Case capacity - formed 280 AI lapua 30/06 vs Nosler 280 AI brass

[AckleymanII]

I know the 30/06 will have a shorter neck, I have a lot of once fired lapua 30/06 brass. Has anyone checked the volume difference between these two cases? I don't have any Nosler brass on hand to compare the capacities to. All loading data I see is with the Nosler brass.

I fire formed 100 of the once fired 30/06 Lapua brass and never lost a case in the process with 15g of bullseye and Cream of wheat. Cases were 95%+ formed with just a slight roundness of the shoulder, very minor.

thanks in advance

 

[msinc]

I would like to know this too...it would be especially good to know which one has the higher capacity. I am shooting either fire formed 280 Remington brass, which works fine, or Hornady. With either of these it would be nice if they were larger than they actually are when using Reloder 26. With heavier bullets, 168 grain and up, I am still getting no signs of any pressure at all with compressed loads and the velocity is still going up.

 

[Alex Wheeler]

Cant help you but I am curious what the loaded neck measures after you neck down the lapua case. As a side note I find the 280ai wont show pressure until its too late. Be careful.

 

[AckleymanII]

Alex, I turned the necks, eliminated a butt load of potential problems. X caliber barrel is shooting groups in the high 2's and low 3's, 168g Berger hunting with h4831SC, fed 210's, at 56-57g, another node at 59-60g, bullet touching the lands. 60 is considered a safe working max load for the rifle.

The 30/06 Lapua brass is tough as pig iorn as you would expect, but it is work. First forming was with 15g of bullseye and cream of wheat, with 1/8" rounded shoulders, then fire formed shooting 57g of H4831 SC and 168g Bergers. Great accuracy.

Most people would never go to the trouble for Lapua '06 brass, but I love it. I Got the brass free as it was once fired.

The X caliber barrel has never had anything but a tinge of copper in it, an cleans up very easily.

 

[AckleymanII]

Most issues with Necking down can be eliminated by neck turning at the parent case dia, in this case, 30 caliber. Part of what you neck down is fire formed into the Shoulder. If you want extreme uniformity and eliminate doughnuts for many, many firings, this is how to do it. Necks to be absolutely perfect, will be neck turned again at 7mm.

Lapua brass is tough in 30/06, worth the effort if you like to tinker. If you want to stand on the throttle with 180's, this is a no brainer.

 

[gunsandgunsmithing]

When you neck a case up, the thicker brass in the shoulder becomes the bottom of the neck.
When you neck down, just the opposite...the bottom of the original case neck becomes the top of the shoulder.

 

[AckleymanII]

Correct. When you neck turn on the larger 30 cal dia, neck down, now fire form. Part of the original neck is now part of the shoulder(what you said), and it is thinner in that small area, thus doughnuts take longer to form. Since you neck turned prior to fire forming, the part of the neck that goes into the shoulder is thinner than the other shoulder material. I never had any necks come off with this method.

Do a clean up neck turn for uniformity at 7mm after you have necked down, if you desire.

Most would prefer to just do one neck turn, thus they would choose to neck turn at 7mm, this is problematic.

Neck turning at 30 caliber first, then 7mm gives benchrest quality neck run out, and eliminates a flock of problems in doughnuts forming for a number of firings.

I formed perhaps 10,000 -22 and 6 ppc cases from PMC 7.62x39 cases for working over dog towns...the brass is very tough if you can find any. I shot zero freebore chambers. It took a while for doughnuts to form using the method above.

Back when I was shooting benchrest, we necked up to 25 caliber, neck turned, then neck down to 6mm, did a clean up cut, then fire formed twice, did another clean up cut.

 

[msinc]

Thanks for posting Ackleyman, good info to know. I have an X-caliber barrel on one of my 223's. It scoped out flawless inside and looks as good or better than barrels costing way more. It is undoubtedly one of the most accurate rifles I currently have, but it seems soft. It machined very easy and the thread cut beautiful, but in not very many rounds I scoped it just to have a look and noticed burning at the throat. It is not bad and the rifle still shoots as good as it ever did, but it has started to burn. I just got a Muller barrel for another project. It too is flawless looking, but it seems even softer than the X-Caliber.

 

[CTK]

Cant help you but I am curious what the loaded neck measures after you neck down the lapua case. As a side note I find the 280ai wont show pressure until its too late. Be careful.

Is this based on using the 30-06 Lapua brass? I never had this problem with Nosler Brass with the 280ai. I have owned 3 and they all seemed to show pressure signs at or slightly below book max for the given load. I guess that I could have been already at high pressure but don’t think so based on common book loads and 3 rifles. 2 were Sammi chambers and one was the 280 rem Ackley improved. My 6.5x47 is what scares me.