sizing questions?

A

axis223

New member
I'm only loading for 223 rem varmint and target rounds and currently FL size because the brass is from different bolt guns.

Im totally new to this and was wondering about neck sizing only. I know that FL sizing takes a toll on the brass so trying to make my millage last a bit longer.

I also see a lot of stuff about don't bump the shoulder back too much,etc and have no clue what they are talking about.

for a new guy should I worry about this or just do what I have been doing?
 
If you're loading for just bolt-guns, it's not likely that you're getting too much case stretch from firing, which is what full-length resizing is meant to correct. I'd suggest that you try neck-sizing only on a few rounds and see if they still chamber freely in your guns. If so, you should be fine with neck-sizing only. I've neck-sized only in my M1's forever to save wear and tear on the cases; something that's normally not suggested on semi-auto's. I've had no problems.

I've never understood how, if your dies are made correctly, it's possible to "bump-back" the shoulders on bottleneck cartridges, unless of course they've been stretched beyond standard dimensions by firing in guns with weak lock-up or excessive headspace. In those cases, bumping back is just resizing back to what should be normal dimensions.
 
now when I use a neck size only die I can only shoot those rounds in the gun they came out of correct?
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Generally, but not always true. It depends upon which gun has the larger chamber. If you shot the rounds in the gun with the slightly smaller chamber, the neck-sized loaded rounds would fit into gun with the larger chamber. However, If you shot the rounds in the gun with the larger chamber, and then neck sized, they may not freely chamber into the gun with the smaller chamber.
 
If the cases came out of another rifle, full size the round. If fire formed in your rifle, you can neck size only. Not only follow instructions that come with the dye, but read up on neck sizing BEFORE you purchase. You may decide you want bushing style neck sizing dies or non bushing type.

Please ask here for help. I am incapable of giving definitive answers but others here will be able to do so.
 
No not necessarily in response to post #3. Consider the slight variations that can occur in chamber dimensions as well as sizing die dimensions and if several dimensions were favorable, one particular sizing adjustment could chamber in different rifles. I am not familiar with using a neck sizing die only as opposed to getting by with partially neck sizing with a full length die but that could make a difference. But certainly not all neck sizing operations will chamber in rifles of course. A good forum discussion could be exactly what constitutes full length sizing or neck sizing when using a full length die. For example, if you are not setting the shoulder back, is this considered by most to be partial neck sizing only. A number of variations could enter the equation. Is the classic definition of full length sizing when the shoulder is set back and the round returned to original dimensions? Probably everyone has their own definitions and there may not be complete agreement. Sometimes I consider that I neck size only with a full length die while at other times bump the shoulder back, whatever is needed for proper chambering. Are you only neck sizing by not setting the shoulder back but still maintaining full length dimension to your chamber.
 
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Resizing..bumping. Sort of the same thing. Think of your FL sizing dies as a means to return your brass to an industry standard size. But, you may not have a rifle chamber that is that same industry standard size. Let's say, for the sake of this discussion, that your rifle chamber has dimensions slightly larger than standard. You fire the round and your brass becomes fire formed to your chamber size. From here, you can FL size or neck size. If you neck size, then your brass only gets worked at the neck, and the rest of the case remains sized to your chamber. Note that neck sizing is better done for bolt action rifles than for a semi-auto like an AR. If you FL size to the max amount that your die will allow, you will have resized it to the industry standard, but may have sized it more, and smaller than your rifle chamber needs. You will have 'worked' the brass more than necessary. Instead of FL sizing to the max, you can set the die to resize to a desired lesser amount, which will move back or reset the case shoulder (bump it) to your desired degree.

The 'bump' approach will give you the benefit of brass that is all sized to the same degree (consistency) and will 'work' it to the minimum amount, for longer brass life. And you won't have lost the benefit of having fire formed the brass.

Obviously, this is best done for brass that is for the rifle in which the brass was fireformed.

And...i've just outlined the very basics. Others will likely want to add their views and suggestions.
 
