Full length or neck only resizing

I have always done full length resizing of my brass. I am thinking of going with neck only for one particular caliber that I only have one rife for.

If I do just neck size is there a recommended number of times I do that before I need to do a full length resizing?

Any advice would be much appreciated.

Just do a shoulder bump of .003" and call it good. The neck only sizing may work for you for one sizing, but you will certainly have chambering issues after 1 or 2 only neck sizings. I used to neck size my 300 WM competition ammo, until I had major chambering problems. In theory, neck sizing should work forever, since the round was fired in your chamber and should have a perfect fit. In reality, the brass case swells ever so slightly and can change it's shape slightly during neck sizing or the loading process.

If you want to keep it simple, just FL size it.

Bump the shoulder enough to chamber.

Shoulder bump .002"-.003" for bolt action.

Ive still never had any issue with neck sizing when only using in the gun the cases were fire formed in.

I've seen several with the case stuck after firing. The dreaded, butt on the ground, and boot stomping on the bolt handle is not a pretty sight.

I would think that is from something unrelated to neck sizing, perhaps too warm a load?

Seen it happen to about four rifles that have had brass neck sized. I know one was just a 25-06 hunting rifle. I asked his charge, and he showed me. Easily below book max.

Firing brass makes it flow forward. We all know that. We see case lengths change after firing. It makes complete sense to me how it is bound to happen, with neck sizing only.

Agreed. I've been neck sizing only for the past 4 years for my 7mag, 243, and 7-08. Haven't had to bump shoulders yet, and have no extraction or feeding issues. Love the fact that no lube is required.

I'm reading two opposing cases for Neck sizing. So I think I will stick to FL sizing since I have not had any issues in the past with that.

Why not give it a try? If you run into problems then stop.

I would have to invest in the dies and from what I hear it may not be worth the trouble

Can you not adjust the dies to just bump the shoulder?

Setting up a FL die to bump the shoulder is perfectly acceptable. It works.

I changed over the Lee collet dies for neck sizing some time back. The advantages are having no expander button to pull your neck out of alignment and (the biggie!) not having to use case lube. And, you just can't get a straighter case neck. I HAVE had to bump shoulders back, though. To me that's no big deal.

I neck sized 300 WM (I did this a lot for this caliber) and some 260 Rem. I quickly realized neck sizing was not for me. If you fire your round and stick it back in the ammo box it came out of, it may work. I would generally have to go find my brass off the ground after I fired in a comp. Often times a neck size only case would have tight chambering, or chambering where I had to force the bolt closed, and this would be in the middle of a stage in a comp. I didn't like this at all. I need 100% reliable and smooth chambering. A partial shoulder bump works well. But I still chamber check most of my brass after sizing when doing a shoulder bump, to insure 100% smooth chambering. Most of my personal ammo I FL size- 308 Win, 270 Win, 300 blk out, 223. I'll shoulder bump my 6.5x47 Lapua and 300 WM and 7mm/300 WM ammo. This works fine, but it does take more time to set up the sizing die to get it just right.

I won't even neck size customer ammo any more. I have done several neck sizing projects and the ammo came back to me for tight chambering or not chambering at all. It does happen, and is very common for neck only sizing. I won't do it for this reason.

Why not just bump shoulders .002" and know you're never going to have a problem?

Ammo with bumped shoulders shoots just as tight, but it is reliable to chamber and eject.

This is a silly argument.

Yeah, I don’t get this at all.

It really depends too on the caliber. I have used Lee Collet Dies to size 17 Remington and 221Fireball brass until it was wore out with loose pockets or split necks and never Full length sized.
I noted that my 17 Rem brass usually gave out at 9 reloads. 221 brass is like the energizer bunny it just keeps on going.

I got a Lee collet die just to try neck sizing and actually got better accuracy by using a Hornady bushing die and bumping .002".

Also, about 10% of my once-fired brass required a bit of extra force to chamber than factory ammo or brass that had the shoulder bumped.

