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Neck sizing vs Full Length sizing?

B

BULLITT1668

Private
Minuteman
Sep 22, 2009
35
0
43
Albany, GA
#1
I always thought (from my research reading) neck sizing was needed to achieve more accurate.308 brass, but after reading "Reloading 101: Reloading basics for the new reload" (sticky on this forum) it has me all confused and restless!

I'm kinda new to reloading, I've been doing it for about 5 months now, and I've can say that I've reloaded about 400 rounds. So far, all have been only FL sized, but I've been wanting to switch to Neck sizing, but again, after reading that post. I'm not too sure what do to.

So, I go a couple of questions:

Why do "you" or do "you" not neck size?
Do you get different velocities the more you use the same brass?
How many times can you typically use the same brass before you have to FL size it again? Or, if you neck size, do you ever have to FL size your brass?

There maybe other questions out there that I'm just not thinking about right now, but I guess this will do for now.

Thanks again for all your help!

Bullitt

P.S. Here is link to post mentioned above: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=96660#Post96660.
 
#2
Re: Neck sizing vs Full Length sizing?

Different strokes for different folks. As a rule, if you have a gas gun, you better FL resize for feeding purposes. With a bolt gun, you can do neck size only, if you are lazy like me. With some custom tight chamber, you may also have to FL resize. So far, with my AIAW, I have only to neck size it and watch my case length and I am good to go. Do I see a difference in accuracy? Yes! How much? Not a whole lot more, but definitely discernable. Hope that helps.
 
#3
Re: Neck sizing vs Full Length sizing?

You need to understand the different sizing operations.
1/ neck sizing :- This is just sizing the neck of the case to hold the new bullet.
2/ Full length sizing:- This sizing both the neck and the body of the case in one pass in one die . It reduces the whole case down to a smaller size more near factory brass size.
3/ Body sizing :- This is sizing just the body of the case and not touching any part of the neck . A body die can also give a bump to the shoulder ( if you want) to reduce shoulder to base length which is headspace on a rimless round.
The use of a neck sizer and a body sizer seperates the whole sizing operation and is quite suitable for a bolt gun.
For a bolt gun once you have fireformed your brass and got a neat concentric fit you don't want to use a conventional Full Length sizing die as it will take you straight back to non fireformed brass , square 1!
If you seperate the neck sizing from the body sizing you have a situation where you can size just the body when it is necessary (maybe after a few shots it varies)to just the right ammount to fit neatly back in the chamber . This will preserve the fireformed fit. This helps to get consistant accuracy .
 
#4
Re: Neck sizing vs Full Length sizing?

Something that I like to do for allowing maximum flexibility is purchase a full length sizer die, a neck sizer die, and the bullet seater. When I need a body die only, I remove the stem from the full length sizer to turn it into a body die (make sure to remove the neck sizer bushing as well) if an when needed.

By having the full length sizer die, I can full length size and neck size in one step. This saves me the two step process of body die and neck sizer when I need to full length resize and neck size for the cost of a full length sizer die only (buy the neck sizing kit).
 
#5
Re: Neck sizing vs Full Length sizing?

I FL size all ammo for my sniper rifles. I could maybe get a little tighter groups with neck sizing. But I would also get ammo related headaches on the field. Stuck cases in the rifle, oversized brass jamming up the gun etc. I do use Redding S-type FL bushing dies with properly sized bushings so the neck will not be worked out too much.

I do use only blueprinted sniper rifles with CIP-minimum chambers and therefore the brass will not get as much worked out than in a regular "near to max specs factory rifle" chamber.

In real life all professional snipers ( I am not one of them) use duty ammo only and are "stuck" with factory made "undersized" ammo. But they hit their targets anyway. They can not fiddle around with their ammo because they have more important business to do.

I think this neck sizing business started with people having rifles with oversized and/or crooked factory chambers. Then BR people started to really shoot tiny groups. Although they hardly size their case anymore. Their rifle chambers do the sizing :)

For an all-out BR target shooting necksizing will diminish the groups but it WILL diminish also the realibility of the ammo-rifle combination to some extent. It´s a trade off.

FL sizing works for me.
 
