shoulder back by bumping, and I ask, ‘when does bumping end and forming begins?’ .

There are not many dies I do not have, the dies I use are the dies that are integral, one piece, I was ask to make dies that were not, I had no interest.

F. Guffey


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