I know lots of folks neck size, but I tried it and it didn't have any benefit to me.

If anyone is interested, I'll sell you my Lee collet 6.5 creedmoor die on the cheap.

It depends on the gun. I have a rifle that will seize up something fierce if I bump the shoulder back in the slightest. Once I figured out that I shouldn’t bump, it was cycling easy again.

What cartridge?

Ten, What cartridge and what rifle?

Steve, I would say give it a go. You will learn more about reloading by doing it. Most all of us have tried to just neck sized at some point. For what it's worth I do a partial full length to set shoulders back on my
bolt guns .001-.002. Semi autos, levers or pumps get full sized.

I think every loader should try everything from full length sizing that will fit any rifle, to only bumping shoulders a few thousandths to fit a specific chamber. They should size brass for a "crush fit" in a specific chamber, and also neck size for a few rifles. After you do that you will size your brass the way you want it and know why you do it. Don't overthink it and take everything you read on the internet with a grain of salt. Reloading is not very complicated.

I cringe at the thought of this. What would be the advantage of neck only? I read up higher something about aligned necks. I did not realize sizing with a .002 push to the shoulder was knocking my necks out of center. I'm just not seeing what's to be gained by this.

Does that mean that any new brass that hasn't expanded to your chamber gets stuck as well?

That's my point, there is no gain by neck sizing. Guys doing it are just being stubborn in my opinion. "It's the way I've always done it" mentality. Pretty sure Judd said even bench rest guys got away from neck sizing.

I'm sorry but you cant have your cake and eat it too. If bumping .002 is better than FL size then as long as neck sized chambers and functions it is that much better than bumped .002.

I feel relatively certain we couldn't prove much difference between FL all the way to neck sized by accuracy alone so long as all is consistand in your process you should achieve a very similar end. Makes me wonder for the ones who have theirs jam and get stuck if there is something out of whack with their camber?

I will buy the dies if you're serious. Shoot me a PM.

Just curious if you checked your runout numbers after using the Lee, as compared to FL sizer? My runout numbers were way better with neck sizing only.

Neck sizing only will increase brass life (less stretch going forward, no lube to deal with, and your runout will likely be decreased. It's not just being stubborn, as someone mistakenly mentioned. I could see needing to bump back shoulders if you're switching fire formed brass between a couple of different rifles, but not so for one specific rifle.

I get very little runout (.002ish) fl sizing.

That's where my NS numbers are. I was using RCBS dies, but FL sizing gave me .003-.006 variances.

Some of the old school guys still do only neck size but even then they all own a body die and will need to use it occasionally. Almost all the long range benchrest and Fclass guys use FL dies.

Couple of years ago I decided to try various ways of resizing for my 223 to see what would work best for accuracy. I went with my favorite load, which was H335 behind a 40 gr Nosler BT, and CCI BR4 primers. I loaded and shot a serious bunch of reloads and resized with:
Lee Collet Die
RCBS FL Die
Redding Neck Die
Redding FL type S Bushing Die.
I shot 10 shot groups, and plenty of them. Started with once fired brass. Cleaned the bore between Die changes. Nosler brass.

When the smoke all blew away, Neck Sizing came in last. The Bushing Die was better, but not best. The Collet Die was best, with the Partial FL Sizing about the same. The Collet Die is by far the easiest to use, and if you shoot mild loads, i’d sure buy one of those. But...I shoot warm loads and found that I had chambering problems eventually. So I finally decided to go with Partial FL Resizing as my standard method.

I will not say that my test is the definitive test of dies and accuracy. Maybe a better shooter and better reload techniques and different Die manufacturers would have had a different result, but I came away from all that shooting being convinced that the Partial FL Resizing was the way to go. And that means using the FL Die to bump the case shoulder back after firing, and that amount of sizing will vary with your rifle chamber dimensions.

