Neck Sizing Vs. Full Length Sizing and Neck Tension

[Buck Fever]

Also, I'm cheap. Instead of getting a set of competition shell holders, I bought a set of steel shims for 1/2" bolts. I think they are used for leveling machinery. They are oversized a bit so they work with Magnum case heads, then I measure and carefully grind down a shell holder. After that I use the shim I need as a stop for the die and I'm not spending $$ on shell holders.

 

[Mike Matteson]

Lee's dies and no, I haven't.

Earlier I adjusted my FL resizing dies according to the instructions, which produces a brass that fits in any chamber. Now I've switched to resizing only slightly to bump the should slightly back, but I haven't fired the same cases often enough to actually see how much trimming is needed.

For hunting ammo I've always resized fully because I want the extra reliability it provides. For practice ammo I am tempted to only neck resize as it stresses the cases less and the brass prep procedure is faster and easier.

I understand where you are coming from. You can run some test without just shooting up the country side.
1. Set up and cut those cases to same length of whatever you like or do for the test.
2. you can just neck size some of your cases, and do a grouping test to check your size of group.
3. FL size and just bumping the shoulder back a couple of thousands and shoot for group.
Compare the groups, case growth, Note the times the case has be fired. I don't know if you anneal and how often either. Everybody is a little different or a lot different.
Now in days of old this is what I did.
Check my cases for length and trim if needed. I didn't hold to any length, just cut them back 10 thousands as needed, and move on. Didn't recut until max case length were out of spec. So all my brass was at different lengths. So not a standardize length. Only anneal once. I did case weight cases and set up close group to weight groups. I did trim my cases for neck thichness. Clean or debur my primer flash holes. I was careful in setting my primers to the same pressure
I worked on my powder loads, and felt I is was very accurate with powder weight. I measured, and scale all my powder loads. Bullets I didn't do much, just used them as they came out of the box.
I generally would run up the powder loads for more velocity. Most if not all my reloads ended up at about 1/2" @ 100yds. Still grouping under 3" @ 500yds. I held my shooting to that range. So depending on what you are going to do, or want is up to you. Below is where I am going to and have the equipment to do so. THE RABBIT HOLE. IT'S DEEP!
Now: I have upgraded all my reloading equipment over the pass last or a little more than a year. I have change out to bushing dies, and FL presently. The worst of it is my reloading gear is in Montana, and half the time I in Mexico-North. (aka Calif). I just have had a new wildcat chambering done, and just getting to load for it. Firs ever for a wildcat. Learning curve is and was interesting on get ready to set up and develop a round to use. Still acquiring componemts for the the rifle. I have the powder mostly, most of the primers, cases, and bullets. Primers are still hard to come by. Now I nornally use Fed 210 primers in the reloading. No mag primers, I don't feel that the Mag primers are needed, because my max loads at 75 grs in my larger belted mag. I do have some match grade primers, but I would like to a large selection. I am not stuck in the mud, so I will try and give every thing a try. If stumble over a great grouping combination out of the shut, then I will stay with that.
Generally I already know what bullet weight I going to use for that cartridge.
Now how I reload or going to.
1. trim my case all to the same length. 2. cut my necks for thichness. 3. clean my flash holes. 3. Set my primer pocket depth. 4. volume weight may cases to match. 5. seating primers to withing .001". 5. I am having a bullet sealing die to seat my bullet on the money. 6. I will fireform my cases. 7. I will anneal everytime. 8. I will resize my cases to FL but only bumping them a thousand or 2. 9. I will set up and run my case for length and trim as needed. 10. check my bullets for COA length of bullet. Just learn this trick last night, and thinking about checking for ogive too. I use a chronographs all the time at the range. I need to know that my loads are doing ES & SD.
Now You have me rethinking. So I will try and see what neck sizing does for me. It's just another die.

 

[Mike Matteson]

Sometimes I think that this sizing thing is about what works for you. Belted cases are, IMHO, an exception to the full sizing rule(?). I have similar sizing problems with my 300wm. I neck size all new and used cases now. Only full length them when it is a last resort. And get ready for the headache! Now with the non belted cases, I full length w/neck size all of them. All the time. It works for me and my cases typically last between 5-10 resizes.

