Brass stretching

[ole farmerbuck]

About how much should my 22-250 brass stretch when i full length resize. I measured some tonight and some 'grew' as much as .010. I used one shot inside the case mouth on some and powdered graphite on others and they all stretched when pulling the expander out. Is this normal? I will only neck size after i fire these cases in my gun.

 

[Doug b]

Yep the 250 is a high performance round and it will stretch a lot, your on the right track with neck sizing after fire forming to your chamber.Keep in mind you will have to bump the shoulder back when you start to get a lot of resistance to locking the bolt.

You mention stretch when you pulled the expander back through the neck.If this required a lot of effort you may have pulled the shoulder out some.Check by seeing if the empty case chambers in your rifle before you load it.Generally a nylon bore brush applied to the inside case neck will nock out the carbon residue and lube may not be necessary.

 

[ole farmerbuck]

Ok thanks Doug. I'll try a brush next time. I have a small plastic container of lube i got from Sinclair. It has real small grainular stuff with what looks like powdered graphite mixed in. When i only neck size with the Redding die, its not near as hard to get the expander out as it is when i full length size with the Hornady die.

 

[jbkebert]

Yes sir I have cases that are stretching up to .012 after resizing. Even my .308 stretches .009 after resizing. You may find that you will only get 5 or maybe 6 loadings from your 250 brass. It will greatly depend on the brand of brass that you are using. I am finding that Laupua and Hornady brass will stretch a little less than say Winchester or Remington. I beleive the premium brass is a little harder in composition than the midline stuff. Just take your time and trim it all back and start the process.
Good luck

 

[243winxb]

When full length resizing (FLRS), all brass gets longer, this is normal. If you FLRS without the expander button being used and take a measurement of the cartridge overall length what do you get? When the expander is used what does it measure? Is this where your getting the difference of .010"?Always us a nylon brush with lube (rcbs) on it to condition the inside of the case neck.

 

[ole farmerbuck]

I checked one before resizing and then after. Then i took the expander out and resized to see if it would shorten it any. It didnt. So evidently the shoulder isnt stretched enough to hit the die?

 

[rcmodel]

The 22-250 is one of the only calibers I have reloaded that required neck reaming eventually.

There is a lot of brass flow going on there with max loads.

rc

 

[ole farmerbuck]

I resized some .223 brass lastnight. They didnt stretch nearly as much and the expander pulled out much nicer. Why is that.

How do i go about neck reaming? New to me. Thanks

 

[243winxb]

I resized some .223 brass lastnight. They didnt stretch nearly as much and the expander pulled out much nicer. Why is that.

They didn't stretch as much because your rifles chamber is smaller, less sizing. And/or there is less metal in the neck area, thin neck wall diameter.

How do i go about neck reaming? New to me.

First you have to know if an adjustment to the neck is needed. Take the fired cases, see if a bullet of the correct diameter for the caliber will drop freely into the case. If it does, NO reaming or outside neck turning is needed. If the bullet does NOT fall into the cases that were fired using maximum loads(light loads may not expand the neck), then i would neck turn the brasss. I use a Lyman. First FLRS the brass the normal way. Then use the Lyman neck turning tool that fits on the Lyman case trimmer. When you FLRS, the excess metal was moved to the outside of the case neck. This is what you will trim off with a very light cut going all the way to the shoulder.

 

[jbkebert]

A couple things will influence how much a case stretches. A .223 has a diffrent angled shoulder than a .308. That will have a little effect on stretching. The amount of times the case has been fired will have a little effect. Excessive head space will have a little effect. A enlarged chamber will effect this as well.

Case in point my .308 savage 12bvss a once fired case on average stretches .006 with match brass from hornady. I get around .007 with remington brass. My T/C Encore in .308 will strech .009 to .010 with match brass and up to .012 with remington or winchester brass. One reason is that the chamber on a breakaction rifle is slightly larger to allow for the cartridge to slip completly inside the chamber to lock up and be fired. A bolt gun can have a tighter tolerance in the chamber. So the end result is less stretching. Check some of your brass before resizing if you are getting hard to resize brass the case may of expanded slightly to fill chamber area. This will make the brass harder to resize and stretching will be more promenate. If this is the case you will get a couple less loads out of your brass. Closer attention should be paid to check for signs of fatige. Hope it helps

 

[243winxb]

Neck Diameter of a Loaded Round

The neck diameter of a loaded round should never be larger than SAAMI specifications. You can find drawings here. http://www.stevespages.com/page8d.htm As you can see the 22-250 is around .254" but has a taper to a thickness of .256" near the shoulder. If your loaded rounds measure .254" or smaller, i would not worry about reaming or turning brass necks. If the Diameter becomes to large, the bullet will be trapped/crimped into the neck, causing high pressures. This trapping/crimping also happens if brass gets to long, over its Maximum trim length.