The one sizing method I did not try, and I wish I had, was to bump the shoulder with a Body Die and then use the Collet Die on the case neck. That might actually be the way to go, though it adds one more step in the reload process.

.002" bump is not over working brass. Primer pockets will go bad before anything else.

A boot to the bolt handle has to be seen in order to be believable for some people I guess.

Gunsmiths are happy to charge to install a new handle, in the event one breaks off.

Some cases work well for neck sizing and you don't see the issues that other rounds have when neck sizing. Neck sizing works. But there are draw backs to doing it, which we have stated. The good thing about loading your own ammo is you can prep and size your brass in a method that works for you.

I've witnessed 6.5x47L cases with 25+ loads on them and only getting fl sized with minimal bump.

Gotta love that little primer pocket

This is what works for me. I will say that the only volume loading I have done is for .222 and .223, so I still don't know about '06 class cartridges...I will be finding out about them eventually. But so far I have found that I can neck size only for about three loadings using the collet dies, then use of the body die needs to be put to work.

I anneal about every other or third loading also. That might be part of the equation.

6.8 spec II.

Any idea what causes that?

What is the proper technique for bumping the shoulder back, and how do you measure how much you have bumped it? Special measuring tools required? thanks

It can be done simply by feel with a bolt action. It can be tedious, but it works.

If you want to go by measurements, a bullet comparator that fits near the midpoint of the shoulder will work.

Hornady and sinclair makes a tool it looks like the tool made for measuring oal off the ogive but measures off the shoulder. Bump .001-.002 anything over is overworking the brass.

Turning your sizing die in by 6 degrees pushes the shoulder down by about 0.001 inch. If I've done my arithmetic correctly.

so you would put a case in the press, raise it to the high point. Then screw the FL die down to where it contacts the case. Then turn the die and additional 6 degrees?

It was posted on here not long ago you could use a sized pistol case such as a 9mm and a caliper to measure also.

https://www.hornady.com/reloading/precis...llet-comparator

Wish it was that easy. Screw your die in until it contacts the shell holder, then back it out about tenth of a turn. Size a case and measure. Keep turning the die in a few degrees at a time. It's a trial-and-error proposition.

Be sure and measure a fired case first, though.

You've posted those numbers for years, and damned if I never can remember them.

Trail and error...

Me three. Had to figure it out all over again. The formula is 1 divided by 14 divided by 360.

I can go with you on that math.

Wait, I know there's 14 tpi, but it does not use up 14 threads to make one full rev. What am I missing?

One turn, 360 degrees, moves the die up or down 1/14 inch.

If it chambers perfectly, is there a need to bump back. 001-.002"? I always bump back .001-.002" anyway after measuring my fired brass. It's just a thought.

Unless your loads are on the extreme soft side at some point you'll have to bump.

Got it!

Than you sir.

From the website:

“ Our Bullet Comparator measures rounds from the ogive to provide consistent, precise measurements. You can also use it to check uniformity of bullets from base to ogive.”

Ok, call me stupid. But this appears to be an instrument to measure bullet seating vis a vis the lands. I guess it can also be used to measure to the mid point of the shoulder?

Use the .30 insert on a .223 case, for instance.

sorry, my error, try this

https://www.cabelas.com/product/Hornady-...mp;gclsrc=aw.ds

Ok here is old school. Ink or smoke the shoulder on a case. Back the die out and size the case. The ink on the shoulder should come out un marked. Progressively tighten the die in very small increments until the shoulder makes contact with the die. At this point if you eased into it slow enough, you will feel slight resistance closing the bolt on a chambered case. From here, 1/64 turn of the die advances the shoulder .0011607143". For practical purposes you can call it .001. Now you can back the die out .001 at a time, using fired cases with inked shoulders till the shoulder no longer contacts the die. Screw the die in 1/32 of a turn to advance it .002. If it chambers freely tighten the locking ring. This should do it, but if there is resistance closing the bolt, you have what is referred to as a crush fit. Advance the die 1/64 turn at a time until the bolt will close without resistance. Tighten the lock ring. Your die will now size your brass to your chamber.