Never had much problem with neck sizing with my belted mag. Sure deleted the case separations. I loaded hot. Generally 5 grs over book max too. You have to watch what powders you are using or more testing for temp change.

 

[C-130 Dude]

ok, well this makes more sense.
You are just doing a full length size with a bushing die that sizes the neck for neck tension.

Its just like the Forester dies that are bushing dies.

The full length die has the neck bushing part built in. Just select the correct bushing based on neck thickness, drop it in, and run the press handle like you normally do. Can't be much easier and puts out a pretty good product. Stay safe and have fun.

 

[C-130 Dude]

Also, I'm cheap. Instead of getting a set of competition shell holders, I bought a set of steel shims for 1/2" bolts. I think they are used for leveling machinery. They are oversized a bit so they work with Magnum case heads, then I measure and carefully grind down a shell holder. After that I use the shim I need as a stop for the die and I'm not spending $$ on shell holders.

Yup. That works well too. Whatever works, it's good!

 

[Veteran]

The full length die has the neck bushing part built in. Just select the correct bushing based on neck thickness, drop it in, and run the press handle like you normally do. Can't be much easier and puts out a pretty good product. Stay safe and have fun.

Yes, I use the forester bushing dies

 

[ARlife4me]

Ok, I don't want to start a food fight or anything, but I am curious what everyone on this forum has to say about this subject. I've seen the Erik Cortina video where he says neck sizing is just passe and so much old lore, and to just full length size for consistency. I've seen some other videos on youtube which sort of cite him and say they agree. However, in my own experience, I haven't so much run the tests to match up one method against another, its just that I learned the hard way you CANNOT full length size belted magnum cartridges past 2-3 times without head case failures. At least I could not. I had 6-7 head case failures on my .300 win mag. which of course is a belted magnum. I even had one lower half stay in the chamber so tight, I had to fill it with earplugs, then fill with an epoxy, and then ram it out from the barrell end.......not fun. So, now I neck size all my new Peterson Brass and have had no more issues or failures and I'm up to 5 times on that brass. Full length sizing at least with my RCBS dies just overworked the brass shoving it back down on the belt, and then the firing would stretch it back out until it failed above the belt in case head separation due to metal fatigue. No one ever told me not to Full length size belted cartridges, no book, no article, nobody told me. I had to learn the hard way.

But, I do full length size my .338 Lapua Magnum brass every 2-4 firings now, and neck size it the rest of the time, just to try to get a little more life out of it. I think just anecdotally I see better group sizes on it when I neck size it. I haven't run any real tests yet. Is there any real scientifically consistent and valid data run by anyone you can point me to who has done exhaustive testing on this subject as to group size vs. method?

Next, I've seen some videos by sdkweber and bolt action reloading on youtube where they ran some tests that seemed to indicate that either 2 thousands or 3 thousands neck tension is optimum for shooting small groups. Is there an accepted standard in the community and if so what is it, and can you again point me to any definitive studies that are scientific, exhaustive, and consistently run that says what the answer is?
One guy says 2 thousands works best, and another seemed to end up with a relationship what shows 1 thousands is worst, 2 thousands is better and 3 thousands is best in a curvelinear line that shows diminished gains at the 3 thousands mark, ie not much to be gained if any past that.
Does anyone have a magic wand or a crystal ball?

I'm just digging in and trying to get it right!

With my super-x brass from the late '70s and early '80s I've FL sized every time. The same brass more than 10 times and some over 15.

 

[C-130 Dude]

With my super-x brass from the late '70s and early '80s I've FL sized every time. The same brass more than 10 times and some over 15.

That's tough good brass. Wish I had a pile of it.

 

[436]

Lee's dies and no, I haven't.

Earlier I adjusted my FL resizing dies according to the instructions, which produces a brass that fits in any chamber. Now I've switched to resizing only slightly to bump the should slightly back, but I haven't fired the same cases often enough to actually see how much trimming is needed.

For hunting ammo I've always resized fully because I want the extra reliability it provides. For practice ammo I am tempted to only neck resize as it stresses the cases less and the brass prep procedure is faster and easier.

Got it, but... you might look into one, I've had very good luck with them for years... just saying. Cheers.

