Confused about Resizing and Head Space
 

Hey guys,

I thought I understood what the resizing die was doing by backing off the die from the shell holder but I'm again confused.

I recently was introduced to a headspace guage. It is a tool that tells you how long the cartridge is supposed to be so that the bullet will be just .01" from the grooves etc...

So is it resizing that adjust the headspace or is it the depth of the bullet seating?

Doesthe resizing at different heights from the shell holder change the angle of the neck?

If I resize a shell way off the shell holder will it cause the shell without a bullet to no longer close in the chamber?

Thanks

Tom

RE: Confused about Resizing and Head Space
 

Ok, headspace is not the same as distance from rifling. Headspace is for the shoulders only. Thoat gauge or mic or stoney point OAL gauge can measure distance to rifling. Adjusting your sizer up and down off the shell holder, adjusts the shoulders to fit your chamber.

I highly recommend you just cam over or FL size just starting out. In fact, most of my cartridges, I just cam over, in other words, screw in the shell holder until contact, and then another 1/4 turn.The ones I don't, I use a lee collet die.I used to go to great pains to do the "partial Full length" sizing you do, but found I can get more consistent ammo/shoulders, even with slightly more wiggle room, by just FL sizing. If I have a gun and die combo that gives me more than .003"extra headspace, I will find out if the gun is the culprit or die. And usually its the die, and I have my gunsmith cut just a little off bottom of my die, just a few thousands, to get the combo right. It doesn't take much. That way you dno't have to fool with the stoney gauge or candles to see where the brass is.

RE: Confused about Resizing and Head Space
 

Ok so now I got it that the sizing is for the neck only.

Does the screwing it down an extra 1/4 turn apply to belted magnums? Will the belt go into the die?

Also please answer this question directly. If I pull the sizer die way up off the shell holder and resize a case will the action on the rifle close? What I'm interested in knowing is whether or not you an size a case to the point where it will not allow the action to close.

One last one, are you sure I should go a 1/4 turn closer to the shell holder, because the book says to back off 1/4 turn?

Thanks

Tom

RE: Confused about Resizing and Head Space
 

In answer to your latest question, Yes the belt will go into the die but if the die is cut properly and you adjust the die as Bigcountry said you will have no problems. As for closing the bolt, if the cartridge was originally fired in that rifle you should have no problems closing the bolt, UNLESS the case neck is too long. You should always trim your cases after sizing to the 'trim to length' specified in the reloading manual. Even if the cutter just touches the case mouth. Trimming squares up the case mouth to the bore which attributes to better accuracy.
Also, if you try to chamber partially sized cases into another rifle of the same chambering you may end up going to the local gunsmith to have it removed because chambers in different rifles can vary.
IMHO, I suggest FL sizing.

RE: Confused about Resizing and Head Space
 

Tom, you are right that with your press, I don't think they want you to cam over like with mine they do. Also, you want to back out with carbide dies also.

To answer your question on pulling the sizer way up, the answer is not direct. I am sorry, just the way it is. If the brass was fired in your rifle, then yes, and that depends on if your dies pulled the neck or not on its way out. If youlube the neck good it shouldn't much. Bad part about pulling the sizer way up is, you didn't size the neck possibley all the way, and now it doesn't hold your bullet well. Thats the reason the stoney point head gauge is invaluable to me. You can take a fired piece of brass from "your" rifle, and say it measures 3" from the neck to the rim. You can turn in sizer until you see start measureing 2.998". That way you know you just bumped your neck but sized your neck all the way.

If you get new brass or brass from a range fired in alot of rifles, then you have to FL size. At least the first time.

Hope it helps.

RE: Confused about Resizing and Head Space
 

Ok so let me see if I can sumerize this,

New Brass should be full Length resized.

Once I fire a piece of brass in my rifle the brass has expanded to fit the chamber so I only need to resize enough of the case so that it only effects the shoulder and neck portion of the case. But your telling me that I should just full length size it anyway. Correct?

How much would just sizing the neck area of the case (partial)on already fired brass add to its life?

In general if I'm not going to full lenght size a shell after its first firing what is the maximum distance the die should be from the shell holder or is the 1/2 turn suggested by the book about it?

Last question,If I don't F/L resize the cases before each loading will I have to test my groups first with the unfired F/L resized brass and then with brass that has been fired and partially sized?

I'm heading out of town tomorrow but I'll be back on Sunday.

I look forward to seeing the answers.

I appreaciate everyone's patience with the noobie questions.

Tom

RE: Confused about Resizing and Head Space
 

Actually I just put 2 and 2 together with what another poster said about burning the shoulder of the cases to see when the die just hits them. I understand this part of the partial resizing issue. Wow. That felt good.

If you guys could get to the other questions I added that would be great.

Tom

RE: Confused about Resizing and Head Space
 

I sometimes do resize when buying a new bag, or just go and fireform it if its not too bad shape. But these days brass comes so banged up, with dented mouths and dented shoulders I go ahead and FS and then trim.

Starting out, FL may be easier and what I suggest for everyone. It confuses Newbies alot.A personjust starting can't make match ammo right off the bat. Need to learn the basics. And maybe your chamber matches your die pretty good anyway, I just am in a cycle of my relaoding where I like to simplify my life. FL sized brass extracts easily, and more what I call hunter friendly. Thats more important these days than making my groups go from 1.2MOA ot 1.0MOA. I have found that if your dies matches your chamber decently, the extra work Paritial FL sizing just ain't worth it.

Depends how much headspace you had in your rifle. If you rifle is really stretching out your cases,life is extended a whole lot, but other than that, it just works your case body and necks less. Usually yoru necks split or primers fall out before anything else and therefore kills the life of your case well before case body or rim rips off.

Depends on yoru gun chamber. Depends how much your pushing the shoulder back. If you have to go too much off the shell holder, then either die is out of spec or your chamber is out of spec with excessive headspace. See what the stony point or candle soot method tells you first. I know I was helping Mossyoak33 one day and he had to turn his die almost a whole turn if I remember to keep from bumping his shoulders back.

Very possible but depends on what level of accuracy your after. For hunting, it may open your groups up .5" or just the occasional flyer. Big deal. For serious target work, you don't want that.

thats the reason I went to either lee collet or FL sizing. I can count on my cases being repeatable and same dimentions every time. I may lost some accuracy but sure not enough to keep me up at night.

RE: Confused about Resizing and Head Space
 

Looks like bigcountry answered your questions pretty well. but to extend the answer on case life: It can vary by manufacturer and even by lot for a given manufacturer. Your powder charge can also affect case life. Every time you fire a round, the brass 'flows' toward the case mouth - hence the need for trimming.
The area most affected by this flowing of the brass is the area around the web. Besides neck splits and loose primer pockets you will need to examine this area and watch for a bright ring around the case. If the brass gets too thin here, your case will rupture or even completely come apart.
Also, understanding how a FL die works, if you back the die out of the press (not adjusted to the manf. instructions) it will only size a portion of the body and neck and will not touch the shoulder. The amount of sizing of these areas depends on how far you back it out.

RE: Confused about Resizing and Head Space
 

Thanks for all the info guys. I'm going to making my first set of ammo this week and will fire it off on Saturday. I'll report back.

Thanks again.

Tom