NORMA BRASS

[rifleman700]

Yesterday afternoon I went to prep some new Norma brass that I have for my 7saum and as I pulled the box out I remembered that when I bought the brass that I could not get all that I wanted in one lot so I had to buy from two different lots to get the 250 pieces total that I felt I needed for the life of the rifle. I normally will only buy brass in individual lots, but at this time brass was to hard to find so I purchased one lot of 150 packaged in 25 round bags and found another bulk box of 100 from a different vendor.

When I started my bbl break in and load development I pulled from the packaged / bagged brass first and used this brass - 80 pieces for both of these tasks. The only thing I did to prep this brass was to I/O chamfer the case mouth. After bbl break in I measured some fired cases for case capacity coming up with 71.1 grs h20 on average.

When I saw the box of 100 that had not been opened I wondered how much difference in weight there would be between these lots. And yes, the lot numbers were different. So I measured all of the remaining new brass and put them into the following groups regardless of lot.

14- 229-229.9 grs
53- 230-230.9 grs
69- 231-231.9 grs
29- 232-232.9 grs
4- 233-233.45 grs

Lightest- 229.05 - 305.95 w/h20 - 234.55 w/primer - 71.4 grs case capacity
Heaviest- 233.45 - 309.80 w/h20 - 238.90 w/primer - 70.9 grs case capacity

Even though I have these grouped in 1 grain increments the 231 and 232 groups actually fell into a half grain spread within each group.

Next I will pressure / velocity test the low and the high to see what slight difference there may be in the half grain window from lightest to heaviest.

I thought this might be some good info for those who may have questions about the quality of Norma and Nosler brass. In Nosler brass I have used 7rum, 7stw and 28 Nosler and although I have never weighed them I have measured case capacity with multiple samples of each and found them also to be excellent.

My first choice is always Lapua but I have had no issues with Norma and Nosler brass. My son uses 300WM brass head stamped Barnes ( Norma ) with equally good results.

 

[4xforfun]

So, are you volume testing new brass that has never been fired and comparing them to fired brass? I guess I am not following.

I am slow!

Tod

 

[hoz53]

Yesterday afternoon I went to prep some new Norma brass that I have for my 7saum and as I pulled the box out I remembered that when I bought the brass that I could not get all that I wanted in one lot so I had to buy from two different lots to get the 250 pieces total that I felt I needed for the life of the rifle. I normally will only buy brass in individual lots, but at this time brass was to hard to find so I purchased one lot of 150 packaged in 25 round bags and found another bulk box of 100 from a different vendor.

When I started my bbl break in and load development I pulled from the packaged / bagged brass first and used this brass - 80 pieces for both of these tasks. The only thing I did to prep this brass was to I/O chamfer the case mouth. After bbl break in I measured some fired cases for case capacity coming up with 71.1 grs h20 on average.

When I saw the box of 100 that had not been opened I wondered how much difference in weight there would be between these lots. And yes, the lot numbers were different. So I measured all of the remaining new brass and put them into the following groups regardless of lot.

14- 229-229.9 grs
53- 230-230.9 grs
69- 231-231.9 grs
29- 232-232.9 grs
4- 233-233.45 grs

Lightest- 229.05 - 305.95 w/h20 - 234.55 w/primer - 71.4 grs case capacity
Heaviest- 233.45 - 309.80 w/h20 - 238.90 w/primer - 70.9 grs case capacity

Even though I have these grouped in 1 grain increments the 231 and 232 groups actually fell into a half grain spread within each group.

Next I will pressure / velocity test the low and the high to see what slight difference there may be in the half grain window from lightest to heaviest.

I thought this might be some good info for those who may have questions about the quality of Norma and Nosler brass. In Nosler brass I have used 7rum, 7stw and 28 Nosler and although I have never weighed them I have measured case capacity with multiple samples of each and found them also to be excellent.

My first choice is always Lapua but I have had no issues with Norma and Nosler brass. My son uses 300WM brass head stamped Barnes ( Norma ) with equally good results.

I like 7mm guys- anyway now you have the lots mixed up?

 

[rifleman700]

So, are you volume testing new brass that has never been fired and comparing them to fired brass? I guess I am not following.

I am slow!

Tod

No, just showing the consistency between two different lots.

 

[rifleman700]

I like 7mm guys- anyway now you have the lots mixed up?

I will test the low and high weighted brass first and then will shoot the rest of the new brass in the field for practice. I will then weigh all of the brass again after a more thorough case prep but I don't expect any surprises.

Current 7mm's

7-08
7-08 Ackley
7saum
7rm
28 nosler

 

[284winner]

Norma brass has been good, consistent and reliable brass for me. It's pricey and so I will always choose Lapua all things being equal but if I find a good deal on it, I'll always choose Norma over WW, Rem, Fed etc.

 

[butchlambert]

Is it for a BR rifle?

