I Shot Some of the New Norma 6PPC Yesterday

jackie schmidt

jackie schmidt

New member
I put a new barrel on my Rail Gun, and since I had bought 100 of the new Norma Cases, I thought I would try them in my .269 neck chamber. With the Barts .790 Boat Tail, that is about .0035 clearance on the loaded round. Pretty loose, but not maybe too loose. I picked out 15 cases that had no more than .0005 wall variation in the neck thickness.

The main thing I wanted to see was how the brass stood up to the same 3400+ fps plus loads.

First, the brass, while having a thicker solid part of the base, actually has a tad more capacity. You can plainly see it in how far the charge comes up in the neck as opposed to a Lapua Case.

This new barrel is a tad suspect. I worked it up with Lapua, and never really found the sweet spot. It cleaned up good, seems to have no issues, it just doesn't shoot that well. A couple of times it spit shots that would destroy an entire agg, so I feel like it is destined for join other bretheren in the "stand in the corner" crowd.

When I shot the Norma, I had no issued with extraction at all. The primer pockets stayed tight over the 4-5 firings on each case, and I actually nailed a 10 shot group in the mid "ones". It did not back it up, the next produced two popped shots that made a big "two", I am blaming the barrel, as it showed no promise with the Lapua.

The one thing of concern was growth. Using the exact same sizing and 'bump' as I use on the Lapua, the cases grew .010 after just 3 firings. I did not even notice this untill I felt a funny crunch as I closed the bolt on one. They all started out in the 1.505-1.508 range, and all had gone past 1.515 after just three firings. I double checked how much I was bumping the shoulder, and it was just at .001, same as always. The new Lapua Cases I stared out with had about the same nunmber of firings, and showed hardly any growth at all.

I was using a .264 bushing, the loaded rounds measure about .2655.

I wish I would have brought one of my older but proven barrels. I doubt this tomato stake was worthy of any kind of testing. But, the brass will take the pounding, or so it seems, aside from the growth issue.

I really need to get a .266 neck chamber so they could be turned, but getting a reamer right now is like winning the lottery.........jackie
 
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jackie schmidt said:
The one thing of concern was growth. Using the exact same sizing and 'bump' as I use on the Lapua, the cases grew .010 after just 3 firings.
Click to expand...

Thank you for this..

Your findings match mine very well, however as stated yesterday there seems to be a limit around 30 gr of N133 where the stretch starts. Being on right side of the limit they stretch normally, but they do not seem to be liked to be pushed too far. With my 09-N133 30 gr and a 65 gr BT bullets seems to be close to what they can take before the stretch appears.
 
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Keep testing Jackie, I like reading what you write. I however have not found the case growth situation myself. I dont normaly shoot hot loads but very moderate for sure. 28.8gr N133 29.7gr 8208PD around in that area. I wonder what would make the cases grow? Any thoughts? I also wonder if it will come to a halt after 3 or 4 firings? I know this brass comes pretty short on the head space well at least mine did. I think my cases blew out about .007 on the first firing. I wish that wasnt the cases but it is what it is. I am going to continue using this norma brass, as i think it makes a lot of since. For me anyway! Lee
 
Skeet, you are right on the headspace. While my chambers are not really "standard", they are pretty close to what every body else uses.. My cases are just like yours, a full .008 shorter on the headspace. I simply fired them in my fireforming rig, and went from there..........jackie
 
I hate to ask this....but besides the .010 length growth have you noticed any varience in the neck thickness? have any of the cases with the .010 length increase
shown any increase in neck thickness?
 
Mark
I just measured some of my cases that have been fired 8 to 10 times and my necks are still the same. This is just my experience though. Lee
 
skeetlee said:
I also wonder if it will come to a halt after 3 or 4 firings?
Click to expand...

My experience is that it will not given that you shoot the hot loads. I have done up to 10 fireings with this brass using more than 30 gr of N133 and the growth never stopped. Also, by then it was surprisingly easy to seat a primer which is something I do not like.