#6
Re: Neck sizing vs Full Length sizing?

I am going to agree with DesertHK. I FL size the gas guns and Neck size the bolts. I would not say that I am lazy, but you can drive yourself crazy with stuff like this trying to account for every little detail. Necksizing does help the accuracy, not dramatic, but enough that it is worth doing. As has been noted, watch your case length. I FL size my brass when it starts getting difficult to extract.
 
#7
Re: Neck sizing vs Full Length sizing?

TA,

In my opinion, you were right about this:

"I could maybe get a little tighter groups with neck sizing."

" Then BR people started to really shoot tiny groups. Although they hardly size their case anymore. Their rifle chambers do the sizing :)"

"For an all-out BR target shooting necksizing will diminish the groups "

In my opion you may be wrong about these:

"But I would also get ammo related headaches on the field. Stuck cases in the rifle, oversized brass jamming up the gun etc. "

- Take a factory round and place it in your bolt action rifle and fire it.
- Clean the case, pocket, etc. etc.
- Neck size the case, some shoulder bump as well. Now, check that the case OAL (over-all-length) is to spec.
- Work on the bullet to lands positioning next as THAT is another accuracy key.

Now you have perfectly sized cases for that rifle. If one always neck sizes, checks OAL and inspects for cracked necks, these cases will always be more accurate than a FL case in that bolt rifle. Those "related headaches" and "stuck cases"? Are all a result of OAL problems.

"I do use only blueprinted sniper rifles with CIP-minimum chambers and therefore the brass will not get as much worked out than in a regular "near to max specs factory rifle" chamber."

It doesn't matter, Min or Max or in between. Once the case is fired, it matches your chamber perfectly. Check OAL and neck size. IF your FL sizing, you better use a min chamber as your overworking your case. Your process may save some wear and tear, but it will not be as accurate a case as a neck sized (shoulder bumped). Most BR shooters consider a full length size case load a waster of components, why? Because they are inherently not as accurate.

"I think this neck sizing business started with people having rifles with oversized and/or crooked factory chambers."

BR shooters have some of the best chambers out there. They started neck sizing because they are making the most accurate bullets that they can and they know the case is perfect.

"For an all-out BR target shooting necksizing will diminish the groups but it WILL diminish also the realibility of the ammo-rifle combination to some extent."

No reliabilty issue in the bolt rifle you made these for. OAL check.
Better ammo rifle combination with neck sizing a bolt action bullet.

And, your cases will last much much longer. Some people FL only one in five, and they know that the FL one will be less accurate. MOst of the people I know wait for that slightly stiff bolt throw before they FL and keep cheap bullets for that next FL reload.

Gas Gun? FL.

Laslty, on the topic of who is and isn't reloading vs "fiddling around." I know of no serious accuracy advocate using factory rounds when they are getting down to business.

Best, Rollin'




 
#8
Re: Neck sizing vs Full Length sizing?

Neck sizing is only if the brass is being used in THAT ONE bolt action rifle. The brass is a perfect fit for THAT ONE chamber.

If you're loading for more than one rifle, it's best to FL resize OR you have to be very careful to keep the brass separated.

The cases may or may not fit other chambers. That could result in a stuck case with the bolt locked up.
 
#10
Re: Neck sizing vs Full Length sizing?

After trying neck sizing only for a few years, I have gone back to full length sizing only on everything. If you set the die up right for that chamber you are not stretching it more than needed. And you don't have to fight with the bolt every couple of loads.
 
#11
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TA</div><div class="ubbcode-body">I FL size all ammo for my sniper rifles. I could maybe get a little tighter groups with neck sizing. But I would also get ammo related headaches on the field. Stuck cases in the rifle, oversized brass jamming up the gun etc. I do use Redding S-type FL bushing dies with properly sized bushings so the neck will not be worked out too much.

I do use only blueprinted sniper rifles with CIP-minimum chambers and therefore the brass will not get as much worked out than in a regular "near to max specs factory rifle" chamber.

In real life all professional snipers ( I am not one of them) use duty ammo only and are "stuck" with factory made "undersized" ammo. But they hit their targets anyway. They can not fiddle around with their ammo because they have more important business to do.