Condor and Country haven given you much more complete explanations on resizing. I just want to confirm that when I suggested neck-sizing only to you earlier, I actually meant that you should use your existing full-length dies, but to screw them out a turn or two, to only partially resize the case. Because of the taper of the case body, doing so will reduce the working of the case body by a great margin and still resize enough of the neck portion to hold your bullet in place.
 
I also see a lot of stuff about don't bump the shoulder back too much, etc and have no clue what they are talking about.
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Same here, I have bump presses and I have presses that do not bump and bump sounds to much like something that happens during an accident. And then there is the illusion; reloders believe the shoulder moves when they size the case and they believe the shoulder moves when the case is fired. I fire cases and the shoulder does not move, I form cases and the shoulder does not move and then there is sizing; same thing; the shoulder does not move. In my opinion the shoulder moving is a bad thing when firing and sizing. Again I have bump presses; I have instructions from RCBS that covers bump, cam over and non cam over. My cam over presses are bump presses.

Condor and Country haven given you much more complete explanations on resizing. I just want to confirm that when I suggested neck-sizing only to you earlier, I actually meant that you should use your existing full-length dies, but to screw them out a turn or two, to only partially resize the case. Because of the taper of the case body, doing so will reduce the working of the case body by a great margin and still resize enough of the neck portion to hold your bullet in place.
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“A turn or two” that has a good sound to it; a turn or two could be .071+ or it could be 143+, I have neck sizing dies, I do not use them but I have them just in case. When sizing a case the neck is the first part of the case that makes contact with the die, and then the case body of the case contacts the case body of the die. When the case body contacts the die the shoulder and neck of the case is pushed up. Many years ago Lyman claimed the shoulder took on a slight radius before the shoulder contacted the shoulder of the die. I do not have a problem with any of that except when sizing a case to fit a chamber I avoid returning the case to minimum length/full length sizing. The difference between the length of the case when sizing to fit and returning a case to minimum length can be .005” when sizing a case for a good chamber.

F. Guffey
 
I reload for my Rem 700 308 cal. Benchrest shooting only, tried neck sizing, Redding S type bushing dies, wnt back to the standard RCBS F/L die. Average runout .001 & better. I measure my fired case with the RCBS Precision Mic. Set my F/L die with the lowest shell height from the Redding competition shell holder set. Keeps my headspace to .001 sizes the neck & works the brass to the minimum.
 
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Just a couple thoughts; .223 and 5.56 brass is plentiful so I would suggest you concentrate on other aspects of your reloading and get good shootable ammo now and worry about case life later.

I only reload for "accuracy" in 2 guns; a .223 which I "neck" size only, and a bolt gun in 308 that I have a collet die for neck sizing. My other rifles get full length sizing (a Garand and a couple mil surplus). I neck size by marking a.223/5.56 case with magic marker and back off the F/L sizing die until there is just a few thousandths of the neck not being sized. May not be "proper" but it works for me...
 
mikld does have a good point. You could just FL resize and shoot. I'll take a guess and say that's what most folks actually do. And what springer99 said about using the FL die for Partial Resizing is very close to doing exactly what we talk about when 'Bumping' the shoulder. I partial resized for many years. Worked great, but works best for cases that have significant body taper, like my 270 and my 220 Swift. I have found that on cases that have little body taper, I ran into what Mr Guffey was talking about. The shoulder moved forward if I didn't go far enough with the die to bump the case shoulder back to where I wanted it. And that term "bump", to me is just a word somebody put to use to say that they just pushed the shoulder back a little bit. They just bumped it back, but didn't move it ALL the way back.

If the OP is shooting an AR, just FL size and be done with it. If he's moving to a bolt gun, now's the time to fiddle around with degrees of sizing. It's just part of the addiction that we have to get more and more down to the teeny details. Mr Guffey is the guy with the serious details, but I think we have to be to some degree an experienced reloader to understand and appreciate all of what he has to say.