The Hornady headspace comperator is much simpler and give you a measurement and is what I prefer.

Thank you gentlemen.

What resistance are you suppose to be feeling? I can fire a round eject the case pick it up and re-chamber it with no resistance above what a FL sized case has.

Depending on how aggressive your die is when it full length sizes the case body it will push the shoulder forward. You can measure it as it happens with a comperator. Your case to the shoulder may actually be a couple thousands longer than fire formed when the shoulder first makes contact with the die. There are some that like this "crush fit" and perceive it as advantageous for bullet alignment in the chamber.

Other than having to trim the neck, I'm just not sure that I understand how the case body/head to shoulder gets longer after full length sizing. At least that's how it reads to me.

When you run the case up in the die the diameter gets smaller. The only way for it to go is toward the neck. Before the shoulder is sized you can measure it there. When the shoulder is sized it is pushed on to the neck. The less you work the brass sizing, the longer it lasts.
Here is another way to describe what happens that may be clearer. When the cartridge is fired the brass stretches to the chamber dimensions. Ideally there is enough springback to allow extraction but this stretch has increased the surface area of the case. The case may actually be a bit shorter after firing due to this expansion. When it is ran into the sizing die the diameter of the body is forced into a smaller diameter once again but the surface area is not reduced. The result if the shoulder is not sized, is a slightly smaller diameter, slightly longer case body. When the shoulder is also sized, the neck, where you are used to seeing the excess, is the only place for the excess surface to go. Over time if the primer pockets and necks hold up and you continued to repeatedly work the brass and trim the excess the case would fail do to thinning. Some brands hold up to this much better over time and is one of the reasons Lapua is so desirable.

You guys really want to know the BEST way...? The F/L, collet die, hybrid method.

Find a piece of fired brass that is a tight fit in your chamber, or that you can't close the bolt on. Using a F/L sizing die with the neck sizing piece/decapper removed, start bumping the shoulder back .002" incrementally until you find where the brass chambers with slight resistance while closing the bolt. Now bump the shoulder back an additional .002" Now using the Hornady comparator as mentioned above measure from the mid point on the shoulder to the case head. Record this measurement and save it FOREVER. I actually scribe a line on the body of my die that lines up with an indicator on my press so that I know exactly where to seat that die back into the press in the future if I remove it for any reason. Now you know dimensionally that the brass will fit your chamber every time with those settings. *Some F/L dies will require that you open up the neck area so that they do not crush the neck closed to a point where the brass won't go into your Collet die without substantial force. I chuck my F/L die into a lathe and polish the neck area just enough to prevent this from happening. Sandpaper wrapped around a wooden dowel works perfectly for this.

Step 2. Insert Lee collet die into your press and run the brass up into it to size the neck. Pull brass out of die, spin the case 180 degrees, and run it back up into the collet die again. This method works. I have far fewer split necks using the Lee collet dies. I also anneal every 3rd-5th firing.

This works for me so I'm calling this MY BEST method.

Everyone I shoot with (F-Class) bumps the shoulder back .002. I saw some other folks wrote they only neck size and never have to FL or bump size but I've never had that much luck.

I'm in the same boat as you.. I've never found a rifle that will keep shooting the same pieces of brass without eventually needing to have the shoulder bumped back. They all get "sticky" in time. Some larger magnum calibers it happens in 2-3 firings. Other low power rounds might go as much as 10-15. Many variables factor into this but without fail ALL rifles will continue to grow, or stretch, the brass longer until it needs the shoulder set back. At least all of my rifles do this.

Evidently I missed this.

Cake and eat it too? Really? How is neck sized "better" than .002" shoulder bump? What is yeilded?

all else equal, the less you work the brass, the longer it lasts, no?

