Okay, so what's the deal with the "revolutionary discovery" that full length sizing is unquestionably better for accuracy than neck sizing?
(referencing a video online interviewing a who's who of F-class shooters unanimously in favor of Full Length sizing).

I am a reloader of 50 years experience. I gravitate toward techniques that have proven themselves to me, and try to avoid techniques that "get into the weeds", favoring practicality of methods.
Neck sizing or partial sizing in an FL die has shown me documentable advantage (I document nearly every round/group fired on target along with chrono readings).

The recent contention for full length sizing seems almost rabid. Not even a step away from claiming neck sizing has been an Emperor Without Clothes all along, and neck sizing dies are a waste of money and should be thrown away.

Can someone recently encountering this, and/or "making the transition" explain what is going on here? Are these decorated competition shooters "hiding" something when they advocate Full Length Sizing? Is it not truly "Full Length Sizing" as is commonly understood? (Full travel of ram to shellholder cam-over.) I see some in the video adding "two thousandths!" (shoulder bump) to their advocacy, indicating not your garden-variety Joe Six Pack full sizing in a common market die.

What "revolutionary discovery" renders all the neck sizing and partial sizing done (and equipment sold for such) for decades now all a falsehood?

I don't think it's that FL sizing is more accurate than Neck sizing, but rather that FL sizing isn't less accurate than Neck sizing and is generally more reliable for their type of shooting.

I routinely set garden variety FL dies to produce two or three thousandths shoulder setback. While this doesn't size the case as much as the die may be capable of doing, it does size the entirety of the case and so is full length sizing. It's just not full length sizing more than necessary.

It appears you've wound yourself up into a state of righteous indignation or the like over terminology.

Some of these champions were also bench rest shooters. Still advocating "full length resizing". As I suspected, they are probably NOT advocating it as the term is commonly understood.

https://www.youtube.com/watch?v=vaqg4sJvg24

I've spent 50 years listening to.people argue this same question and have only a couple of things to say about it. If you only have 1 (one) gun chambered for said cartridge do whatever trips your trigger and gives you the results you want. If you have more than 1 (one) gun chambered for the same cartridge you are short sighted fool to resize them differently for each gun. Size them SO THEY WILL WORK IN ANY GUN OF THE SAME CHAMBERING you have. Murphy is hard at work when you are getting your stuff together for a hunt with lots of things on your mind and even worse if you are also organizing for a woman or kid also. Don't get ANAL ABOUT YOUR RELIABILITY of your ammo to function correctly every single time. You asked. I have spoken from experience. Mb

It’s mainly that FL sizing is more consistent shot to shot than neck sizing. Brass doesn’t always blow out exactly the same and the fact that these guys quite often use just enough neck tension to hold a bullet, then finish seating with bolt closure in other words a predictable jam, so it’s the feel of bolt closure.

Secondly I do wish people would realize that the guns they are using have absolutely nothing in common with a factory hunting rifle unles you go hunting with a 4000 dollar gun with a 3000 dollar scope on it. Sitting on top of a 1000 dollar rest. Special built for just one purpose. Tiny groups.

Hunting rifles I FL size always for feeding reliability. Varmint rifles get both NS for 4 firings FL to bump the shoulder plus anneal on the 5th because I don’t really care about reliability since most of my varmint rifles are single shot. AR get FL every time again for reliability reasons.
My bench guns got FL due to the reasons stated above in paragraph 1.

Do what you want for the situation and whatever works best for you. There isn’t a one size fits all here.

I would contend that that it is proper full length sizing.

I generally try for no more than 1 thou set back on the shoulder, but then I have dedicated brass for every gun.

Are you a short sighted fool?

And ignorant.....

Agree that the 1-2 thousands bump was previously called partial sizing. From early on I avoided the full cam over bubba sizing.

As has already been pointed out sizing slightly every time produces better consistency and feeding. I also think the slight amount of brass working is better long term than neck sizing only and then doing a more major FL sizing every 5 shots or so. Also as oointed out previously hard to document a real difference between the two methods as far as hunting rifle accuracy. I think I am getting a real improvement in case life by treating the cases the same way each loading and annealing about every fourth or fifth time. I use a lee collet die and either a bump die or a FL die with the expander removed.

I too try for about a .002 shoulder bump. If I am not too cheap and can find the dies I want, I like to get a full length bushing die so I can also control neck tension to suit my wants and needs.
I too have several years of reloading under my belt, but I am always looking to learn and change if a better way comes along.