I think this neck sizing business started with people having rifles with oversized and/or crooked factory chambers. Then BR people started to really shoot tiny groups. Although they hardly size their case anymore. Their rifle chambers do the sizing :)

For an all-out BR target shooting necksizing will diminish the groups but it WILL diminish also the realibility of the ammo-rifle combination to some extent. It´s a trade off.

FL sizing works for me. </div></div>
A combination of Neck sizing and body sizing is all you need to load accurate sniper ammo. Hell even if a loaded round is a bit tight a body die will bring it down so it fits just sweet. Its not reccomended by the manufacturer but it works real good.
A neck size and a body size operation is still a full length size but it avoids upsetting both areas of the case at one time.
Also it avoids the stretching of the neck and shoulder outwards if you are using oldfashioned neck expander ball type dies which means you have to oversize to start with .
If you have never used a body die get one and try it I guarantee you will toss the oldfashioned FL die.
I made my first body dies 30 years ago by grinding out the necks of FL dies and chucking the decapping pin and expander ball.
That was before companies like Redding started making them. Redding made them for years on special order but never advertised them.
Only the in the know target shooters new about them.
 
#12
Re: Neck sizing vs Full Length sizing?

I have one bolt gun .308. I neck size only with a redding s type competition die set. I measured the head space on virgin brass and then headspaced it after the 1st and 2nd firing. Headspace only changed between the virgin and 1st firing. different brands of brass gave me the same headspace after firing.

I get back from the range, put the brass through the neck sizer / deprimer, then trim to 2.000 and go through the normal reload process. Haven't had to use the body sizer yet after 2 firings on the brass (winnie, lapua) that I'm using now. The way I understand it, trim to appropriate length after each firing and you'll be okay. get a hornady Headspace kit and check a couple cases after each range trip to ensure headspace.

I'm a beginner though, so I may be talking out my ass.

ETA- I also only size down 1/2 the neck so that I don't get build up at the neck/shoulder joint. I think I got that out of the redding set up instructions.
 
#13
Re: Neck sizing vs Full Length sizing?

In my AIAW.300WM I would only neck size and use a collet die to shrink the belt area about every 4-5 firings.


I recently switched the barrel out to a Bartlein done by GAP and the chamber is now such that unless I FL size I have 50% of my loads that I have to muscle to get out of the gun. I've never had one stuck, but I have to put some ass on it at times and that is something I dont want to have to do.

I agree with Victor - Set it up correct and you can getthe best of both worlds.


J~
 
#14
Re: Neck sizing vs Full Length sizing?

JFG, Sounds like you have a tighter 308 chamber in this barrel than your last. Should be a bit more accurate but at the expense of reliability.

How I wish the ultimate in accuracy was also the ultimate in reliablity. The damn opposing spectrums are always an annoyance!
wink.gif
 
#15
Re: Neck sizing vs Full Length sizing?

I've never seen a true increase in accuracy neck sizing brass. I FL it all and still shoot in the quarters or less.

FL = no worries, no hassles
 
#16
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Captain Kick-Ass</div><div class="ubbcode-body">I've never seen a true increase in accuracy neck sizing brass. I FL it all and still shoot in the quarters or less.

FL = no worries, no hassles </div></div>

Like he said, just bump the shoulder back 1 to 2 thousands and be be done with it. Just because you use a FL die doesn't mean you have to bring the brass back to min-spec. If your worried about working your brass too much have some custom dies made and you can control how much and where the sizer will set the brass back.
 
#17
Re: Neck sizing vs Full Length sizing?

I'm with CKA, Victor and C.K..

Neck sizing only will make rounds that are hard to chamber, and the issue will always present itself at a critical time when you weren't expecting it. The "hard to chamber after multiple firings neck sizing only" issue has nothing to do with OAL.

I gave up trying to shoot in the .2's and such a long while back. I prefer the OCW method of finding a sub moa load, I don't chase the lands, and I prefer no surprises on match day.

If you choose to neck size with a collet die, be sure to keep it clean and even lube the collet and its mandrel's mating surfaces. I had a Lee sart buckling shoulders on 308 when I was neck sizing, because it got dirty and dry there (another reason I gave up NS only).