For my brass, primer pockets give it up before anything else. .002" shoulder bump for bolt actions, .005" shoulder bump for gas guns.

Tell yall what.

Those of you that insist on only neck sizing, keep doing it. I ask that you tell us all when you stick a case in the chamber.




Probably won't though.



And I probably will continue to see others' rifles that it happens to.

I get the feeling that there's a bit of confusion arising from assumptions in tjis thread.

You can partial FL size, and that is essentially bumping the shoulder.

You can neck size only.

You can neck size only and occasionally bump the shoulder by using a body die.

You can neck size MOSTLY, but periodically partial FL size to bump the shoulder, or even FL size occasionally.

You can FL size all the time and be done with it.

You can change your mind every time you load and do it any way you like.

It might be helpful if we are a bit more clear and thorough in our descriptions.

Does that mean all new brass gets stuck in your chamber on the first fire? That also means any factory ammo would jam too, no?

Correct, at least IME.

One thing that should be understood about partial FL sizing, aka bumping the shoulder with a FL die, is that the shoulder will actually flow forward to some extent before it gets pushed back. It might vary depending on the taper of the case and the size of the chamber, but it does happen.

I should add that a body die can do the same thing.

As I said, I haven't had a stuck, fired case via neck sizing only over the past 4-5 yrs, which is the time I started NS only. It still perplexes me how a fireformed, one rifle only case, can stick in the chamber of it's specific rifle after firing it. Given the fact you're not redlining your ammo of course.

So whereas with a fl die I am used to setting it for cam over and running down the entire brass.


To bump the neck I am just hitting the shoulder and not necessarily getting cam over

Is that fair?

Sounds right to me.

I don't know about sticking cases in the chamber, but I notice bolt closure getting tight after several firings when using neck sizing only. I'm loading about a dozen different cartridges though and may have failed to note that some are more prone than others. I probably should keep better records.

I agree with it getting slightly "tight". That's a good indication to me of a fully fireformed case conforming to my chamber. Less stretch, they last longer, at least in my feeble mind.

I had a few .308 Lapua brass out of a batch of 50 come out a little snug when closing the bolt which was annealed and full sized. What would you think the issue may be? Spring back because it was not perfectly annealed? I bumped back .002" as well. I was using 650 Tempilaq back then and started annealing for the first time and maybe it was not 100% cured, so I switched to 700 degree Tempilaq. I have not seen it do it much anymore, started annealing every firing now. What is your opinion?

My opinion? It may well have been as you think. Full annealing takes place very quickly at 750, and if it didn't reach that temperature, then maybe that's exactly what happened. I always anneal before any resizing, BTW.

Yes, I decap and anneal, tumble and resize.

It was once explained to me that no matter how truly concentric we believe the chambers of our guns to be, there may be slight variations. The chances of putting the brass in the chamber in the exact orientation it was fireformed in is unrealistic, and therefore might be a cause of a sticky chamber. Just something to consider...

When you guys mention that bolt drop starts to get a little tight on closure, that is your sign that your shoulders need to be pushed back. I can promise you-from personal experience-that the rounds that the bolt closes "tight" on WILL IN FACT shoot to a different point of impact than a properly sized cartridge that closes with no bolt resistance.

When they get that tight, it's time to bump the shoulder back at least .002", and then also trim to length, or at least measure the length as that case is telling you that the brass is flowing forward. You can test this theory. Find some brass that closes tightly in your chamber. Now reload it by neck sizing only. Now F/L resize and load 3 more rounds using the same bullet, powder, and charge weight. Now go and shoot those rounds. You will see that the "tight" brass will shoot on the paper away from the others. The farther out you can shoot, the more obvious this will be. It may be only a slight difference at 100 yards, but try shooting at 300 and the margin will be large enough to be easily evident. So, unless ALL of your brass has the exact same "crush-fit" in your chamber-which is not likely, then your accuracy will be affected by those rounds that have bolt closure resistance. This has been my experience. Yours may vary.