Brass differences by brand

Has anyone noticed differences in shot groups from one brand of brass to another?

I didnt think there would be much of a difference as long as I didnt mix head stamps. But Ive been doing some ransom rest pistol testing the last couple weeks and my shot groups were a bit larger this past weekend then my previous test and the only difference was I used a different type of brass. 

If the type of brass does make a difference, what brands work better than others?

I have noticed significant difference in both thickness and consistency. For reloading 32 I have found it makes a real difference. I use Lapua for 32 long, Starline for 32 ACP. 

For loading 45, no noticeable affect (I use range brass) except for my 625 (which needs Starline).

Are you referring to a specific caliber?

I was using 9mm. In my first test I was using new starline brass. In my test this past weekend (I hadnt yet cleaned the starline to reuse) I used some once fired blazer brass which I have more than 2 buckets of. Shot group sizes @ 25 yards from the ransom rest opened up at least a half inch from the one week to the other. I was really surprised it was so significant a difference.

With my shooting ability there is no difference in accuracy.  I stay away from anything Aluminum, Steel, Berdan primed or heaven forbid 45 acp brass with a small pistol primer.  I do notice when I am reloading S&B and Fiochi brass seems to have slightly tighter primer pockets.

Yeah before ever testing from a ransom rest I wouldve blamed the difference on myself too. Ive actually learned a lot from using it already. I mentioned above that the groups grew by a half inch but thinking about it, it was more an average of 3/4 inch. Going from 10 rnd shot groups of 1.3" the first week to around 2" this past weekend. So it was pretty significant to grow that much

I have noticed some difference while using some sorted brass in 9mm too. Maybe because of the wall thickness or springing properties. ammo end up with different neck tension. They probably require crimp adjustment for best consistency. Many brands are so similar in dimensions, that there is no noticeable difference. Small test batch when switching brass head-stamp maybe helpful.

How many 10-shot groups did you shot with a given load?

I ask because if one were to shoot two 10-shot groups with the same load in the same brass, one might measure 1.3" and the other might measure 2.0".  One article showed a 2-fold, and up to an almost 3-fold difference in group size with 15-shot groups from a Ransom Rest with the same ammo. https://americanhandgunner.com/exclusive-consistent-velocity-accuracy/

S148 wrote:How many 10-shot groups did you shot with a given load?

I ask because if one were to shoot two 10-shot groups with the same load in the same brass, one might measure 1.3" and the other might measure 2.0".  One article showed a 2-fold, and up to an almost 3-fold difference in group size with 15-shot groups from a Ransom Rest with the same ammo. https://americanhandgunner.com/exclusive-consistent-velocity-accuracy/

+1. I am finding that getting really small consistent groups with the RR is quite elusive, with any caliber/bullets  .

I now shoot 30 round groups since there always seem to be outliers. With 30 shots I get a pretty decent idea of how they are grouping.

For lighter pressure rounds (38 Spl & 45) mixing brass doesn't have much of an effect at all.  The USAMU has done tests on that.  Brass headstamp and bullet seating depth are not critical for accuracy, but might be for reliable functioning.  

For the 9mm, which is a much higher pressure round, things get a bit more critical.  Separating by headstamp makes things more consistent by narrowing down the variances in case volume.  I found that bullet seating depth is also critical for accuracy in the 9mm.  It adds more work and testing, but you'll end up with a decent shooting load.

This is a very interesting thread, I will have to check lapua vs Starline brass for 9 millimeter. Also I agree about the ransom rest. 10 shot groups very quite a bit for me as well. I would say for example with my ransom rest I get one four inch group at 50 yards, two three inch groups at 50 yards and one good group at 2 inches. These are circular groups, and I've spent quite a bit of time trying to perfect my technique. It's pretty frustrating actually. I wonder if the right answer is to just do 30 shot groups and discount a couple outliers?

Here's an example of some 75-shot groups.  https://americanhandgunner.com/exclusive-crooked-seated-bullets-and-accuracy/

Putting all shots in one group has some merit for evaluating how well a gun likes the ammo.

Wmvdg123 wrote:This is a very interesting thread, I will have to check lapua vs Starline brass for 9 millimeter. Also I agree about the ransom rest. 10 shot groups very quite a bit for me as well. I would say for example with my ransom rest I get one four inch group at 50 yards, two three inch groups at 50 yards and one good group at 2 inches. These are circular groups, and I've spent quite a bit of time trying to perfect my technique. It's pretty frustrating actually. I wonder if the right answer is to just do 30 shot groups and discount  a couple outliers?

I suppose the question is whether the fliers/outliers are a result of imperfect Ransom Rest technique, or simply how the gun shoots the ammo.

Good point, yes I guess you can't count out any outliers. That's a great article.

There is a reason why many older shooters do 30 round test groups with the Ransom Rest.