If you set your FL dies to just bump the shoulder back a couple thou I actually think there's less wear on the brass than necck sizing until they need a sizing badly.
 
#18
Re: Neck sizing vs Full Length sizing?



<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hazardus</div><div class="ubbcode-body">JFG, Sounds like you have a tighter 308 chamber in this barrel than your last. Should be a bit more accurate but at the expense of reliability.

How I wish the ultimate in accuracy was also the ultimate in reliablity. The damn opposing spectrums are always an annoyance!
wink.gif
</div></div>

Tighter and shorter BTW- I had 200 fire formed Winchester brass that I match prepped for the AW and a load that averaged .465 over 25 5-shot groups. The Winchester wouldn’t even chamber even after being FL resized. I went to a stash of RWS brass and now have to start all over. My overall length has decreased considerably and to now just be at the lands I have to seat the bullet .040 deeper than the factory chamber. I should have left well enough alone, but wanted to use my OPS .30cal on the rifle... Back to the beginning.
 
#19
Re: Neck sizing vs Full Length sizing?

Old wives tail that NS brass is always more accurate. Go to BR central and you will find that well over 50% of the SR BR shooters use FL dies now instead of NS, and 90% of the LR shootes use FL dies. so that pretty well blow away the theory NS is always more accurate.

After 3-4 firings the shoulder will move forward enough the bolt is hard to close. You have two choices then.

1. FL size with a standard FL die or body bump die

2. Throw the brass away and start all over.

Where people get confused with FL sizing 98% of the time is that they do not set up the FL die correctly and bump the shoulders way back instead of only .020 where the cases will fit the chamber and be minimally sized. Most will set the die down to touching the shellholder and push the shoulder way back to even the point of causing a miniscule ridge on the side of the body/shoulder junction where it won't chamber and think it is caused by FL size. NO, improper die adjustment.

BH
 
#20
Re: Neck sizing vs Full Length sizing?

Bounty Hunter, Im glad you mentioned that about not properly adjusting the FL dies as I was about to ask that question. Im using a dillon 550B. I adjusted the fl die per the manual/video which pretty much said if my memory serves me right that to turn it down to touch the shellplate then back off 1/4 turn or so. Cant remember exactly. Anyway does anyone know how I should adjust this to prevent from pushing the shoulder back. And how/what/where do I measure with calipers to make sure the shoulder is sized correctly.
 
#21
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BountyHunter</div><div class="ubbcode-body">Old wives tail that NS brass is always more accurate. Go to BR central and you will find that well over 50% of the SR BR shooters use FL dies now instead of NS, and 90% of the LR shootes use FL dies. so that pretty well blow away the theory NS is always more accurate.

After 3-4 firings the shoulder will move forward enough the bolt is hard to close. You have two choices then.

1. FL size with a standard FL die or body bump die

2. Throw the brass away and start all over.

Where people get confused with FL sizing 98% of the time is that they do not set up the FL die correctly and bump the shoulders way back instead of only .020 where the cases will fit the chamber and be minimally sized. Most will set the die down to touching the shellholder and push the shoulder way back to even the point of causing a miniscule ridge on the side of the body/shoulder junction where it won't chamber and think it is caused by FL size. NO, improper die adjustment.

BH </div></div>

I really appreciate all your guys input.

BH, can you help with the steps I need to follow to make sure I only bump the shoulder back .2000" with a FL die? Currently I have the RCBS 2-die set (FL sizer/deprimer and Bullet sitter).

Another thing... What's the prefer case length? I always thought it was 0.2005", but the Lee Case Length Trimmer takes me only back to 0.2008". Is this good enough?

Thanks again to EVERYONE!!!

Bullitt
 
#22
Re: Neck sizing vs Full Length sizing?

Buy a headspace comparator to fit your calipers, measure your fired brass and adjust your FL die until it gives you a number .002-.003 less than fired.
Try the case in your chamber, if its good mark the die and go to town!

Case length-I trim my 308 to 2.000 and retrim when it reaches 2.015 again (usually lasts a good ling while). I hate case prep.
 
#23
Re: Neck sizing vs Full Length sizing?