Think everyone covered this topic very well. I size for the chambers I have to work with. That may mean setting my die up differently than every body else. If something works for you, it works.

I would like a more detailed explanation of the FL sizing techniques being advocated, and a description of the equipment employed. I won't just swallow that advice and use plain-jane RCBS full-length sizing dies with full cam over. The brass they're using, and how they're prepping it might matter too.

I'm a big fan of neck sizing, and I do run rifle specific brass. It makes supremely accurate hunting ammo. Brass seems to last longer, and you don't have to mess with the lube BS. My runout numbers decreased very nicely by neck sizing only. When brass does become a bit too snug, I'll bump shoulders back .002 but that usually doesn't happen until 4-5 loadings.

Those videos are misleading. The guy behind them actually partial fl sizes, bumping his shoulders two or three thousandths. But he calls it fl sizing. And now an entire generation of millenial shooters is going around convinced that the only real way to reload is to fl size. I suspect quite a few of them may not realize the guy is only bumping his shoulders.

+1

If you squeeze a case .002- .003 smaller at the web and dia. of the shoulder, bump the shoulder back .002 and reduce neck to .002 under bullet dia. why isn't that FL sizing.

Neck size (per gun), turn bottlenecks, anneal, load x times, full size.

Repeat.

lol......

I've owned up to seven different 270's at the same time, each with their own brand/lot of brass, some with their own dedicated dies. I've never been able to get optimum accuracy when I tried to make them all dance to the same tune at the same time........

Like some of the others I make a distinction between FL vs PFLR. Despite owning plenty of LCD's I still PFLR for a few of my rifles.

It is.

Years ago (read: decades) the notion of partial full length resizing was to back off a FLR die a few turns to only size the neck and not bump the shoulder back thereby approximating the function of a dedicated neck sizing die. The problem with this was that often the FLR die (backed off a turn or two) would still squeeze the base a bit and move the shoulder forward enough to make the round difficult to chamber. The looser your rifle's chamber, the worse the "problem" would be.

I find this a ever fascinating topic!

Seems so much to learn and consider.

I understand the need to get the ammo to feed, chamber , and go boom! ( most important)

How " accurate" or tight the groups are should be self explanatory. Kinda like a golf score.....you know what you got,
So why the need to expound on others perceived follies! As in they know what they got....hopefully they are happy, or open to suggestions.

Get a Lee Ultimate die set and a Redding body die.

Thank me later.

Partial sizing is FL sizing. What it does is resize the case to fit the rifle chamber the case was fired in! There are min size and max size that work in rifle chamber's.Do a couple neck sizes with an FL die and you probably won't get it to chamber again. At that point start moving the sizing die down a bit at a time till the case will chamber easily. before that point you'll find you can chamber the case but you'll also feel a rub. That's from the shoulder not being pushed back quite enough And it's rubbing in the chamber, close but for me not close enough. Some guy's like to feel the shoulder rub!

The debate is really just about whether "FL sizing" refers to returning the brass case to have clearance in the chamber in question, or to SAAMI dimensions. The die adjustment description in the instructions of most manufacturer's FL die sets corresponds to returning the case to SAAMI dimensions, but I can understand the other side of the argument, as well.

I've never had a die i could back off a full turn that would go from bumping the shoulder back .002 and then back a full turn and still size the web.

FL sizing is when we set up a conventional die according to instructions where the press is on the verge of camming over or fully camming over. PFLR is backing the die off and sizing the case, but not sizing it fully to the die's ability. Sizing to SAMMI specs usually requires a small base die.

I guess I “ Bubba” size my brass. I have five 7mags, multiple 264’s, 308’s, 270 WSM’s 30-06’s. I have no problem getting sub inch loads. There is no way I could keep all of those separate. Multiple Creeds, 223’s, 270’s, probably more I can’t remember. Couple 300 Win mags, two 6.5-06’s. I’d have to have a lot more space for loaded Ammo too. Maybe if I had a target rifle, I’d neck size.

Since this thread is BIG GAME RIFLES the answer is simple.

ALL hunting ammo should be loaded into fully prepped NEW cases. That means FL sized, trimmed, uniformed and deburred pockets and chamfered necks.

OR you can buy Nosler brass and FL size it.

An ammo failure can ruin a hunt or worse.

I disagree. I prefer my hunting handloads to be in once fired brass. Prepped of course. It has been proofed that way.

