Does brass matter?

Marbles

WKR
Classified Approved
Joined
May 16, 2020
Messages
4,499
Location
AK
So, does brass and headstamp matter?

If it does, then why:
-Internal volume?
-Brass alloy?
-Neck tension?
-Consistency?

I have 4 headstamps in 223 available to me.
1. Starline, purchased as new brass, loaded and shot twice before.
2. Sig that came to me as loaded ammo (purchased a few months ago), reloaded once before.
3. Federal (FC) that came to me as loaded XM556FBIT3M (purchased about 10 years ago, first shot in the last few weeks), never reloaded.
4. Winchester nickel plated brass that came loaded (purchased about 10 years ago, first shot in the past few weeks), never reloaded.

I loaded 100 rounds in random order, then selected 10 of each headstamp at random to test accuracy. All were full length sized, after sizing, if close to 1.76 in length they got trimmed using a Lyman E-ZEE trimmer. In randomly selecting I did not check if I got trimmed or untrimmed cases.

Rifle is a Tikka T3x Lite cut to 16.5 inches.

Load is 23 gr of N135 with a 77 gr TMK with Federal 205 primers. VV load data has a reputation for being on the light side, and I checked for pressure in Starline brass going up to 24 grains before loading mixed brass at VVs max load for that powder with a 77 gr TMK.

I'm shooting prone over a pack and using a wad of game bags as my rear bag.


Any predictions on accuracy, ES, and SD between the different head stamps?



If you want to tell me I'm stupid, well thanks for confirming that I'm at least right about something (that I'm stupid). 😃

In the order fired

Starline
star10.jpg

FC
FC10.jpg

Winchester
Win10.jpg

Sig
Sig10.jpg

My first question was, is there a fluke, I expected the starline to perform the best (I had selected the 150 starline brass I'm using in total for similar case weights out of the 500). Unfortunately, I did not have enough starline or FC loaded the same to retest. But I was able to shoot the following groups.
Win16.jpg
Sig16.jpg
Star5.jpg
FC4.jpg

My next question was how would the groups over lay, i.e. was the group center and zero the same for each brass type. Using the distance from aim point the Hornady app provides, I created an excel graph. The first is the 10 shot groups.
Orange = starline
Blue = Win
Yellow = Sig
Gray = FC
Scatter.png

Then I decided to add in the other groups (16, 16, 5, 4). The starline almost sets the group size on its own.
Scatter 72.png
 
Last edited:
OP
Marbles

Marbles

WKR
Classified Approved
Joined
May 16, 2020
Messages
4,499
Location
AK
Here is a table with the chronograph data and group data. I have had pretty large SDs and ESs, and now I'm pretty sure it is due to the starline brass. I am predominately using Forms reloading approach, so I'm not chasing perfection, but as I want to shoot long range an SD less than 20 would be nice.
Table.png
(the "Scrubbed starline 9" column is what the starline group would look like without the single high and right shot).

Now, the question is: why is the starline the poor performer on ES and SD? My assumption was that it had to do with case capacity. The Winchester and Starline both had markedly higher velocities than the Sig and FC. Consequently, I predicted the Winchester and Starline cases would have a lower H2O capacity, resulting in increased pressure.

As my resizing die also decaps and expands, I did not want to full length resize, then put spent primers back in. Given that all cases were fired from the same chamber under similar pressures measuring fire formed capacity should be consistent for the sake of comparison.

I numbered the cases, 1-10 for each headstamp. I left the water and cases on the reloading bench during the day to minimize the water changing temperature and the corresponding change in density. All weights were obtained using a draft cover. I weighed the case, recorded the weight, then filled it half full of water, then vigorously tapped the base against the bench while holding the case at an angle to eliminate bubbles, I then filled it until the meniscus protruded from the top, I would then remove the excess water with a knife so I consistently had water flat at the mouth. Then weighed again. When I decamped the cases all primers were soaked, so I think I did a good job avoiding air trapping. Just incase not having trimmed the cases effected capacity, I measured all case lengths. Eyeballing it, I do not see a correlation and do not think this effects the assessment of case capacity.

The full table is not displaying every time, so I broke it up.
sig tab.pngwin tab.pngstar tab.pngFC tab.png

All cases are numbered, decided to reload them, this time with 22 gr N135. I will shoot in order and compare chronograph data to case capacity. This time I trimmed all brass just to keep neck length consistent. I'll shoot them tomorrow and update. I need to refresh on how to work with correlation in Excel.

Groups from round two with the same brass, this time I loaded 22 gr of N135, rather than 23 gr like last time.
FC.jpgwin.jpgstar.jpgSig.jpg

Interestingly, the Starline had the best SD this time.
 
Last edited:
Joined
Sep 11, 2017
Messages
1,428
Location
Bozeman, MT
It makes a difference, although whether or not it “matters” depends on the end use case. Too bad you couldn’t add a very high end headstamp into the mix such as Lapua, Lapua or Lapua. Or maybe Alpha.


