Tired or FL resizing 308, how do I bump shoulder?

callen3615

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Hi, I have been full length resizing for my 700 for about a year now. Im really getting tired or lubing cases and trimming off excessive length. I have read about setting up a FL die to just bump the shoulder back. I have read about how some people just neck size a number of times and the bump the shoulder back.

I would like to start doing this, can my FL RCBS die be used as a bump die? What is the old school method used to setup a FL die for shoulder bump without a head-space gauge?

Thanks
 

shoot4fun

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    Re: TIred or FL resizing 308, how do I bump shoulder?

    I use a Forster bump die with bushing for my 308 sizing. I am having to FL size about every third or fourth firing.
    You can find them at Sinclair and Graf's.
    If I understand what you're asking, I don't think you can shoulder bump with a FL die without FL sizing the case. If I am wrong, I will surely be corrected quickly.
     

    Gascan775

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    If the cases were fired from one gun and your going to re-fire them in the same one then I think you can get away with doing just neck sizing. The brass is fire formed each time you fire so the cases should be ready to go aside from the neck. Unless your having a hard time closing the bolt, you shouldn't need to even bump the shoulder back.

    Get a neck only die (I use Redding neck sizing die)
    Remove the expander ball (Some may disagree with this but it works and you can see and measure the difference)

    Now, just size em, which only squeezes the neck.
    I get better consistency (neck tension) which gives me better groups.
    Again, unless your running this ammo in other rifles or having issues closing the bolt this will keep you from impacting the case length and having the mess with the case growth. It works for me...

    ** If your running the cases in multiple rifles you really need to FL size the brass to be sure that it will feed in all of them.

    As someone said - If you want to bump "just" the shoulder you will need a die specifically for that a FL won't do it without hitting the whole thing (ie: start trimming).
     

    targaflorio

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    You need to measure the headspace. Comparator, bump gauge and caliper, other headspace gauge (e.g., Dillon), or my preferred method,rcbs precision mic.
     

    callen3615

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    Ok thanks. I have a neck sizing die but i was under the impression that the shoulder would grow as I shot the brass. And yes these are all going back into the same rifle.

    Thanks
     

    shoot4fun

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cpt. obvious</div><div class="ubbcode-body">Ok thanks. I have a neck sizing die but i was under the impression that the shoulder would grow as I shot the brass. And yes these are all going back into the same rifle.

    Thanks </div></div>

    The shoulder does move forward. BR shooters have found that using a die that bumps the shoulder back just slightly, maybe .001 to .002, while resizing the neck (and not all the way to the juncture of neck and shoulder) gives better accuracy than neck sizing alone. Plus, this method allows you to control headspace.
     

    azimutha

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    WIshortmag makes a good point about this applying just to one rifle. I would agree with shoot4fun, however. Details on that: I use a FL die to do a partial-FL resize. You set up the die for normal FL resizing, then back it off until you're only bumping the neck and shoulder back .001-.002. I've had good luck with the Redding S die and a titanium bushing. But I otherwise would have considered using the Lee collet die.
     

    armorpl8chikn

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    Here:

    Bullet seating depth:
    You can make up dummy rounds. Take a fired round and resize the neck 3/4 way down with a FL sizing die. *Yes you can use a FL die in this manner.* Greg L has mentioned it a time or two in these pages. Seat a bullet a bit long in the case and smoke the bullet with a candle. Now slide the cartridge in the action and try to close the bolt, won't close so extract and notice the lovely rifle land marks in the smoke. Wipe the smoke off and seat a bit deeper. Smoke the bullet again and rinse and repeat until the bullet shows no rifling marks, you are now pretty close to jam length of THAT particular bullet if you switch bullets I would reccomend new dummy rounds and repeat this process. With a dummy round like this you can use it to set up your seating die.
    Better: Take a dremel tool or small hacksaw and split a case new is ok but a fired case that has been neck sized almost fully to the shoulder will be better. Split to just past the neck shoulder junction. Insert bullet and insert round into chamber, close bolt and extract round carefully. Now measure length to lands with bullet comparator and calipers. You may need to use small vice grips (needle nose is good for stuff like 223) and lock on neck to hold bullet tight in case, then measure with comparator. You may need to do this a couple times to make sure the bullet isn't sticking in the lands and pulling out a bit as you extract. If you stick the bullet just knock it out carefully with a coated cleaning rod, I usually drop an 80gr 224 down the muzzle and it knocks a larger bullet right out. If you stick an 80gr 223 in the lands of course you will have to use the cleaning rod.
    <span style="color: #CC0000">FL die setup using smoke:</span>Smoke the neck of the lubed case lightly on one side. Put your sizing die into the press and screw down to shellholder and back out a full turn. Now take the smoked LUBED (never forget the lube)case and run full into the die and back out. What do you see? How close are you to the shoulder? Using this method you can set up to lightly bump the shoulder or almost bump the shoulder and all points in between. There is nothing you can't do to a case with a FL die. If you set one up correctly it is all the resizing die you need to make brass last just as long as the primer pocket will hold a primer.