Hmm, so what do you do with the brass once it's been fired? Do you throw it away? I mean, I'll be happy to take it off your hands. Even pay the shipping........

Just to fan the flames I don't consider brass to be completely fire formed until the second loading and in severe cases the third. Don't see it anymore but some custom die makers wanted to work with twice fired brass to make the dies from.

I would only do the hard full length sizing for autos and lever guns. The FL bump and either the Lee Collet or a bushing die is where it's at for me for hunting loads.

Are you sure they were not advocating for the "other" guy to full length size? I have a 243 that is super accurate when I neck size it. It shoots very well with full length sized brass barely bumping the shoulder back. If the rifle has a large chamber brass will last longer and it will probably shoot better with neck sized brass.

That is probably a good time to anneal also. All the ammo I load is marked to show what rifle it is loaded for.

Well far be it from me to disagree with guys with 24 and 35 thousand posts.

When I'm HUNTING I'm not picking up brass so there is no "after".

There are many people who have even figured out that it is difficult, for HUNTING, to load better ammo than premium factory made.

Buy a super accurate 6.5 CM and try and do better than Hornady ELD PH ammo. My Tikka puts 3 in a dime.

35 posts or 35 thousand doesn't matter. We're talking about handloads here, not factory, and I stated why I do what I do. That is all.

No need to come on strong with a "final word" type statement and get your back up when someone disagrees with you over a technical point.

I can't count the number of arguments you could have just by uttering those words. Probably lose about 80% of em too.

The bullshit is running really deep in this thread

"Yeah, I meter my charges using one of the ol' lady's teaspoons...how 'bout you, Sam?"

"Me too. Dave, how do you do it?"

"Yup, same. Teaspoon method here. How are you charging, George?"

"Teaspoon, just like all the rest o you knuckleheads. Gave my Sartorius to the wife to use in the kitchen. She's made some fantastic donuts using that thing."

"Donuts?"

"Aw hell...just another internet myth. Donuts don't bother me none."

Hah!

I wonder, are you saying that reloads are not to the level of quality of Nosler factory ammo or similar? Well I have shot some pretty good factory ammo. For most hunting the cheapo stuff from Winchester or Federal will get the job done. That said in the last 45 years which is some 4 years after I started reloading I have used reloads for 98% of all my hunting. I can absolutely say that good factory brass that has been fired 4 times or so and loaded properly is every bit as good as any factory load brass. It fits my chamber perfectly, I have shot groups with those cases and know none of them has any issues. I have had issues with factory ammo. Remington misfires, poorly made brass. Federal with brass so soft it looked like a proof load was fired in it. Winchester oddly has always been pretty good to me. Mostly I shoot factory ammo up for the brass. Sometime I would just pull the bullet and save the powder only to load the factory brass with something I wanted to shoot out of it. I have had problems with Hornady ammo not being accurate in my 257. I consider Hornady brass at the lower end of acceptable. As for accuracy I will accept at the most MOA in my hunting ammo for big game. Better does not always just mean accuracy. When I started loading ammo there were no factory rounds topped with partitions out there. Factory ammo in general was good if it shot into 1 1/2 to 2 inches. Sure if I only shot 40 rounds a year I would probably shoot factory ammo but the reality is I burn at least 1200 on a slow year.

Neck sized for about 40 years for all manner of cartridges and have never had to bump shoulders. If it came out of a chamber, it always goes back in. All cartridges, however, are rifle specific. Once had a pair of 270's and a cartridge cross over could go one way but not the other.

This is how I do it too in addition to I guess 98% full length sizing (die just backed off very slightly to offset the case stretch with the web resizing by bumping the shoulder back a very slight amount. I’ve recently started to anneal more regularly as well. Works great for me ymmv.

For every round I send after a big game critter, I may shoot a 100rounds at the range. I pick up my precious brass. This year I killed 2 bulls and 2 pronghorns, and by golly found all the brass laying on the ground.

Don’t own a CM, but I’ve yet to find factory ammo loaded with a suitable big game bullet (especially a suitable elk bullet) that I can’t beat with my handloads.

Somewhere in the world such ammo might exist......

I never allow my brass to hit the ground. Head thing with me!

This is where I'm at. "Partially sizing" for 6 .250 Savages here. I DO keep my brass separate for each one. Three .270's. Same deal. Multiple .22 centerfires (even in same caliber) likewise.

I DO FL size for the 4 .30-30's here, and do not dedicate brass to a gun. Reasons should be self evident.