At the amounts of powder you mention the growth is close to what I would call normal. I cannot say where the magic limit is, however it does seem to be around 30 gr of N133 also depending on the bullet you are using.
 
Uniform primer pockets?

Jackie, did you adjust the depth of the primer pockets? Or did you measure them.

I find that these are not as deep as the .220R brass and more uneven as well. Any thoughts or experience?
 
I know your not asking me but here is what i have found. The Norma pockets measure on average .122 deep. My current lot of lapua .1235 deep. this is an average over 20 pieces of each. Extream spread on the norma was .121 to .123 fairly consistant to be honest. The lapua was a little more consistant at .123 to .1235 and a couple that were .124. Lapua wins here for sure. However i uniform my pockets with a fixed sinclair tool and it cuts .124 deep maybe .1243 if we want to get that picky. With the uniform tool i have and use i have had several lapua cases were i couldnt clean them up uniformaly because some of the pocket was already deeper than my cutter. With the norma i dont have this issue as my cutter cleans them all up 100%. Does any of this matter. I would guess not much. At least i cant tell if it does. Please know this. I user and like Lapoua brass very very much. I have a bunch of it and i will continue to use and buy it in the future. I personaly just like this new Norma brass a little better. Does it shoot any better? No probably not. It just seems to work for me and i dont have to shoot this stuff two times before i got to the line with it. You do have to shoot it at least one time as the headspace is short, but even then i have shot some real nice groups. I most certainly would use it unfored in a club or local match. I wouldnt do that with a 220 russian that hasnt been fired. I havent experienced the trim issues you fellas have, but even then i am a trim addict anyway. I like for my brass to be as consistant as possable, so i just do it. Would i recommend Norma over Lapua, Probably not. I am not the calibure of shooter one would want to take to much advise from anyway. I am just a simple folk who happens to really have a love for fine rifles and small groups and good people. Thats all i know about it! Lee
 
Does anyone have any new or additional info to add to what has been posted here?
 
If case necks are lengthening then the cases are slipping in the die.

"Growth" isn't a hardness issue, it's a headspace and sizing issue.

If the cases are growing, if the necks are lengthening, then you will get donuts at the n/s junction.

Also, when necks are growing, the brass has to come from somewhere. This 'somewhere' is the body of the case just above the web, the expansion ring that shows on the case when you resize. All that extra brass being trimmed off the top is being robbed from the bottom.

al
 
I really need to get a .266 neck chamber so they could be turned, but getting a reamer right now is like winning the lottery.........jackie[/QUOTE]

Jackie, since this barrel is suspect and their probably isn't anything to lose, set it back and chamber with an old .262 reamer and turn the brass accordingly. At least it will prove if turning the necks improve anything with Norma brass, and save having to buy a reamer before you know it will work. One of those rainy day projects!:)
 
I always thought that cases grew more after annealing and shooting hot loads than without annealing, but I may be wrong.
 
Jackie,
I use a Harrel Vari-Base die. It only sizes the base of the case, bumps the shoulder and the neck (with the usual bushing). As long as I am careful about bump, case growth seems to be minimal (Lapua brass) . If you don't know anyone with one of these, perhaps a bump die could be used on a case that has been fire formed, but which has not gotten too tight at the head, to help pin down which part of the sizing is responsible for your cases' growth. I was able to select a base bushing that only reduces the diameter above the extractor groove by about a half thou' and the diameter of the shoulder is untouched. What does your die do in these areas?
Boyd
 
Liseo said:
I always thought that cases grew more after annealing and shooting hot loads than without annealing, but I may be wrong.
Click to expand...

Good reason not to anneal :)

BTW, I agree with you, this is why I don't anneal. Once you start sliding brass around those corners the cases will grow. They have to. You slip the brass and it has to go somewhere......

al
 
Food for thought

For those of you who may not know, the 300 yd Sporter world record (.247!) was set in 2004 at Raton by Bob Dodd using Norma brass.
I was at the bench to his left and watched the group form late in the match. With one shot left and 30 seconds left the wind reversed and Bob was forced to hold 2 rings or so. The last shot did not open the group at all!
ba
 
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