 

[jbkebert]

I would recommend a book called the ABC's of reloading. I have not been reloading for all the long a year or so. I have reloaded shot shells for 10 years but am fairly new to rifle. I read this book 3 or 4 times before I loaded my first shell. I also find myself refering back to it often to answer questions that more I get into the hobby. The THR has been a great help and recommend you get all the info you can. ( I know I do). The book I have found to be a great refrence and worth the $20

 

[fguffey]

We assume brass stretches and flows, if brass flowed forward when fired, where are the skid marks? If the brass was not measured before firing, and (or), if head space is not known before sizing, measuring the case length before and after sizing has no value, the .010 would be equivalent to 'working the brass'. When fired the full length size case expands and conforms to the shape of the chamber, I have formed wildcats (30 Gibbs) that were shorter after fire forming. The full length size case is smaller in dimensions than the chamber, when fired the case expands to the chamber dimensions, this can shorten the case, sizing after firing can reduce the dimensions of the fired case, the brass must compress or flow, sometimes a little of both.

As the body of the case starts to be sized, the diameter of the body of the case is reduced in diameter, the shoulder moves out (up) and as a results the neck is pushed out (up), after sizing, the case is longer, I can not say the case stretched.

Case stretch, if the case stretches it stretches between the case body and web if the case body locks onto the chamber and the case head moves back against the bolt face when fired, when sizing I determine head space first, adjust the die to the shell holder to cut down on all that traveling=stretch.

Then there is flow and why there are no skid marks, or does the chamber and sizer die work like a one way clutch?

F. Guffey

 

[ole farmerbuck]

As the body of the case starts to be sized, the diameter of the body of the case is reduced in diameter, the shoulder moves out (up) and as a results the neck is pushed out (up), after sizing, the case is longer, I can not say the case stretched

Hmm I was thinking the case was getting longer when pulling the expander out. I'll resize one tomorow without the expander and see.

 

[243winxb]

this would be stretching http://www.thehighroad.us/showthread.php?p=5131161#post5131161

 

[fguffey]

IN the perfect world of sizing there are new unfired cases, then there is annealing, in the absence of new cases and annealing there is guessing. I would suggest measuring the case before sizing, fire and measure again then size and measure again, I have FL sized cases, , dropped the sizer assembly into the case, lowered the ram to remove the case from the die, removed the case from the shell holder and measured the case before the sizer ball was pulled through the neck, the case length was longer after sizing than before sizing. After installing the case and assembly in the press and lowering the ram to pull the sizer ball back through the neck I found the cases that needed annealing more difficult to expand. Stretch at the beginning of this thread had to do with pulling the sizer ball back through the neck after FL sizing with a .010 increase in length.

I have formed 35 Whelen, 30 Gibbs, 338/280 etc., I have 308 Winchester, 257 Roberts, 8X57, 7X57, 7.65X53 etc. all with 30/06 case head stamps, in all the above stretch does not cover it, stretch, compresses and squat does not always mean the case gets longer, upon completion of the 30 Gibbs process, the cases shorten, compresses or squats .040 thousands, the term 'blow out' does not mean forward, when the case expands and fills the chamber the neck is pulled back to allow the case to expand, or, the case expansion pulls the neck back, after all that work on the Gibbs cases I did not not like the ideal the chamber length was longer than the case by .050 thousands, the Gibbs neck length is .217 (+ or -), that is not much bullet hold (tention), I made some changes and came up with a case neck of .257, this moved the case mouth closer to the throat and the longer neck covered more of the chamber.

F. Guffey

 

[ole farmerbuck]

Ok, i measured one before sizing. It was 1.908. Resized without expander was 1.918. Then with expander it was 1.916. The expander must have made the shoulder give a little going in? So much for what i thought was making the case longer! I sure can learn a lot here by asking. Thanks guys.