My great concern with this video was that someone just getting into reloading will take the misunderstanding conveyed (cultivated, actually) in the film that shoving that brass all the way into a die every single time is the gospel now for accuracy.

Most here have learned that is NOT true,

I appreciate all the participation in this "firestorm" I did not expect!

I have always FL sized with the cam over method as the die instructions taught when I started reloading 30+ years ago.
I am able to get most hunting rifles to shoot well under 1 inch groups and most into 1/2 inch groups.
I only neck size in my 300 win mag because when I got it close to 30 years ago my uncle who shot magnum rifles told me to.
I have never FL sized that brass and I can't even guess how many loadings it has.
Just how I do it and it has worked very well for me.

+1, but - read about Mule Deer setting the dies to leave just a slight 'smash fit' and did that for a few years. Lately I started watching the Youtube videos from Eric Cortina and have now switched to a slight bump. To be honest, both worked just fine and I can't shoot good enough to tell any difference. I'm still going with the slight setback .002-.003 as they to chamber easy and always and accuracy is good.

I’m going with the world champions advice.. Besides I been full length sizing since I started reloading 25 years ago..

So we can expect you at the next F class shoot?

So the same BS video about the pros has to be posted twice. How many on this forum go to the regional, national and world championship BR matches and place in the top 20? How about top 30? Top 50?

No BR matches but i do participate in NRA and CMP sanction mid range prone/high power shoots. Along with NRA regionals mid range up here. I missed last yrs 800,900,1000 NRA sanctioned match.

I neck size for all my rifles (mostly factory chambered) using bushing neck dies. When I feel resistance on a case they get a shoulder bump to feed like butter again. Spoke with Whidden yesterday about a die for my 25 BR Ackley and the dies they make are set up to minimize touching the base of the case. I guess you could say they are PFL instead of Fl.
GreggH

I learned decades ago what applies to BR shooting with minimum spec'ed BR rifles and the loads they use doesn't necessarily apply to a factory style hunting rifle and hunting loads.

Although competition improves the breed, I know better than to put Goodyear racing slicks on my 3/4 ton pickup.............

I didn't see where anyone here asked about bench rest shooting, yet several of you keep referring to it.
Eric Cortina, who made the video, is a Lapua team F Class and PRS shooter.
Nobody ask about loading for bench rest.

Sigh.......
You’re being kind’ of literal here.

F-Class, BR, etc.........

What crock of schit! Those are some of the best shooters/ smiths in the country, so i'll take there advice all day long over someone with a $20 Lee die set. Hopefully the newbies DO see it, and understand it's most certainly the best way to size your brass period. Why size your brass 3 to 5 times one way, and then have to FL size to get it to fit RIGHT again? I want uniform everything... everything the same everytime!

What a crock........period.

Neck sizing with a good die will most of the time produce less neck runout than conventional FL sizing dies for our hunting or varmint rifles.

The BR shooters (and most other of the competitive shooters) are using Wilson style dies cut with the same reamer as their custom, lapped, minimum spec chambered barrels.

Do you have barrels and dies that are reamed to minimum specs?

Competition improves the breed, but attempting to mimic some parts of the competitive shooters regime while not doing everything else is like putting a wing on our pickup and expecting to compete in the Indy 500........

I can make as good or better accuracy by making straighter necks by Nk sizing with a LCD or conventional Nk die--no lube, no stretch, no trimming--and make brass last exponentially longer than when FL sizing for my hunting and varmint rifles.

There is a difference between pushing the shoulder back and FL sizing.

Please explain the difference.

So much wrong thinking in that post if accuracy is your goal. Bullshcit on the the most BR shooters using a custom cut Wilson die to size. The reasoning behind that is guys using a custom reamer to shorten or lengthen the body or neck on a proven cartridge in an effort to create a better mouse trap. The Wilson die you referenced is in fact a neck die. What kind of concentricity gauge are you using to measure runout? Most guys who own one will tell you it's collecting dust. Any shooter worth his salt will tell you that as long as your runnout is .003 or less you'll be hard pressed to see it on paper. Those same winning BR shooters are far more likely using Redding bushing dies to size cases, and almost everytime a runout problem is discussed on a BR forum the word bushing is involved.
I've won my fair share of local factory gun BR matches including 6 in a row, and there wasn't a neck die used to do it . Pony up for Forster FL dies and move on. You can even have them hone the neck out to your specs allowing you to work the brass less. I'm done arguing about this though, as I know neck dies will still have that hardheaded following. I'll take the advice of someone who has shot 1,000's of precision rds a yr every yr vs the average Joe who fires 1-200 shots thru his hunting rifles a yr. The best part is we are free to choose whichever we want.