    These are the old school methods that I have used for years and my brass lasts as long as anyone using a neck die. I trim very seldom. This is the third time I have posted this info. Set up a FL die in this manner and you don't need a neck die.

    Use a candle for smoke.
     

    PeterN

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    Don't try to Partial resize with a full length die. It's best to neck size til they get tight and then bump the shoulders back .002 or so. You will not escape trimming but it will not be as often
     

    Bayou

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    I bump the shoulder in 308 with a Redding body die and neck size with a type S bushing die. I measure head space on every case I reload. My head space target value is what I get on once fired new brass. When the head space measures more than that I bump. I also use a Sinclair chamber gauge to show what max case length the rifle can accommodate. I subtract .010" from that max length and trim anytime the case exceeds that. This lets you trim a lot less than if you use SAAMI specs.
     

    Tripwire

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    If you understand how a FL die works, and what happens to the brass as it's being pressed into the die, then you will answer a lot of questions for yourself.

    The stigma attached to "parial resizing" with a FL die is soley the fault of people simply not setting up the die correctly to begin with, beit on purpose, or by ignorance.

    As the brass is being pressed into the FL die the first thing to contact the interior of the die is the case body itself. This portion of the case is squeezed down in circumferential size progressively over it's length. The further into the die, the more the case body diameter is reduced. This causes the shoulder to move forward because the brass has to go somewhere, which increases the headspace length.

    At some point in this process the case neck enters the neck area of the die and is also reduced in circumferential size, diameter.

    Further into the die the shoulder of the case approaches and is supposed to make contact with the shoulder part of the die. When it does, pending how the die is set up, the shoulder part of the die will "push back" the shoulder of the case to whatever amount the die is set up to move it. This is entirely why it's possible to over size a case and create headspace issues.


    IMHE, the proper way to set up a FL die, using annealed brass, is to just bump the shoulder .001". This produces the minimum amount of FL sizing and still bumps the shoulder back where chambering is easy. Note the key words "annealed brass". Measuring the amount of shoulder set back is easily done with comparator gauges I made on a lathe. I actually measure the headspace on each piece of brass as it comes off the die, making sure I'm maintaining the .001" bump.

    If lubing and sizing rifle brass is too hard, or just too time consuming for you, then maybe you would be better suited with factory ammo. Shortcuts in the reloading world usually do not bode well.
     

    Blackbrush

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    Tripwire is on the money.

    I use Stoney Point (Hornady now?) tools to measure this and oal at ogive.
     

    Graham

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cpt. obvious</div><div class="ubbcode-body">I would like to start doing this, can my FL RCBS die be used as a bump die? What is the old school method used to setup a FL die for shoulder bump without a head-space gauge?</div></div>Yes, you can use a FL die as a shoulder bump die, but you may not be able to bypass sizing the outside of the neck.

    There's nothing wrong, meaning nothing inherently unsafe, with giving the case a large (unmeasured) amount of setback and using the rifle chamber as a guage for ease of chambering. The only problem is that doing that will work the brass more. If you want to bump the shoulder only a small amount you will need a caliper and a device that measures the case length at the datum line. [ http://www.sinclairintl.com/.aspx/pid=35265/Product/Sinclair-Bump-Gage-Insert ] .

    The type of brass used makes no difference in how you set up a FL sizing die.
     

    targaflorio

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    I suggest that you <span style="text-decoration: underline">can</span> physically set the shoulder back too far and thus <span style="text-decoration: underline">create an unsafe condition</span>. Think about what happens when the gun goes off. If you follow the FL sizer die manufacturer's instructions, you will prob be ok, but a headspace gauge is an important component of loading safe ammo.
     

    armorpl8chikn

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> There's nothing wrong, meaning nothing inherently unsafe, with giving the case a large (unmeasured) amount of setback and using the rifle chamber as a guage for ease of chambering. </div></div>

    BULLSHIT!
    Set that shoulder back .003 or .004 a couple times after a full house max load and see what happens. I can't believe I just read this in this forum.......wait a minute...yeah, yeah I do believe it, bad advice is fairly common around here.
     

    targaflorio

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    My normal set back for my gas gun is .003-.004" off the fired brass size. John Feamster says he sets his 7.62 shoulders back .006" from the fired dimension. Almost every piece of Federal and Black Hills factory ammo I have measured mic'd at exactly .004" below SAAMI spec.
     

    Graham

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: targaflorio</div><div class="ubbcode-body">I suggest that you <span style="text-decoration: underline">can</span> physically set the shoulder back too far and thus <span style="text-decoration: underline">create an unsafe condition</span>.</div></div>Not if you use the rifle chamber as a guage for ease of chambering.
    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body">BULLSHIT!
    Set that shoulder back .003 or .004 a couple times after a full house max load and see what happens.</div></div>I'll play: What happens?
     

    targaflorio

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    How does using the rifle chamber as a gauge prevent you from setting the shoulders back too far? You're assuming that the person would know when the bolt is closing just right (assuming we are talking about a bolt gun) and no one would screw the die in too far?
     

