9mm Luger Brass Data

[DR Owl Creek]

This is data I have accumulated over a period of time, while trying to work-up the most accurate and consistent loads that I can. I thought I would share this with you.

Aguila (100 pcs): Average Weight 61.9 gr, ES 2.9 gr
Prvi Partizan (100 pcs): Average Weight 55.8 gr, ES 3.7 gr
Winchester (100 pcs): Average Weight 60.5 gr, ES 2.5 gr

Please add any other relevant data you have for 9mm brass, such as other brands, case neck thickness, case capacity, number of times reloaded, problems if any, etc. Loading comment and quirks with these cartridges would be appreciated too.

Thanks

Dave

[Old Caster]

All the 9mm get thicker not very far into the case. These cases can make a difference because the thickness can start sooner and something that can't be measured very accurately is whether the thickness starts sooner on one side than the other which might tip a bullet. 9 mm are kind of difficult to load with lead for a variety of reasons such as many different bore sizes over the years and bores so big that if a large enough bullet is put in a case large enough to ensure accuracy it will not chamber. People then run their loaded rounds through an FCD at which point they squash the bullet so small that the accuracy is lost.

I use Winchester because it is fairly common so I have more of them and the thickness around the mouth is one of the most consistent of them all but I would not discount any of the others because I haven't done what would be a comprehensive time consuming test that is hardly worth going through. If you can get good results with any of them go with it but if extreme accuracy is desired, especially with lead, I would stick with one brand in this caliber.

I did comprehensive tests with 45 ACP and shot many loads through a Ransom Rest with mixed brass and once fired Federal match brass and found no difference.

[DR Owl Creek]

Old Caster

Those were really good points about the case neck thickness varying from one side of the case to another. I read a study one time (& I don't remember where) that showed cases with thick necks on one side (or more) were thicker on that side all the way down to the web. Some people argued that this made a difference in case neck tension and bullet pull. Others argued it made no difference at all.

I don't have a lot of info on other brands of 9mm brass than Winchester because I was given several large buckets of brass from police qualifications years ago. I sorted it out by caliber and then by head stamp. I kept the Winchester because there was more of it, and gave the rest away. I probably have enough Winchester 9mm brass to last the rest of my life. LOL.

Dave

[Old Caster]

In the first quarter of an inch or so, the Winchester brass is pretty consistent as pistol brass goes but what I worry about is in farther where the brass quickly gets thicker like an internal hump. The longer the base of the bullet is, the more risk of a problem. I learned this initially with 32ACP brass where the bullet can only go in about .280 before it can upset the case. Trying to get accuracy in this caliber with lead has been a challenge.

[DR Owl Creek]

Good Point! I don't have a very reliable way of measuring case neck thickness at the various depths into the case like you mentioned. I think that enlargement could be a problem with some longer, heavier cast bullets too.

Dave