Pushing the shoulder back via a FL die (PFLR) or a body die will indeed partially size the case body--how much is generally determined by how far we push the shoulder back. Sizing with a FL die and almost camming over or fully camming over will size the body almost all the way to the web.

Grovey,
BS.

How can they know their RO is .003 or less if their concentricity gauge is collecting dust?

If you like to induce RO by all means use a bushing die. Not all the competitive shooters are using bushing dies. If somebody wants to make accurate hunting ammo I suggest staying away from bushing dies.

I own more Forster dies than you. Redding sizing dies usually make straighter hunting brass than Forster. Forster seater dies usually seat bullets straighter than Redding seaters. The LCD die beats or least matches the other dies, and does it with less effort.

I'll take the advice of somebody who shoots lowly factory rifles or simple custom bbl hunting rifles over the different discipline of competitive shooting with custom rifles and loads built for competition.

I've owned and shot in local (very local) matches with a Stolle action 22PPC. I understand the difference between a hunting rifle and loads, and competition rifle and loads. Some people are always willing to conflate the two.

hunting ammo should be full length resized and yes there are reasons ,the main reason safety. now target ammo is it for just range shooting ? or competition ? for range shooting both works fine. the best bench rest competition shooters full length resize ,so what does that tell you ?

Come on, man!

I can’t remember the last time I FL sized brass for any of my hunting rifles.........

The chambers in factory rifles are generally so oversized even NK sized brass can sometimes be interchanged between rifles.

Nothing

First time or two I neck size with FL die. After that I FL Size and make the case's fit the chamber they go in. I think this bump the shoulder and Partial sizing discription confuse a lot of people. I use partial but I think some people just don't get it. You cannot bump a shoulder without sizing the whole case to some degree! If you could the base of the shoulder would roll out a bit and you probably couldn't chamber the round again without FL sizing again. Setting up the FL die as directions say to do, re-size's the case to SAMMI spec so that the case will work in every rifle of that cartridge. Partial sizing size's the case to fit a particular chamber only. Then it could go to SAMMI max or if you have a headspace problem, simply match the chamber! Bumping the shoulder simply is nothing more than partial sizing. Many people feel the need to use cute catch words to describe a process, bumping the shoulder is one of them. You can neck size with a FL die but move the shoulder at all and neck sizing ends and you are full length sizing at that point. I'm pretty sure if manufacturer's didn't say to adjust the dies the way they do there would be law suits sooner or later for guy's screwing it up. So the safe way t have people adjust the dies is to SAMMI min spec and make the case fit in all chamber's for that cartridge!

I recall an article by Seyfried about ammo “when it must work (or go bang)”. He mentioned only using fired brass since it has truly been proven. If it’s new and has a flaw that might be found only when it’s fired for the first time.

There is no danger presented when you cannot chamber a cartridge because it needs a shoulder bump or body sizing. Inconvenience, yes...bit no danger (unless you're facing a critter than can eat or trample you). Bottom line: the less you have to reduce the dimensions of a fired case to reload it and make it functional again, the better. And straight necks matter. OTOH, a case reduced in dimensions too much CAN be dangerous.

Your stuck using 1950's tech, and it seems you always will be. We both know there is more than one way of getting this done, so we'll have agree to disagree. In the end as long as I'm not setting beside them at the range I honestly don't care how someone else reloads. However...I don't like to see someone spread the same old 50+ yr BS on a forum about the merits of neck sizing. But......You skin your cat your way, and I'll skin mine my way. My way just happens to be the way that the best shooters on the planet get it done. I'm ok with that vs some random dude touting his reloading prowess.

Some smart people thought the world was flat once upon a time. Things change. One night while going down an internet rabbit hole I found a research paper done where they fired several thousand rounds from a shooting machine. Full length sized,partial full length sized and neck sized. The full length sized rounds were more accurate. I wish I had saved a link. Truth is the target guys have proved it’s more consistent and more accurate. Thats why they do it. The other reason people neck size is to extend brass life. Properly ,key word properly, full length resized brass will last just as long. The other reason they fls is f class is a timed event. Having rounds that wont chamber or chamber hard can cost time on the shooting line. For a hunter who is outdoors in sometimes harsh conditions fls will ensure your brass always chambers. There really is no reason to neck size only other than that is they way you've always done it. If it works for you fine. But truth is truth. The earth is not flat and neck sizing is not better than fls your brass.