If the OP had been around this forum for a while, he'd know that FL sizing, NK sizing, Partial Resizing, Bumping the shoulder, Collet Dies, and Bushing Dies have all been discussed to the infinite degree, though I wouldn't say that everyone agrees on everything now that it has been discussed. Heck, just the varied terminology that is used can be confusing. Different ways of saying about the same thing.

And that thing that Mr Guffey just mentioned about using the die to size the case to FIT rather than sizing it to the minimum possible with the FL die is probably the best way I've heard anybody make that point.
 
As you continue to load and size for more and more rifles and rifle calibers, it becomes obvious that different sizing requirements are called for. There is no one sizing that fits all. Adjust the sizing to the rifle for proper chambering without over working the brass which could mean setting the shoulder back excessively with the possibility of case separations to follow. My preference is when the sized case chambers with just a slight resistance, which doesn't happen that often, suggesting that the round is more properly centered. However some have taken exception to that which is of course OK and understandable. Tilting in the chamber could also be due to the way the cartridge is being held by the extractor and other factors.
 
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Are you shooting a bolt gun? If not, continue full-length sizing.
If you are using a bolt gun, then, after firing in your gun, you can neck size (but, for the small gain, it really isn't worth that much and .223 cases aren't that expensive.
 
for a new guy should I worry about this or just do what I have been doing?
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Yes and maybe yes .

Lets start with bumping the shoulder back . First you need to understand why if at all you need that . When you fire a bottle neck case it expands to fill the chamber . Brass has elasticity so after fully expanding to your chamber it will spring back just a tad and that allows you to extract the case . It is that spring back that allows you to only neck size because that case will still fit in your chamber .

Now after neck sizing a few times in a row the case will have expanded/stretched to a point that extraction is harder do to it sticking in the chamber . This is because they no longer spring back as much and stay pressed against the shoulder & bolt face as well as the chamber walls . Those same cases will be hard to re-chamber as well if you only neck size again .

At that point you will need to FL size the cases in order to get them to freely chamber in the rifle again . FL sizing reduces the diameter of the case body as well as "bumps" the shoulder back all in one process .

OK now to the interesting part . The term FL sizing , Some say a case is only FL sized if it is returned to SAAMI minimum . The thing is most of us don't need that in order to get those expanded cases to chamber freely again . In fact you often just need the shoulders to be "bumped"/ pushed back .002 or so to get that to work . While a true FL sizing will likely push your shoulder back .006 to .010 which will result in excessive head clearance in the chamber .

So how do you know what .002 bump is you ask ?? Well you need a comparator of some type . This is a device that allows you to measure your fire formed cases . The measurement you want is from the head to the datum point on the shoulder . The datum point "is" a specific point on the shoulder of most bottle neck cases , It's usually somewhere in the center of the shoulder .

I use the Hornady head space comparator http://www.midwayusa.com/product/47...-headspace-gage-5-bushing-set-with-comparator

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You can make home made ones using spent cases like 40cal for 308 or 3/8" bushings/spacers that will preform the same function .

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That function is NOT to measure the head to datum point but to COMPARE your fired cases to your FL sized cases . You first measure your fire formed cases . Lets say the measurement you come up with is 1.628 . Now that you have your fire formed case measurement you now know what to FL size your case to . If your fire formed case is 1.628 and you want to bump your shoulder back .002 . You will want your FL sized case to measure 1.626 using the exact same comparator you used to measure the fire formed case . Remember you are comparing one to the other . If you use two different tools , inserts , spacers , or cases you will get different measurements with each .

I hope that explains bumping the shoulder and some of FL sizing . Now to FL sizing to much meaning bumping the shoulder .006+ then is needed to get your case to chamber freely . When the firing pin hits the primer it pushes the cases fully forward until the case shoulder stops on the chamber shoulder ( non belted rimless bottle neck cartridges ). If your cases is sized from datum to shoulder really short . When the case is pushed forward it will leave a gap between the head and the bolt face of that same distance-ish resulting in excessive head clearance . Now when the case expands it will stick to the chambers wall leaving that space between the head and bolt face . The resulting pressure in the case will force the head of the case back up against the bolt face . But wait how can this be if the case body it firmly stuck to the chamber walls ? Well it forces the case to actually stretch rather the slide back . This stretching happens at the web of the cases where the case wall start to become thinner then they are closer to the head .

