Neck sizing and bumping the shoulder

[Kwikvette]

This is what I consider to be the last of the series of threads since I dove into reloading months ago.

With the wealth of knowledge I've received here, I consistently load ammunition in .223, .308, and .300wm that yields 5 shot groups in the 3's. It helps that this is all done on a Forster Co-Ax single stage using RCBS Gold Medal Match dies.

This leads to the last part of reloading that I've yet to dive into; neck sizing.

To make things simple, we'll talk about 1 caliber for now.

I use Nosler brass that, when new, measures out to 2.2540-2.2560 on my Hornady headspace comparator. My fire-formed (once-fired) brass measures out to 2.2695 consistently.

I will be ordering a Neck Ball Vernier Micrometer but so far with my calipers, my brass measures out at .0115" thick (x2) and since I'll be using .308 my loaded round diameter is 0.331"

When choosing neck bushings, I'm reading/hearing that you should get 2 bushings in both .001" and .002" less than that of a loaded round's diameter.

Now the questions; Does the measurement of 2.2695 become the reference point for when I reload my brass several times? How do I figure out when exactly to bump the shoulder back? This is really the one I'm unsure about.

When neck sizing brass, how often is trimming required? I'll measure brass after every neck sizing, but I've read that there are times that some won't trim until after 3 firings.

Last but not least, when it comes to neck dies and bushings, who makes the best?

Feel free to throw out anything I may have missed.

[mulyhuntr]

Are you neck sizing only or are you using a full length bushing die and bumping the shoulder 2 thou?

I went with .002”-.003” under a loaded round with my bushings since I hunt with the ammo and want a little more neck tension. I know Redding recommends .001” under a loaded round.

[Kwikvette]

The only thing I haven't done is resize brass at all.

I've accumulated almost 1,000 pieces of .308 brass, and I've got around 400 pieces of .300wm brass. Sooner or later I will be processing this brass and shooting it out of the rifle the brass was formed from hence wanting to neck size.

I'm just not sure when the shoulder has to bumped back (if at all needed).

This is for precision only, no hunting.

[JagerDog]

The only thing I haven't done is resize brass at all.

I've accumulated almost 1,000 pieces of .308 brass, and I've got around 400 pieces of .300wm brass. Sooner or later I will be processing this brass and shooting it out of the rifle the brass was formed from hence wanting to neck size.

I'm just not sure when the shoulder has to bumped back (if at all needed).

This is for precision only, no hunting.

When it's stiff camming the bolt over.

[mulyhuntr]

If you only neck size you’ll eventually get to a point where the bolt will get hard to close.

I personally gave up on neck sizing only and now full length size with a bushing die, but only size enough to bump the shoulder .002” so as not to overwork the brass.

[MrElectric03]

I think lee makes the best neck die, the collet die. It squeezes the neck around a mandrel so the inside and neck tension is kept uniform. To use it on your co ax however you will need the plate to allow the use of a traditional shell holder.

That said I haven't played around with neck sizing much. I have been focusing all of my attention on load development with my .300wm for elk this year. For hunting I fl size. Want to try a Redding type S but haven't spent the money yet. Once I get a load set I may try the same load with neck sizing out of curiosity.

[OpenSightsOnly]

Boom!
+1

[bsumoba]

friends don't let friends neck size.

DO NOT DO IT!

FL Size your brass everytime. It will be more consistent, and it is a complete urban myth that it saves brass life. Whiden IMO, makes great sizing dies and I too, have a Co-Ax and it works great. My opinion is to use the expander ball in your sizing die, but you have to make that decision for yourself..

[Whiterabbit]

It’s so much easier to neck size on a progressive. I killed a FL die on a progressive, also brass rims, they tear more easily on a shellplate.

Dunno if hitting them with Hornaday one shot will help, but I suspect only if I hose them, I’d worry about my primers then.

[longrange1]

pretty much been answered by most...i like bsumobas answer.

neck sizing with bushing leads to doughnuts 99% of the time because the bushing dont go all the way to the neck shoulder junction and even if it did the bushing just continues to push brass into the area where it stops and with no expander ball...well you get it.

this is the cartridge i learned to hand load with and one of the first things i learned about was doughnuts.
if you insist on neck sizing get a redding body die and a lee collet die(LCD)run your brass through the body die as needed and size with the LCD but why do things twice when you can just FL size?

oh and to confuse you more...theres the larry willis collet die...pretty nice die but in my 4yrs and 4 barrel with the 300wm i never seen the need for it.

whidden dies are fantastic dies for the price..they are all i have used over the last 3 cartridges...if you want them more custom then what he has on the shelfs call him and send in some fried cases and he will make you a custom set for your gun...i use his off the shelfs myself..they produce tiny groups.

if you go with whidden get the expander ball set...worth every penny of the $60 bucks...a little tip...if you go with the whiddens and the ball set take the balls and chuck them up in a drill on the stem and polish them with some 2000 or 2500 wet/dry sand paper...makes them pull through the necks smooth as glass but make sure you measure them when done because they usually end up about .001 smaller after cleaning them up.

as far as the shoulder bumping goes i set my die to size the body and the shoulder stays the same as fired or .001 set back...ive found a snug case is more consistent...the BEST wat to set up your sizing die...size a case then chamber it...keep doing this and adjust your die until you get a slight resistance at the bottom of the bolt closing then size 5 and chamber them if the feel the same or close your set...every now and then youll get a tight one but not anything that you wont be able to chamber.

as far as neck tension i like .002-.003...if jamming bullets .001 which i dont do but have...to much or not enough neck tension will effect ESs and SDs ive found the above to be the sweet spot in everything ive loaded for.

[Meety Peety]

This is the practice I have adopted as well.

[NorCalFocus]

Delete this thread. Neck only sizing is more trouble than its worth.

[Kwikvette]

Mods, close this thread please!

I'll stick to FL sizing only; my buddy had given me his FL sizing die when I got the seating die from him.

[JagerDog]

Delete this thread. Neck only sizing is more trouble than its worth.

No trouble with collet die. Don't even have to lube.

[smoothy8500]

Mods, close this thread please!

I'll stick to FL sizing only; my buddy had given me his FL sizing die when I got the seating die from him.

I say leave it be, the off chance that in the future someone actually uses the search feature and may learn something...