Does anyone know...?

[moptop]

I once came across an article on the web on the subject on case length of 9mm reloads and the "trim, don't trim" rules of thumb. He when into great detail on the results of his finding dealing with accuratcy, operation, & pressures. I had this site bookmarked but when my computer crashed (of course!)I lost it along with info. I've searched my rear end off looking for it to no avail. [smilie=b:


Does this ring a bell with anyone and if so, could you pass along the address?


I would be forever greatful!

[runfiverun]

iirc handloader done an article like that about 10-11 months ago.

[HeavyMetal]

You'll also find an excellent article in Ken Waters "Pet Loads" his 9mm update is the diffinative work on the 9mm cartridge!

In it he cover both case length, as it affect accuracy, and case capacity as it affect pressure levels.

He covers almost all the commercial bullets available, at the time, and a butt load of powders as well.

He also has a good section on taper crimping.

All in all a great piece that should be on every 9mm reloaders bench BEFORE they size a single case in 9mm!

The rest of the is also worth looking at as well!

[moptop]

Here is the link to the article I was asking about. It gives some insite to the relationship between accuratecy and case lenght in the 9mm round. The are a lot of other very informative articles as well. Just thought I'd pass it along.


http://www.leverguns.com/articles/taylor/9mm_reloading.htm

[noylj]

At least in my testing, sorting by headstamp or case weight had NO affect on accuracy. He should have tested that and NOT assumed something.
In my tests of various auto pistol cartridges, case length was the determining factor. I found in 9x19 that cases of 0.750" and up gave the best accuracy, and the longest case I found was 0.752". If the referenced author had cases of 0.755", then he had cases that were 0.001" over max length and he needs to trim those cases (or sell them to a collector of rare cases). Out of thousands of sized cases, I have yet to find the mythological 0.754" case, much less the big brother 0.755".
I have thought about trimming 9x21 brass, but I shoot 9x21 and wouldn't want to confuse them. Also, I have an even bigger problem getting "long" cases for 9x21. Case drawings show 0.832" as max, but it is rare to find one as long os 0.825". Maybe I need 9x23 cases and I could trim them? Oh yeah, I have guns in 9x23...[smilie=b:

[243winxb]

A longer case removes end play, same as seating a lead bullet into the leade/rifling.

[fredj338]

It may be relavent in a match psitol, but in something like a Glock, isn't gonna matter much. I have fired 9mm in many diff guns w/ carefully prepared loads & stuff cobbled together w/ mixed brass, accuracy diff would be measured w/ caliper. FWIW, I have never trimmed a service pistol case, never.