 

[Rosebud]

I understand where you are coming from. You can run some test without just shooting up the country side.
1. Set up and cut those cases to same length of whatever you like or do for the test.
2. you can just neck size some of your cases, and do a grouping test to check your size of group.
3. FL size and just bumping the shoulder back a couple of thousands and shoot for group.
Compare the groups, case growth, Note the times the case has be fired. I don't know if you anneal and how often either. Everybody is a little different or a lot different.
Now in days of old this is what I did.
Check my cases for length and trim if needed. I didn't hold to any length, just cut them back 10 thousands as needed, and move on. Didn't recut until max case length were out of spec. So all my brass was at different lengths. So not a standardize length. Only anneal once. I did case weight cases and set up close group to weight groups. I did trim my cases for neck thichness. Clean or debur my primer flash holes. I was careful in setting my primers to the same pressure
I worked on my powder loads, and felt I is was very accurate with powder weight. I measured, and scale all my powder loads. Bullets I didn't do much, just used them as they came out of the box.
I generally would run up the powder loads for more velocity. Most if not all my reloads ended up at about 1/2" @ 100yds. Still grouping under 3" @ 500yds. I held my shooting to that range. So depending on what you are going to do, or want is up to you. Below is where I am going to and have the equipment to do so. THE RABBIT HOLE. IT'S DEEP!
Now: I have upgraded all my reloading equipment over the pass last or a little more than a year. I have change out to bushing dies, and FL presently. The worst of it is my reloading gear is in Montana, and half the time I in Mexico-North. (aka Calif). I just have had a new wildcat chambering done, and just getting to load for it. Firs ever for a wildcat. Learning curve is and was interesting on get ready to set up and develop a round to use. Still acquiring componemts for the the rifle. I have the powder mostly, most of the primers, cases, and bullets. Primers are still hard to come by. Now I nornally use Fed 210 primers in the reloading. No mag primers, I don't feel that the Mag primers are needed, because my max loads at 75 grs in my larger belted mag. I do have some match grade primers, but I would like to a large selection. I am not stuck in the mud, so I will try and give every thing a try. If stumble over a great grouping combination out of the shut, then I will stay with that.
Generally I already know what bullet weight I going to use for that cartridge.
Now how I reload or going to.
1. trim my case all to the same length. 2. cut my necks for thichness. 3. clean my flash holes. 3. Set my primer pocket depth. 4. volume weight may cases to match. 5. seating primers to withing .001". 5. I am having a bullet sealing die to seat my bullet on the money. 6. I will fireform my cases. 7. I will anneal everytime. 8. I will resize my cases to FL but only bumping them a thousand or 2. 9. I will set up and run my case for length and trim as needed. 10. check my bullets for COA length of bullet. Just learn this trick last night, and thinking about checking for ogive too. I use a chronographs all the time at the range. I need to know that my loads are doing ES & SD.
Now You have me rethinking. So I will try and see what neck sizing does for me. It's just another die.

Haven't cleaned out a primer pocket in twenty years, makes no difference! Only look to make sure the flash hole is clear.

 

[C-130 Dude]

Haven't cleaned out a primer pocket in twenty years, makes no difference! Only look to make sure the flash hole is clear.

The only reason I clean out primer pockets is to make sure I can seat primers properly. And that's usually with the 34 and 41 types.

 

[C-130 Dude]

Got it, but... you might look into one, I've had very good luck with them for years... just saying. Cheers.

If you keep shooting those cases you will find out just how much those cases will stretch.

 

[Rosebud]

Before everyone here head explodes look up the science guy who test reloading equipment scopes,etc . He tested primers by height and seating depth. From, from .121 height to .131 and media group of .126 shot them all , after long winded explanation it made no difference! He crushed them, set them just touching the back of the pocket and just off touching the back of the pocket. No differences!

 

[Veteran]

The only reason I clean out primer pockets is to make sure I can seat primers properly. And that's usually with the 34 and 41 types.

Yep, if you let those primer pockets get too dirty, it can take gorilla force to seat them or you can crush and ruin them when they get cattywampus. So, I think every so often at least better brush them or scrape them out w brush or reamer.

I do it everytime just to make it easy to seat them.