 

[Shynloco]

Are you surprised by your findings AND do you sort new bullets "marked" as in the same lot out? That you may find will give you similar results, whether they be Bergers, Sierras and any other brand. Neither of those findings are anything thats news.

Alex

 

[rifleman700]

Is it for a BR rifle?

Hunting rifle. I set up all of my rifles for long range or to the cartridges effective range and therefore use the best components I can.

 

[rifleman700]

Are you surprised by your findings AND do you sort new bullets "marked" as in the same lot out? That you may find will give you similar results, whether they be Bergers, Sierras and any other brand. Neither of those findings are anything thats news.

Alex

I was expecting there to be a difference between lots and there was not so this did surprise me.

I used to sort bullets but don't anymore. I now establish a BTO measurement with a dummy round and zero my comparator at this setting. (This dummy round will stay with my dies and will only change if I need to chase the lands and need to establish a new BTO setting.) I then seat every bullet after this around .010" long and then check it with comparator to see how much more I need to seat it to get to the exact same BTO as the established dummy round. The OAL measurement will vary from round to round but the BTO measurement will all be the same.

I also like to buy my bullets in bulk lots. I try to pick a bullet that I will use for the life of the rifle and then buy enough to last for the life of the rifle.

 

[Shynloco]

I was expecting there to be a difference between lots and there was not so this did surprise me.

I used to sort bullets but don't anymore. I now establish a BTO measurement with a dummy round and zero my comparator at this setting. (This dummy round will stay with my dies and will only change if I need to chase the lands and need to establish a new BTO setting.) I then seat every bullet after this around .010" long and then check it with comparator to see how much more I need to seat it to get to the exact same BTO as the established dummy round. The OAL measurement will vary from round to round but the BTO measurement will all be the same.

I also like to buy my bullets in bulk lots. I try to pick a bullet that I will use for the life of the rifle and then buy enough to last for the life of the rifle.

I agree with your assessment and "generally" buy bullets having the same lot numbers, even if not in bulk size (500 items). But there is no evidence that all the bulk came off the same machine. In other words, say Berger or Sierra is running machines #1, #2, #3 making the same bullets. In my experiences, I've not seen anything that guarantees the bullets made off those three machines, aren't mixed together before being packaged. Now I know about the "lot" theory, yet I have friends who compete and sorts their bullets. I've watched them sorting bullets made by the aforementioned manufacturers and opening new boxes of 100 or 500 bullets and then came up with four groups of one, and then as many as seven groups of the other. That after all bullets were trim "pointed." And the boxes were marked with the same lot number. So yes it is a good idea to try and group bullets as close to each other as humanly possible to achieve best accuracy. But in the real world of limiting variables, its tough to do and additional steps are necessary to limit differences from box to box or even within a box itself. And none of that is to say that those aren't quality bullets. Because they are as I continue to believe Berger, Sierra and Lapua bullets are at the top of the list of bullet manufacturers.

Alex

 

[rifleman700]

I agree with your assessment and "generally" buy bullets having the same lot numbers, even if not in bulk size (500 items). But there is no evidence that all the bulk came off the same machine. In other words, say Berger or Sierra is running machines #1, #2, #3 making the same bullets. In my experiences, I've not seen anything that guarantees the bullets made off those three machines, aren't mixed together before being packaged. Now I know about the "lot" theory, yet I have friends who compete and sorts their bullets. I've watched them sorting bullets made by the aforementioned manufacturers and opening new boxes of 100 or 500 bullets and then came up with four groups of one, and then as many as seven groups of the other. That after all bullets were trim "pointed." And the boxes were marked with the same lot number. So yes it is a good idea to try and group bullets as close to each other as humanly possible to achieve best accuracy. But in the real world of limiting variables, its tough to do and additional steps are necessary to limit differences from box to box or even within a box itself. And none of that is to say that those aren't quality bullets. Because they are as I continue to believe Berger, Sierra and Lapua bullets are at the top of the list of bullet manufacturers.

Alex

I have heard that before and it makes sense and may be the reason for some lots that have a lot of variance. I find Lapua bullets to be the most consistent although I don't use a whole lot of them.

 

[7Saum]

I was expecting there to be a difference between lots and there was not so this did surprise me.

I used to sort bullets but don't anymore. I now establish a BTO measurement with a dummy round and zero my comparator at this setting. (This dummy round will stay with my dies and will only change if I need to chase the lands and need to establish a new BTO setting.) I then seat every bullet after this around .010" long and then check it with comparator to see how much more I need to seat it to get to the exact same BTO as the established dummy round. The OAL measurement will vary from round to round but the BTO measurement will all be the same.

I also like to buy my bullets in bulk lots. I try to pick a bullet that I will use for the life of the rifle and then buy enough to last for the life of the rifle.

