Different types of brass

Reloading equipment, methods, load data, powder and projectile information.

Different types of brass

Post by JimTom » 15 Feb 2018, 3:12 pm

G’day All

Another question for the Yodas’ of reloading.
I have two different types of .308 brass, ADI and Lapua. I have heard that the adi brass is a little thicker in the wall therefore giving you ever so slightly less volume in the case than the Lapua, which will I guess will lead to a difference in pressure and a different point of impact. If this is true would it be a significant difference? Just thought I’d ask before I try it out next week.
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by No1Mk3 » 15 Feb 2018, 5:11 pm

G'day Scooter,
Significant is relative. To the hunter or casual target shooter the variation you will see is not much, but to the fullbore shooter working at or near maximums the difference could be disastrous. In general we tend to load start loading mil spec brass from 5 to 10% lower than commercial brass due to the pressure variations, and do not mix the rounds due to impact variations which in a major comp at long range could cost you a Super-V and lose the match. (I never have to worry about that, if I even GET a Super I'm happy!) Cheers.
No1Mk3
Second Lieutenant
Second Lieutenant
 
Posts: 2090
Victoria

Re: Different types of brass

Post by sungazer » 15 Feb 2018, 5:22 pm

Even to the competition shooter in 308 class the difference is nearly negligible. Of course you would only shoot the one head stamp in any Range. Most competitors if they have the opportunity will weight batch sort the brass as well. Most will not be loading to max capacity either. The longer barrel gets the velocity up there where it is needed well short of a maximum load.
sungazer
Sergeant Major
Sergeant Major
 
Posts: 1525
Other

Re: Different types of brass

Post by JimTom » 15 Feb 2018, 5:42 pm

I will only be using it for hunting, so shouldn’t be too many issues then. Thanks again gents.
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by duncan61 » 15 Feb 2018, 6:12 pm

I had a heap of assorted .243 brass and I ended up sorting it and only keeping the Winchester as It seems to be a good case and I annealed it all and have had no issues at all.
.22 winchester .22hornet .222 .243 7mm rem mag cbc 12g
User avatar
duncan61
Officer Cadet
Officer Cadet
 
Posts: 1905
Western Australia

Re: Different types of brass

Post by Gwion » 15 Feb 2018, 6:30 pm

I would personally sort them into different brands (head stamps) and use the different brands for different loads/bullets/veloicities.
User avatar
Gwion
Colonel
Colonel
 
Posts: 3978
-

Re: Different types of brass

Post by JimTom » 15 Feb 2018, 7:08 pm

I see your point mate, regarding using for different loads etc.
I am going away on a bit of a trip and the brass I ordered more than likely won’t be available before then, which in turn forces me to load up two different types to ensure I have sufficient ammo for the trip.
More interested in whether or not I will have to re zero when I change from one type of brass to another or will the change be buggar all.
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by sungazer » 15 Feb 2018, 7:33 pm

The velocity will be the biggest variable that would cause POI changes so if you have a chrono or access to one run the two bullets over it and change one a necessary to get the same velocity
sungazer
Sergeant Major
Sergeant Major
 
Posts: 1525
Other

Re: Different types of brass

Post by JimTom » 15 Feb 2018, 7:41 pm

Mate I am no where near technical enough to own or use a chronograph. ;-)
I guess I will just go and shoot both types at the range and see what the actual change is.
Thanks everyone for the input.
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by Oldbloke » 15 Feb 2018, 8:37 pm

Gwion wrote:I would personally sort them into different brands (head stamps) and use the different brands for different loads/bullets/veloicities.