Or if you don't have /can't get a headspace comparator, I recently read here that some folks use a .40s&w case to set on the shoulder of the 308 and measure their headspace that way.
 
#24
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BULLITT1668</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BountyHunter</div><div class="ubbcode-body">Old wives tail that NS brass is always more accurate. Go to BR central and you will find that well over 50% of the SR BR shooters use FL dies now instead of NS, and 90% of the LR shootes use FL dies. so that pretty well blow away the theory NS is always more accurate.

After 3-4 firings the shoulder will move forward enough the bolt is hard to close. You have two choices then.

1. FL size with a standard FL die or body bump die

2. Throw the brass away and start all over.

Where people get confused with FL sizing 98% of the time is that they do not set up the FL die correctly and bump the shoulders way back instead of only .020 where the cases will fit the chamber and be minimally sized. Most will set the die down to touching the shellholder and push the shoulder way back to even the point of causing a miniscule ridge on the side of the body/shoulder junction where it won't chamber and think it is caused by FL size. NO, improper die adjustment.

BH </div></div>

I really appreciate all your guys input.

BH, can you help with the steps I need to follow to make sure I only bump the shoulder back .2000" with a FL die? Currently I have the RCBS 2-die set (FL sizer/deprimer and Bullet sitter).

Another thing... What's the prefer case length? I always thought it was 0.2005", but the Lee Case Length Trimmer takes me only back to 0.2008". Is this good enough?

Thanks again to EVERYONE!!!

Bullitt </div></div>


.2000 (a.k.a. .2) isn't the same as .002 - Maybe a typo on your post. If you're pushing the shoulder back .2 that's a bit much. .002 or .003 max is plenty of a bump.
 
#25
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mavrick10_2000</div><div class="ubbcode-body">.2000 (a.k.a. .2) isn't the same as .002 - Maybe a typo on your post. If you're pushing the shoulder back .2 that's a bit much. .002 or .003 max is plenty of a bump.
</div></div>

It was my mistake, but I mean to say .020", as suggested by BountyHunder. Do you recommend I should only bump it .002"?

I guess one of my main questions is that my FL dye is also my de-primer. So, how do it use the FL dye to only bump the case .020" and de-prime my case at the same time?

Thanks,

Bullitt
 
#26
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body">Or if you don't have /can't get a headspace comparator, I recently read here that some folks use a .40s&w case to set on the shoulder of the 308 and measure their headspace that way. </div></div>

Can you please elaborate on this a little more?
 
#27
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BULLITT1668</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body">Or if you don't have /can't get a headspace comparator, I recently read here that some folks use a .40s&w case to set on the shoulder of the 308 and measure their headspace that way. </div></div>

Can you please elaborate on this a little more? </div></div>

Why not, I'm bored. I wouldn't recommend this as a long term fix to not having a good comparator, but it shows what we're talking about (you will be in trouble if you try to bump your shoulder back the .020" you were talking about, we are talking thousandths of an inch here, and as shown, only a few of them at that):
cheapcomp001.jpg
 
#28
Re: Neck sizing vs Full Length sizing?

Lot of good reading here, new things to ponder. I had a strange case with my built Savage. My groups opened up with fire formed brass. I spent one day going through all my targets and trying to figure out why my groups opened up and then it hit me. The early groups that I fired were with brand new brass that I had run through the FL size process to make sure the mouths were round when I went to seat bullets. I FL sized all my brass and my groups went back the way they were. For some reason, my rifle doesn't like Neck sized brass, it prefers FL sized.

As a side note, I use Lapua brass, and it has 7 reloads through it now, the cases aren't cracking, but I have a sneeky suspicion that it's time to anneal the cases.

Branden
 
#29
Re: Neck sizing vs Full Length sizing?

