I have a couple of thousand pieces of mixed headstamp 9mm brass in my reloading inventory. Some of it started as virgin brass, some of it is from factory ammo I personally shot and a bunch of it is range pick-up. I inspect each case for splits or other trouble before I load it. Any piece that gives me pause just gets tossed in the recycle bucket. 9mm is too plentiful to fret over IMO. However, I have quite a bit of Blazer, Speer and FC mixed in that will not give proper neck tension. I have done as much research on the subject as I can and it seems to be an issue for many but not all. I'm pretty far down the road with this and have already done a lot of trouble shooting like: resetting the sizing die making sure it is set all the way down making contact with shell holder, tried belling case mouth less and not at all, measuring expander plug, measuring bullets etc. The problem is isolated to Blazer, Speer and FC brands (of the headstamps I have) hereafter refered to problem brands. If I use Win or RP brass I get a nice coke bottle shape and no set back. I can feel the difference through the press when sizing and seating the bullet. With the problems brands there is almost no resistance when seating the bullet. After seating the bullet, it can easily be pushed into the case 0.015 or more by pressing into the bench. This happens with both X-Treme 124gn plated hp and Precision Delta fmj. There is no change in length measurement of the bullet itself. Many have described these brands of brass as "thin walled" which makes sense and I believe would explain the problem. I have read about the Lee and the EGW undersized die which undersizes by between .001 and .003 depending on which one you get. EGW website says .001 and Lee says .002 to .003. Lee makes them for EGW, but suposedly they are different. The product description for the Lee die says: "Undersized dies work great for bringing back case tension to hold bullets on cases that may be thinner walled."
My question is 1) anybody have this same problem and try the undersize die to solve it? 2) If so, how did it work? 3) Any reason to go with the EGW version over the one directly from Lee or vise versa? 4). Can/should the undersize die be used on all my brass, even those that aren't giving me issues or do I need to keep them separate? Any other advice that I may not have tried is also welcome.
My question is 1) anybody have this same problem and try the undersize die to solve it? 2) If so, how did it work? 3) Any reason to go with the EGW version over the one directly from Lee or vise versa? 4). Can/should the undersize die be used on all my brass, even those that aren't giving me issues or do I need to keep them separate? Any other advice that I may not have tried is also welcome.