Mmmm, that's sort of what I do. Use the same load but load in batches depending on brass brand. e. g. I don't mix them.
The greatest invention in the history of man is beer.
https://youtu.be/2v3QrUvYj-Y
Member. SFFP, Shooters Union.
SSAA, the powerful gun lobby. :lol: :lol: :lol: :lol:
Hunt safe.
User avatar
Oldbloke
Field Marshal
Field Marshal
 
Posts: 11192
Victoria

Re: Different types of brass

Post by JimTom » 15 Feb 2018, 8:42 pm

Yeah I wasn’t going to mix them up. Would be loaded as two different batches.
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by Gwion » 15 Feb 2018, 9:00 pm

Only way to know is to load up some of each at the same load, shoot groups with each and see how far out your POI is. It might be close enough to not matter or it might. At least you can see why the impact changes and record you required changes on your turret so you don't need to do it in the field.
Weighing the cases will also give you an idea how much different they are. Not each case, just a few of each HdStp.
User avatar
Gwion
Colonel
Colonel
 
Posts: 3978
-

Re: Different types of brass

Post by wanneroo » 16 Feb 2018, 1:36 am

It's possible that ADI brass is actually 7.62x51 NATO brass. There are some slight differences in internal case dimensions which result in a slightly lower case capacity. One thing to do is to take both pieces of brass and fill them to capacity with either water or powder and see what that weighs in as. If there is a difference then you'll know for sure.

I mix brands and 7.62 NATO and 308 Win brass for my standard plinking load to be shot at 100 metres. But that load is nowhere near max. If I was loading for accuracy and distance with closer to max loads I definitely would not be doing that.
wanneroo
Warrant Officer C1
Warrant Officer C1
 
Posts: 1412
United States of America

Re: Different types of brass

Post by JimTom » 19 Feb 2018, 11:32 am

Well for those who are interested I took .308 to the range and shot two different types of brass out of it at a range of 100m using the same load and projectile. They seemed to both shoot the same as per the attached target. Disregard the two marked shots as they were not part of the test. The circled group contains six shots, three with ADI, and three with Lapua. In this case the two different types made very little difference.
FF119824-9CD1-4C39-A1CF-A529FE959C7B.jpeg
FF119824-9CD1-4C39-A1CF-A529FE959C7B.jpeg (488.12 KiB) Viewed 4597 times
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by Gwion » 19 Feb 2018, 12:13 pm

Well, there you go. Certainly do you for the hunt!

My reasoning would be that if you are on a good node at the lower/mid range of charge then I would expect that kind of result. If you were getting up to higher charges, you may see more variation due to pressure differences. Then again; it's all speculation and depends what you call good results. I'd say they look pretty good.
What size is that red square?
User avatar
Gwion
Colonel
Colonel
 
Posts: 3978
-

Re: Different types of brass

Post by JimTom » 19 Feb 2018, 12:20 pm

G’day Gwion

Mate the target is marked in inch squares. The extreme spread of the group is just on an inch. I am happy with an inch at 100m bearing in mind that it is just a hunting rifle and I’m definitely no target shooter :-)
I agree totally with what you say regarding the variance in pressure if you were loading compressed or close to max loads. I never load to max so in this case the difference is negligible. Well I can’t shoot well enough to descern any significant difference anyhow.
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by Gamerancher » 19 Feb 2018, 3:21 pm

Load 'em up and go huntin' Scooter. Have fun!
User avatar
Gamerancher
Sergeant Major
Sergeant Major
 
Posts: 1596
New South Wales

Re: Different types of brass

Post by JimTom » 19 Feb 2018, 3:26 pm

Thanks mate. Will definitely be doing that in the not to distant future.
User avatar
JimTom
Second Lieutenant
Second Lieutenant
 
Posts: 2130
Queensland

Re: Different types of brass

Post by Gwion » 19 Feb 2018, 4:10 pm

:thumbsup:
User avatar
Gwion
Colonel
Colonel
 
Posts: 3978
-

Re: Different types of brass

Post by Oldbloke » 19 Feb 2018, 7:25 pm

Gamerancher wrote:Load 'em up and go huntin' Scooter. Have fun!



Yep
The greatest invention in the history of man is beer.
https://youtu.be/2v3QrUvYj-Y
Member. SFFP, Shooters Union.
SSAA, the powerful gun lobby. :lol: :lol: :lol: :lol:
Hunt safe.
User avatar
Oldbloke
Field Marshal
Field Marshal
 
Posts: 11192
Victoria


Back to top
 
Return to Reloading ammunition