    Graham

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: targaflorio</div><div class="ubbcode-body">How does using the rifle chamber as a gauge prevent you from setting the shoulders back too far? You're assuming that the person would know when the bolt is closing just right (assuming we are talking about a bolt gun) and no one would screw the die in too far? </div></div>I'm not assuming anything. I'm saying that there's no way you can harm a case body by giving it the maximum amount of setback that the die has.
     

    armorpl8chikn

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Graham</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: targaflorio</div><div class="ubbcode-body">I suggest that you <span style="text-decoration: underline">can</span> physically set the shoulder back too far and thus <span style="text-decoration: underline">create an unsafe condition</span>.</div></div>Not if you use the rifle chamber as a guage for ease of chambering.
    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body">BULLSHIT!
    Set that shoulder back .003 or .004 a couple times after a full house max load and see what happens.</div></div>I'll play: What happens? </div></div>

    First off it depends on the die, your chamber and headspace. The first thing you will notice when you set back too much is excessive trimming with each firing of the reloaded cartridge. What you may not notice is what can destroy your firearm and possibly your face. It is called case head seperation and is very widely documented in every damn reloading manual in print today. There is no guarantee that your die will set back enough to be a problem, there is also no guarantee that it won't. That is dependant on several factors, again, your chamber dimensions, your die dimensions and your headspace. I have some dies that can be set to a hard camover and struggle to set back the shoulder just enough. I have other dies that will set back as much as .006 on one of my factory chambers. Your shellholder can even play a role in this. If you have a couple different manufacturers shellholder of the same size it is wise not to interchange them and use them at random as some may be thinner or thicker.
    If you set back a shoulder .006 and fire a full house load here is what happens:
    Your firing pin first drives the cartrdge forward and the shoulder contacts the shoulder of the chamber. At this point the cartridge has fired and pressure builds and the case grabs the side of the chamber, as pressure further builds the case stretches driving the head of the case against the bolt thus increasing the length of the case and causing that distinct ring just forward of the case head. This ring is your first warning. Set that cartridge shoulder back .006 a time or two more and you have a case head seperation.
    The fact that you don't know this is disturbing, and the fact you want to argue about it even more so. This information is basic reloading 101 stuff. Now tell me how wrong I am and I will let someone else barbecue you on this matter. Sure ly there are a few others here that know the basics of reloading.
     

    Graham

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body">Now tell me how wrong I am and I will let someone else barbecue you on this matter. Sure ly there are a few others here that know the basics of reloading. </div></div>Your call of 'BULLSHIT!' was more drama than it was reality. A case head separation is not going to happen by setting the shoulder back ".003 or .004 a couple times after a full house max load" unless you have a brass problem or a gun problem.

    Here's an example of someone else who posted after you did, and who sourced his information:<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: targaflorio</div><div class="ubbcode-body">My normal set back for my gas gun is .003-.004" off the fired brass size. John Feamster says he sets his 7.62 shoulders back .006" from the fired dimension. Almost every piece of Federal and Black Hills factory ammo I have measured mic'd at exactly .004" below SAAMI spec. </div></div>
    Most of the information in my above posts is available in Glen D. Zediker's book <span style="text-decoration: underline">Handloading for Competition</span> (2005 edition), pages 119 and 121. It's well written, a good read, and it covers far more than the basics of handloading.
     

    armorpl8chikn

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> I'm saying that there's no way you can harm a case body by giving it the maximum amount of setback that the die has.
    </div></div>

    Your words. Patently false words. I have seen the results of setting back a shoulder an "unknown" amount. I will concede that setting back .003" will take a bit more than 2 or 3 firings. Then again that pesky chamber issue rears its head again, how much did the case stretch the first time? I guess someone needs to tell Sierra, Lyman, Speer, Hornady and a few others that they need someone else to write their manuals.
     

    Graham

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    Re: Tired or FL resizing 308, how do I bump shoulder?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body"> <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> I'm saying that there's no way you can harm a case body by giving it the maximum amount of setback that the die has.</div></div> Your words. Patently false words. </div></div>Actually they're originally Glen Zediker's words: <span style="text-decoration: underline">Handloading for Competition</span>, page 119, first paragraph under 'Setting Up' your dies. I'll defer to Glen on this one because, as a published author, he knows much more than I do about it.

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body">Then again that pesky chamber issue rears its head again, how much did the case stretch the first time?</div></div>Chambers are not cut to a random spec.

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body">I guess someone needs to tell Sierra, Lyman, Speer, Hornady and a few others that they need someone else to write their manuals. </div></div>Somebody else already tells those companies how to write their manuals, which is part of the problem.

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body">I will concede that setting back .003" will take a bit more than 2 or 3 firings.</div></div>Oh, nevermind, I missed the part where you completely recanted what you said.
    grin.gif