Hi,
I also use Norma Brass in my 7saum, I found the same thing,very consistent,off topic but have u tried any loads with RL 26,if so how was it for ur rifle...
Thanx

 

[rifleman700]

Hi,
I also use Norma Brass in my 7saum, I found the same thing,very consistent,off topic but have u tried any loads with RL 26,if so how was it for ur rifle...
Thanx

Yes I have tried RL 26. It is a very linear powder and worked very well. Velocities and accuracy were outstanding. The thing I don't like about it is the burn properties of this powder cause 95% of the burn to happen around 8" down the barrel and this it makes it very hard on the throat and will reduce barrel life. I have since gone back to H4831. FWIW QL shows that N560 and Magpro to also be good powders.

 

[SheepDog]

Yes I have tried RL 26. It is a very linear powder and worked very well. Velocities and accuracy were outstanding. The thing I don't like about it is the burn properties of this powder cause 95% of the burn to happen around 8" down the barrel and this it makes it very hard on the throat and will reduce barrel life. I have since gone back to H4831. FWIW QL shows that N560 and Magpro to also be good powders.

How do you know that 95% of the powder burns at 8" down the barrel?
All the tests I have seen on rifle and pistol powders is the they all burn in the first few inches. I am curious on what evidence you have to support this.

 

[butchlambert]

How do you know that 95% of the powder burns at 8" down the barrel?
All the tests I have seen on rifle and pistol powders is the they all burn in the first few inches. I am curious on what evidence you have to support this.

Do you have that reference at your finger tips? I bet it would be interesting a good read.

 

[rifleman700]

How do you know that 95% of the powder burns at 8" down the barrel?
All the tests I have seen on rifle and pistol powders is the they all burn in the first few inches. I am curious on what evidence you have to support this.

Green line shows where the powder reaches the 95% - 8.3". The pink line shows where the complete burn takes place - 15.6". The PMAX and Z1 are on the same line which shows this load to be a good load when you factor in velocity, pressure and barrel time - OBT.

As you can see by the graph, peak pressure occurs in the first few inches and I think this is what you are referring to when you are talking about the first few inches.

 

[fguffey]

I have Norma brass, I do not use it because reloaders covet it. I had rather purchases pull down cases and once fired and then form my cases. I can only guess that is why my rifles belch flames out of the barrel and if I was guessing I would say most of the flames exit out after the bullet. So I can only guess the night sky lights up because I am not using Norma brass

And then there is that 2 to 3 inch thing with the two lines. I am not the fan of the spike but when I want my powder burning seriously and efficiently I need to jam the bullet into the lands because I want my line to go 'almost' vertical. I have seen vertical lines that indicated 80,000 pounds. To me that is scary, to avoid that vertical spike I back my bullets off to give them that running start because I want my bullets the have that jump. I do not care if the flame goes out 6" into the bore or 1 foot beyond the muzzle, I do care about case travel, I want to reduce case travel. Back to the flame going out, I believe it is a bad habit to allow the flame to go out too early, if there was a big advantage to a short powder burn there would be no advantage to having a long barrel.

F. Guffey

 

[dkhunt14]

I have Norma brass, I do not use it because reloaders covet it. I had rather purchases pull down cases and once fired and then form my cases. I can only guess that is why my rifles belch flames out of the barrel and if I was guessing I would say most of the flames exit out after the bullet. So I can only guess the night sky lights up because I am not using Norma brass

And then there is that 2 to 3 inch thing with the two lines. I am not the fan of the spike but when I want my powder burning seriously and efficiently I need to jam the bullet into the lands because I want my line to go 'almost' vertical. I have seen vertical lines that indicated 80,000 pounds. To me that is scary, to avoid that vertical spike I back my bullets off to give them that running start because I want my bullets the have that jump. I do not care if the flame goes out 6" into the bore or 1 foot beyond the muzzle, I do care about case travel, I want to reduce case travel. Back to the flame going out, I believe it is a bad habit to allow the flame to go out too early, if there was a big advantage to a short powder burn there would be no advantage to having a long barrel.

F. Guffey

Maybe you need to post pics of these little groups and teach us all how to do it.

Then there is the fact that Norma brass wins a lot of shoots. Then there is the fact that short cases or powder colums have been winning and setting many records in shooting. Whether it is the PPC in short range, the 6 BR or IMP versions in 600 or 1000 yards, or the 300 WSM in 1000 yards. They all have one thing in common, shorter powder columns and accuracy. Matt

 

[fguffey]

They all have one thing in common, shorter powder columns and accuracy. Matt

And before that I said the length and diameter of the powder column made a difference. That was back when some case heads had a thickness of .250" and others had a case head thickness of .200". I know, you are confused but the case head with the thinness case head of .200" was the heaviest case meaning the case head with a thickness .250" weighed less. I could ask what difference would that make but no one had a clue then then. Most were too involved in the H2O water thing.

F. Guffey