Sent from my iPhone using Tapatalk
 

Tom-D

FNG
Joined
Sep 11, 2023
Messages
80
in my experience i havnt seen it matter unless your chasing bench rest accuracy. I don’t often shoot a long way though.
Im heaps keen to see what your results are but!
 
OP
Marbles

Marbles

WKR
Classified Approved
Joined
May 16, 2020
Messages
4,499
Location
AK
Updated.

It makes a difference, although whether or not it “matters” depends on the end use case. Too bad you couldn’t add a very high end headstamp into the mix such as Lapua, Lapua or Lapua. Or maybe Alpha.


Sent from my iPhone using Tapatalk
I would like to have some Lapua mixed in, but I don't have any. I know Lapua has a great reputation, part of which is based on durability. What exactly would be expected to change in a single round of loading? Better accuracy? Better ES and SD? If measured, more consistent case volumes?
 
Joined
Sep 11, 2017
Messages
1,428
Location
Bozeman, MT
Updated.


I would like to have some Lapua mixed in, but I don't have any. I know Lapua has a great reputation, part of which is based on durability. What exactly would be expected to change in a single round of loading? Better accuracy? Better ES and SD? If measured, more consistent case volumes?

Better ES/SD. I would think with careful measurement you’d see the consistency, but I’ve never bothered. I let my testing/results inform my opinion. I chase a very high standard for my ES. Sub 20 for sure, and I like to be closer to 10 across a 10 shot string. I’ve gotten to where I won’t even consider a cartridge if there isn’t Lapua brass. It’s just the easy button, if your process is consistent, with good bullets, I’ve never had an issue. With other brass brands, it’s been all over the map.

I realize that level of consistency doesn’t really “matter” for most hunting that most people do. But if you’re into any sort of longish range shooting, it’s a very important variable to take out of the equation


Sent from my iPhone using Tapatalk
 
Joined
Apr 2, 2013
Messages
551
Location
Idaho
I haven't spent the time to officially record my data but my journey into reloading has shown me that yes brass matters. If you care for it to matter.

I have spent the most time reloading for .223 rem so that is what I am basing my opinion off of. I have chased small ES/SD I have hand sorted cases by weight and by internal volume, shrank every variable I could. I then bought 2 boxes of Lapua cases and watched my SD/ES rapidly shrink it was now half as much as my best assortment of hand sorted cases.

Accuracy at 100 yards stayed the same. Accuracy at 600 yards improved a lot with that consistency increase.

I just started tinkering with Starline brass in the same rifle. Since .223 Lapua brass is nonexistent. And so far im not impressed. Ill probably go back to LC brass and dealing with the primers since its free.
 
Joined
Jul 30, 2015
Messages
6,321
Location
Lenexa, KS
I do think it matters, and I think you have demonstrated that quite well.

My experience with Lapua, there is less case capacity than something like a Hornady, so you can't fit in as much powder. Or, perhaps for the same amount of powder, you get higher pressures. It is heavier, that's for sure. It's the most beautiful brass there is, IMO, and I love the look of a finished round representing the future death of a furry little varmint. Makes my heart warm, ya know?
 
Joined
Feb 16, 2024
Messages
21
Great topic. I’ve performed water volume tests on different brass and found differences in same caliber. Obviously volume affects pressure which effects velocity which effects POI. The only caliber I’ve really paid any small attention to differences in 6.5CM. I’ve shot Win, Hornady and Lapua brass and ran group comparisons at 100 yds when zeroing but saw no comparable differences that couldn’t simply be ruled as just me the shooter.
Although the smallest differences at 100 mean huge differences at 1000.
What I feel the main brass difference is, is longevity. I shoot exclusively Lapua for that reason based on research. I’ve yet to cross the 5x reload mark since I switched exclusively to one brass brand. Time will tell now that I’m keeping a good log.
 

jhm2023

WKR
Joined
Jan 2, 2018
Messages
650
Location
AK
The main reason I use nicer brass like ADG or Peterson is because it lasts longer since I almost always load at or near max. Not having to sort brass or discard a certain percentage due to wild inconsistencies and having lower ES are bonus reasons for me. Other than that, I think good and consistent case prep is the key to happiness. I do like Starline for my bulk ammo for gas guns though.
 

pods8 (Rugged Stitching)

WKR
Rokslide Sponsor
Joined
Mar 12, 2014
Messages
4,608
Location
Thornton, CO
I speculate (but am not an expert) that case volumes and powder combos and if you are near max pressure will probably factor into how much it affects things. Some brass volumes differ notably in some cartridges.
 
Joined
Feb 2, 2020
Messages
2,737
Volume makes a difference in velocity. 284win brass: win highest vol, then Lapua, then Peterson.

In my cartridge there's about 1.5gr water weight difference in capacity between Lapua and Peterson
 
Joined
Dec 30, 2014
Messages
9,732
My sample of one T3x lite barrel seemed to shoot a little better below top pressures. Not sure if the higher pressure of the smaller starline cases could have anything to do with it.
 
Top