If you continue to size your cases smaller then needed . They well continue to stretch in that area resulting in the wall getting thinner and thinner after each firing . This thinning is what you can feel when sliding a sharp pick inside the cases . This thinning of the case wall will result in case head separation .

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I hope that helps explain a few things you were not to clear about . I've now wrote so much and it's taken so long that I'm not remembering what all I've said and there has likely been 5 other members posts since I started writing . So I'll stop here and answer any questions to what I posted if need be
 
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Good explanation MG, you've covered those bases very well. Too often I guess we assume that everyone intuitively knows what we are talking about and don't go into enough detail. But my excuse is partly that I'm doing this thing on a small tablet that is difficult to type and manipulate and I tend to cut explanations to a minimum. The OP no doubt appreciates your detail. But I've never had those degrees of separations that you show in the photos; only once with a .45-70 round. However to give you the benefit of the doubt, those have to be range cases and not your own ;).
 
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My simple reply would be to put a feeler gauge of about .003 between die and shell holder, leaving the die just short of touching shell holder. If that works, you can increase that a bit. Your shoulder should from that time on remain stretched to fit between breach face and chamber shoulder, an your brass will no longer have to stretch to fit he case on firing. This works well on a bolt. If closing the bolt becomes difficult, bring the die back down until you gut good feeding.

Neck sizing is not usually recommended for looser action types, or ones that don't easily slide completely into battery.

All of my bolts function well with that procedure. You may be able to interchange with other otger guns but it is not guAranteed, If you find problems, I would segregate brasses. I bought hornady brass to use only for my 30-06 semi auto. Keeps them separate.

All of the detailed info he r e is good. This is the simple thing that you will pick up in a basic manual.
 
However to give you the benefit of the doubt, those have to be range cases and not your own
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Sadly those were in fact my cases that I fired and reloaded 3 times . That was a result of me following the die instructions . I screwed the die down until it touched the standard shell holder then gave it a 1/4 to 1/2 turn more . That resulted in my cases being sized .009 shorter from head to datum then needed . That ended up giving me excessive head clearance resulting in the stretching I explained above . In my defense those were my first reloads and I was loading strictly per instructions and manuals . I saved a few of those cases to remind me what not to do and to share with others as I'm doing now .

Here are those cases next to other cases that had been sized correctly and reloaded 8 times and annealed once

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Case separations with straight walled cases like the .45-70 must have a slightly different explanation than separations with bottle necked cartridges but I'm not sure what it would be. My .45-70 separation was with a new Marlin lever action but the brass was part of some I had bought used. Examination of the remainder revealed pending separations so were discarded. Another straight walled case separation, it was something like a .44-40 or similar in something like a Contender, happened to another individual while at the range. I happened to have the handy bent paperclip tool for checking pending separations with me so I was able to clear his firearm without further ado. However it happened a few more times until he finally called it quits and back to the drawing board with his reloads. What might cause separations with straight walled or near straight walled cases? Are we still talking about headspace issues or something else?
 
Are we still talking about head space issues or something else?
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Well that's an interesting question seeing how they head space off the rim . I only load one rimmed case and that's 30-30 . The problen there is the rifle is a bolt action so although it head spaces off the rim I can head space it off the shoulder as well kinda like you can belted cases .

A quick search on 45-70 head separation came up with two recurring possibilities . Head space issue letting the case stretch in hot loads and lever guns bolts flex back because they don't use locking lugs . Running hot loads in a lever gun can cause case stretch . My VERY limited reasearch here seemed to indicate hot 45-70 loads from a lever gun may only give you 2 or 3 loads before the cases are bad .

Does any of that sound possible with what you experienced .
 
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