Another way to check if your head space is correct it to take the firing pin assembly out of your bolt and insert a FL sized case into the chamber and close the bolt. You want the bolt to close with just the slightest resistance. Kinda hard to explain really. You will feel the shoulders rub against the chamber. If it is feels real gritty you havent bumped the shoulders back enough. The bolt should almost drop freely all except the last half of the bolt going in the downward position. I am not the best to explain this but i hope your getting the idea. I am sure someone here can elaborate this a bit further. Its a feel thing. You want to feel the case rubbing but just a tinny tinny bit. If the bolt drops down without any resistance you have went to far. Hope this helps some. Lee
 
#30
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BULLITT1668</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mavrick10_2000</div><div class="ubbcode-body">.2000 (a.k.a. .2) isn't the same as .002 - Maybe a typo on your post. If you're pushing the shoulder back .2 that's a bit much. .002 or .003 max is plenty of a bump.</div></div>It was my mistake, but I mean to say .020", as suggested by BountyHunder. Do you recommend I should only bump it .002"?

I guess one of my main questions is that my FL dye is also my de-primer. So, how do it use the FL dye to only bump the case .020" and de-prime my case at the same time?

Thanks,

Bullitt</div></div>.020" is still <span style="font-weight: bold"><span style="text-decoration: underline">10x</span></span> more than you need and will lead to premature case failure. Careful attention to decimal point position is mandatory here.

<span style="font-weight: bold">0.002"</span> is the correct number, two one-thousandths of an inch.<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Dust_Remover</div><div class="ubbcode-body">...For some reason, my rifle doesn't like Neck sized brass, it prefers FL sized.....</div></div>Unless your chamber is <span style="text-decoration: underline">perfectly</span> straight, round and concentric, having a case that fits too closely prevents the cartridge from following the throat and it is forced out of alignment. As pointed out above, most people in search of consistent accuracy will full-length resize.

By only bumping the shoulder back by .002" and letting the F/L dies size the neck to hold the new bullet, we provide ourselves with a cartridge that functions smoothly, ye tis not overworked by excessive sizing.
 
#31
Re: Neck sizing vs Full Length sizing?

I think I"m getting the idea here (and I hope this is also helping others that've had the same questions, but too chicken to ask.JK).

But my main question still remains unanswered... How do it use the FL dye to only bump the case .002" and de-prime my case at the same time?
 
#32
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: E.Shell</div><div class="ubbcode-body">Unless your chamber is <span style="text-decoration: underline">perfectly</span> straight, round and concentric, having a case that fits too closely prevents the cartridge from following the throat and it is forced out of alignment. As pointed out above, most people in search of consistent accuracy will full-length resize.

By only bumping the shoulder back by .002" and letting the F/L dies size the neck to hold the new bullet, we provide ourselves with a cartridge that functions smoothly, ye tis not overworked by excessive sizing. </div></div>

Amen, that's why I made the switch. Any more I only use my neck sizer if I'm in a pinch (found myself with no lube last week) and need rounds.
 
#33
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BULLITT1668</div><div class="ubbcode-body">I think I"m getting the idea here (and I hope this is also helping others that've had the same questions, but too chicken to ask.JK).

But my main question still remains unanswered... How do it use the FL dye to only bump the case .002" and de-prime my case at the same time? </div></div>Refer up a few posts to sobrbiker's excellent instructions to use a .40 S&W case to find a relative shoulder length.

By measuring a case fired in your chamber, you have a *relative* length measurement to begin. "Absolute" length is not important for this operation.

Don't worry about the decapping function for the moment, we must first first set your die to provide a correct shoulder length.


1) Start with a few fired cases of the same manufacture, from your rifle, and measure several. They should be relatively uniform in shoulder length, and if any deviate substantially, remove them from the group.

2) Back your die off a little, lube a case and run it up into the die. While you'll see the neck being sized, your length measurement should not change.

3) Advance the die into the press a little at a time, while checking with your test case. Once contact is made with the shoulder, advance the die a little further until the length measurement is 0.002" shorter that you started with.

Verify this setting by repeating it with another fired case or two.

4) Clean these cases and chamber-check them in your rifle. They should chamber freely, or possibly with a slight feel if the body expanded much.

5) If these cases chamber freely, lock your die in this position. Double check the setting by measuring one more fired case, then size it, verify approximately .002" shoulder length reduction. If this is good, the die is set.

6) Now, set your decapper: Loosen the lock nut on top of the die to allow adjustment of your decapping stem. Carefully run the stem in a little at a time until you are reliably decapping cases as you size. There is about 1/4" latitude in this adjustment, so just set it to knock the old primers out and don't get bogged down trying to find some imaginary perfect spot. Lock your decapper in place and you're finished.
 