 

[ole farmerbuck]

By the way, my neighbor said he has been trimming his cases before he resizes. He might change!

 

[fguffey]

Ol Farmerbuck, I waited, no one had anything to add, I trim first if trimming requires grinding the pilot meaning I will not get into a tug of war with the pilot when it is difficult to install or remove. I have a Gracie case trimmer, it sets up on the shoulder of the case, the length of the case from the head of the case to the shoulder is not a consideration when trimming. More times than not I use a trim/forming die with a file then size, when forming with the trim/forming die the case must be sized afterwards. so it is trim first then size.

My opinion, trimming first then sizing works unless the case is trimmed to maximum length, trimming to maximum length should work with chambers with head space issues, head space can be added to the length of the case between the head of the case and shoulder, back to Gracie, it sets up on the shoulder, the case from the shoulder back to the head of the case is just something to hold on to, and I measure after firing, after trimming after sizing.

Then there is the length of the chamber which is not difficult to determine.

F. Guffey

 

[243winxb]

Check the brass length after FLRS or Neck Sizing. Trim if needed before loading.

 

[AntonyDaGrate]

Just a thought from someone new to reloading but if i was having that problem i think i would mic the ball sizer and see if it has buildup on it.
I have read that some people use a jewlers past and buff the sizer to keep buildup from happening also a nylon brush with a good bore cleaner is not a bad idea. the fluoride rinse probably isn't necessary
but if it makes the decap pin last longer what the hec

 

[Doug b]

Nope bore cleaner or bore solvent is not good for a casing if that is what you are referring to.

 

[AntonyDaGrate]

Sorry should have been clearer. I was referring to the die itself.

 

[Doug b]

Yep I wasn't sure Tony.Welcome to the THR.

 

[moosehunt]

Obviously, we're talking to a relatively new reloader here (farmerbuck), so let's get back to basics, so that he can learn. A case does not stretch during resizing. When a cartridge is fired, it expands to fit the chamber. If there wasn't room for it to expand in the chamber, then you wouldn't be able to get it in the chamber. In otherwords, the case must be smaller than the chamber in order for this whole shooting thing to take place. Generally, SAAMI specifications for chamber size are significantly larger than SAAMI specifications for case size. After firing, the case reduces in size to again be smaller than the chamber (otherwise, you couldn't get it out of the chamber). But, in virtually every situation, the resultant fired case is larger in diameter after firing than it was before firing, being on the upper end of SAAMI specifications for case size (assuming that your chamber falls somewhere in the specification of SAAMI, which in fact are quite loose). So now we go to the step of full length sizing, which is going to reduce the diameter back to something on the low side of SAAMI diameter specifications, i.e. case specifications, in order to assure that it will fit in any SAAMI chamber. We can't be "hoping" that the intended chamber is large enough and the case small enough; we must be certain). When that case is squeezed down in diameter, the material comprising the case (brass) must go somewhere. In the confines of the die, it can only go one place, and that is up towards the opening, i.e. the neck. There is no place else it can go! The obvious result is that the case is now longer. Basic when you think about it. The reason (at least a major reason) that some folks don't full length size, only neck size, is to eliminate this squeezing back down in size (diameter) and the resultant "growth" in length. Neck sizing works because you are putting the reloaded shell back in the same chamber (KEY--neck sizing is ONLY used when the same shooter is being employed) that it came out of, hence it fits. Even then, after about 4-6 reloads, the expand/shrink of shooting becomes reduced enough that a dose of the full length die is needed in order to get the case into the chamber. So, the reloader guy needs to realize that every time he full length sizes a case, it IS going to get longer. Depending on your individual chamber size and die size, this degree of lengthening may require trimming every reloading cycle, or maybeso only every 2nd or 3rd. If one chooses to neck size, trimming is generally reduced to that one in 5 or 6 reloadings that reqires full length sizing, because you are not squeezing that case down each time. Generally, it is quite advantagous to anneal at this point, also.

Basic point to all this yack is that yes, your case will increase in length significantly every time you full length size it (but you aren't "stretching" it), so what you are seeing is normal. If you full length size (forget the caliber/cartridge), you will have to trim on a regular basis, i.e. every or every second reloading.