Full Length or Neck Only; What's Best Resizing for Accuracy?

[J E Custom]

None of the USA Palma Team's rifles with custom 308 Winchester short chambers having less than SAAMI spec freebore had such data marked on their barrels.

I hear you. And that is to bad, but it does happen But I stated that the chamber differences "SHOULD" be placed on the barrel to prevent someone from loading the wrong ammo If there are changes that differ from SAMMI. I see it all the time and sometime have to make repairs because someone used the wrong ammo and many time it is the smiths fault because he did not mark the correction on the barrel.

I recently repaired a rifle with a stuck bolt because the owner did not know It had a tight neck and no freebore. He bought it and was not told what the difference in the chamber was over the standard chamber and he just bought factory ammo and the rest was a bad day.

Over the years I have seen many chambers miss marked that caused problems.
The reamer markings should identify any deviation from SAMMI, and the smith should permanently mark that on the barrel ID for safety even though it may not be a problem when firing SAMMI ammo.

One such chamber is the 223 Wilde. it will handle both the 556 and the 223 with ease. But the Barrel ID needs to reflect the difference in my opinion.

Thanks. maybe your post will encourage others to know for sure what chamber they actually have and not assume.

J E CUSTOM

 

[Orange Dust]

Full length sizing returns the brass to a factory state if the brass you are reloading was SHOT IN THE WEAPON YOU ARE RELOADING IT FOR THEN AND ONLY THEN DO YOU NECK SIZE! As to your question being the round was fired in your weapon yes neck sizing will align the bullet better but only because the brass is fire formed to your weapons chamber.

Not really true. F/l dies do not resize to factory unless they are sb dies. Properly set up fl dies size ammo to only fit that specific chamber. Neck dies especially bushing ones can induce runout in the cartridge due to lack of support for the body.

 

[BigJohnH]

Not really true. F/l dies do not resize to factory unless they are sb dies. Properly set up fl dies size ammo to only fit that specific chamber. Neck dies especially bushing ones can induce runout in the cartridge due to lack of support for the body.

You may want to read more about setting up dies to return the brass to factory specifications.

 

[Mram10us]

Again don't ask if you already know the answer.

You ask If you were missing something and all I did was try to help You.
It sounded like you didn't understand the different purposes of the two Specifications. It sounds more like you just want to argue.

I will leave you with it and, let you make the same mistakes that I did over the years.

Have fun

J E CUSTOM

You have a habit of spelling out what others say in a lot more words

 

[okie man]

You have a habit of spelling out what others say in a lot more words

thats good for slower folks like me!

 

[Bart B]

I recently repaired a rifle with a stuck bolt because the owner did not know It had a tight neck and no freebore. He bought it and was not told what the difference in the chamber was over the standard chamber and he just bought factory ammo and the rest was a bad day.

Several SAAMI spec chambers have no freebore. 30-06 and 300 Win Mag are popular examples

 

[Edd]

Several SAAMI spec chambers have no freebore. 30-06 and 300 Win Mag are popular examples

The chambers you speak of don't have a parallel free bored section like is traditionally thought of as "freebore" but because of their throat dimensions they provide a space in front of the bullet equivalent to what a parallel freebore would provide.

A 30-06 has a space the length of a .3085" diameter freebore that is .1641" long.

 

[257RobertsMan]

Below Kevin Thomas who worked in the Sierra Ballistic Test Lab and now shoots for Team Lapua USA.
Click on image to enlarge

This!!! At one point in my reloading I keep meticulous records on FL vs Neck Sizing only with the same rifles and loads. I also keep records comparing crimping vs not crimping on these same loads. It's been my experience that I gained very little and in most cases accuracy suffered (slightly) from neck sizing only, same with crimping as a finial step.

 

[Methow Packer]

THIS... AND to back up what he said, if you don't skim turn and square up the necks to true them, I don't feel either method has any effect on accuracy whatsoever as long as they are sized properly. In fact, there is a faction that believes if you don't prep your brass you are actually better off using small base dies and completely sizing cases back to nearly new factory dimensions. They feel this allows the case to self align in the chamber somewhat, like a factory round. For our purposes (a long range precision rifle) I feel very strongly every round of brass should be fully prepped and sorted. Great loads cannot be either consistent, or duplicated without this step. Leave this step out and you will always be chasing your tail for accuracy. You can find a load that shoots the magic 1/4" group. Go home and load up a bunch and the next group just may be 1-1/4". Doesn't take long to turn, trim and chamfur the necks, ream the flash holes and primer pockets on 100 cases. Doesn't take long to sort them by weight either. I don't sort them until they have been fully prepped.

Does this apply to all brass. Norma, Nosler, ADG ? Do these cases require the same attention?

 

[richhymas]

I've been doing the same lately. I also quit neck turning as it never really improved accuracy. My runout has improved significantly just by removing the expander ball and using a mandrel for neck tension.

I have also converted to sizing my neck with a bushing only where possible No expander ball for my bench guns. If I had to expand I would do it with a mandrel pushing down from above rather than pulling from inside, but my first choice is to not run anything on the inside of the neck where possible.

 

[Orange Dust]

Does this apply to all brass. Norma, Nosler, ADG ? Do these cases require the same attention?

Yes

 

[Orange Dust]

You may want to read more about setting up dies to return the brass to factory specifications.

Why in the world would you want to? And no you cant without small base dies.

 

[Bart B]

A 30-06 has a space the length of a .3085" diameter freebore that is .1641" long.

Not in the current SAAMI chamber shown on page 95 in their rifle cartridge and chamber document referenced in my earlier post #85. No freebore between chamber mouth and throat.

The 1 degree 22 minute angled throat (leade) starts at the .3106" diameter chamber mouth tapering to .3000" bore diameter.

 

[J E Custom]

Several SAAMI spec chambers have no freebore. 30-06 and 300 Win Mag are popular examples

Most cartridges that have no freebore have a big lead angle to do about the same thing. And Many of the older cartridges were designed this way because they limited COAL by the magazine length so they were loaded to allow for this.

The good thing about it is that if you do a SAMMI chamber, it will/should be just like the SAMMI specifications and factory ammo will work for the same reason. one of the reasons that we sometimes have to throat a chamber is the newer heaver bullets we like to shoot.

Another reason I like to identify any changes to a SAMMI chamber, is to be able to use different bullet shapes and COAL.

If you added freebore to the 30/06 for heavy bullets, you should identify the change because it would no longer Be a SAMMI chamber.

Maybe I'm just worried that someone buys a rifle that doesn't have enough information to buy or load the correct ammo for it.

J E CUSTOM