#34
Re: Neck sizing vs Full Length sizing?

As mentioned previously FL sizing is preferred by the vast majority of benchrest shooters today. It's important that your handloads ALWAYS chamber perfectly. Not just 4 out of 5 times, or even 9 out of 10 times ..... always.

On the other hand, handloads should be resized to the exact amount for your chamber. Our new Digital Headspace Gauge is designed to show you the exact clearance (at the shoulder) that <span style="font-weight: bold">YOUR</span> handloads will have in <span style="font-weight: bold">YOUR</span> particular chamber. The best feature about this tool is "repeatability" when taking measurements. It's much more reliable than balancing cases on the blade of calipers. When reliability is important, do it right the first time.

- Innovative
 
#36
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Innovative</div><div class="ubbcode-body">....It's much more reliable than balancing cases on the blade of calipers. When reliability is important, do it right the first time.</div></div>While I agree, and this is why I'm a big fan of Mo's direct reading headspace gauge, to suggest a single-rifle reloader make that sort of investment when "balancing" (not so much) provides all the info we need seemed a bit over the top.

RCBS makes a copy of Mo's gauge, but it only renders relative measurements vs Mo's absolute/direct reading device.

BTW, if you're going to sell your stuff here via answering these sorts of threads, maybe you should talk with Frank about helping sponsor the 'Hide like the many other reputable vendors and manufacturers here.
 
#38
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: summitsitter</div><div class="ubbcode-body">I have a question about using the 40SW case has it been fired or sized or does it make a difference? </div></div>
Doesn't matter, as long as the case is round at the mouth and you use the same .40 case for all measurements in the series.

The case sits just about on the shoulder's datum line, and self-aligns as soon as the caliper jaws contact both case heads. A small amount of difference in case diameter (sized vs unsized) only changes the contact point an inconsequential amount.

Since we're just loading this ammo for one rifle, absolute headspace measurement means nothing and we're only concerned with relative measurements. Were we loading this ammo for more than one rifle, we would approach this a little differently, finding the tightest chamber and load for that, and knowing the other gun will give us a little more than optimum stretch.
 
#40
Re: Neck sizing vs Full Length sizing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: skeetlee</div><div class="ubbcode-body">Another way to check if your head space is correct it to take the firing pin assembly out of your bolt and insert a FL sized case into the chamber and close the bolt. You want the bolt to close with just the slightest resistance. Kinda hard to explain really. You will feel the shoulders rub against the chamber. If it is feels real gritty you havent bumped the shoulders back enough. The bolt should almost drop freely all except the last half of the bolt going in the downward position. I am not the best to explain this but i hope your getting the idea. I am sure someone here can elaborate this a bit further. Its a feel thing. You want to feel the case rubbing but just a tinny tinny bit. If the bolt drops down without any resistance you have went to far. Hope this helps some. Lee </div></div>

Why remove the firing pin assembly from the bolt? If your rifle is a cock on open, what difference does it make?
 
#44
Re: Neck sizing vs Full Length sizing?

Of course I did. I was just wondering how many people have a cock-on-close action. About the only one I know of is the SMLE, maybe it was more popular than I remembered.

BTW, I totally agree with your overall recommendation, I just don't think it's important to remove the firing pin.
 
#45
Re: Neck sizing vs Full Length sizing?

Since very few of us are running cock-on-close style rifles for the precision work most of us here strive for, this might not be an issue in the context of this forum.

As far as removing the striker assembly in modern design rifles, this IS necessary IF we are to actually feel the fit of the brass, or, when we use a headspace gauge.

There is a huge difference in feel between an empty bolt body and an assembled bolt. If we set our sizer for a slight feel with a stripped bolt, we will not be able to detect the same fit at all with the striker in place. Removal of the striker assembly takes about 5 seconds on most modern rifles, you could try it and easily demonstrate this for yourself.

Many folks do things differently and good results can indeed be achieved by a careful touch, but I personally prefer the non-subjective method of measurement as outlined above or with a precision gauge.
 
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