My experience says neck sizing makes more accurate loads than my FL sizing experiments. I've only been loading ammo since 1985, and neck sizing for about 15 years though. BTW, the best way to make sure brass fits is to run it through your rifle after neck sizing.....it really isn't that hard to make accurate, foolproof, safe ammo.

Not real hard to tell who's actually resized and reuse the same pieces of brass multiple times and I don't mean five or six by multiple I'm talking 15 to 20.

Neck size for all my bolt guns until they become a little harder to chamber then a full length, then back to neck sizing. Just dip the case neck in graphite powder and size. Full length is a PITA with case lube and I avoid it if I can. I do full length size for my Number 1s though. This is for hunting rifles not benchrest. To tell the truth I don't really care if my rifles shoot 1/2 inch, 3/4 inch or 1 inch, or even a bit larger. If I full length sized and got 1/2 inch groups and neck sized and got 1 inch groups i'd still neck size because in the hunting field it doesn't matter for me. I'd rather spend time out hunting in the bush than at the range trying to shave 1/4 inch off my group size.

Very interesting reading.Guess I've been doing it all wrong for the past 40 years or so, as I always full length rezized my cases.

I do not use NK dies for anything period. Growing up in Western Kansas in the 60's shooting prairie dogs, I owned three varmint rifles, 222, 22-250, and a 243. The 22-250 was custom built, the other two were factory rifles. I could notice at that time that NK sizing was not nearly as accurate as FL. Later on I purchased run out tools and it proved to me that NK cases have far more run out. I only bump the shoulder back .002 or .003 and use a bushing die.

On the other hand, on my hunting rifles I take for big game I full length size all of my cases as I don't want to have any chambering problem when hunting Deer and Elk.

Boy, this sure went to schitt in a hurry!

FWIW, I read about partial full-length sizing years ago, and have always sized just enough that my brass chambers with little or no effort. That’s always been accomplished before the die runs hard into the shellholder. When I began buying new brass instead of just refilling my factory ammo cases, I used the same setting, but now I usually just run the case over the expander to round it out. Some cartridges may get sized in a Lee collet die. I have case gauges for everything I load, and new brass just falls into them. Some of my PFLS cases go in all the way, but a few don’t quite. Mostly, I’m checking to make sure none are too short, headspace-wise, or too long in the neck, which would require trimming. With the case in the gauge base-down on the bench, I run a machinist’s pocket ruler across the top; if it catches, the case is too long. Cases that don’t go all the way in get checked for length with a caliper set as a snap-gauge.

What I do works for me, my ammo shoots well, and I’ve yet to blow anything up. Don’t use pick-up brass, except for setting up dies and dummy rounds. Don’t anneal yet, as four firings is all I’ve asked of any of my brass so far, but if the nonsense continues, who knows? I have plenty right now, probably enough to use up all my primers and bullets, and maybe a barrel or two. In normal times brass is reasonably cheap, so I don’t worry about squeezing more loadings out of it like some do.

I buy FL dies, I think I own one neck size die that came in a 3 die set I bought used.

Mike

[quote=WEL]Some smart people thought the world was flat once upon a time. Things change. One night while going down an internet rabbit hole I found a research paper done where they fired several thousand rounds from a shooting machine. Full length sized,partial full length sized and neck sized. The full length sized rounds were more accurate. I wish I had saved a link. Truth is the target guys have proved it’s more consistent and more accurate. Thats why they do it. The other reason people neck size is to extend brass life. Properly ,key word properly, full length resized brass will last just as long. The other reason they fls is f class is a timed event. Having rounds that wont chamber or chamber hard can cost time on the shooting line. For a hunter who is outdoors in sometimes harsh conditions fls will ensure your brass always chambers. There really is no reason to neck size only other than that is they way you've always done it. If it works for you fine. But truth is truth. The earth is not flat and neck sizing is not better than fls your brass. [/quote

^^^THIS ^^^ very true thanks for posting this,Pete53

My best old-fart guess is that it’s pretty much dependent on a number of factors, and one test proves nothing, except perhaps for that barrel. I think that presenting the bullet to the rifling as straight and centered as possible is the goal, and getting there may be accomplished in different ways with different barrels. It’s probably easier in match-grade chambers.