kilotanker22
New member
So, for a long time, I have seen the slight bulge left near the base of a bullet when I load 9mm Luger ammunition. They have never failed to fire or chamber so I never gave it a great deal of thought. Well, I sat down to load some defensive ammo the other night with new cases and Hornady XTP bullets, when I saw that the bulge was more pronounced than they are normally. I am using a Lee pro 4000 press, and the powder through expanding die that comes with the kit. I experimented with expansion to see if that works, but that die does not expand into the case, it only creates a belled case mouth.
I figured that the new cases might be a little undersized so I tried to run a few through the press after removing the sizer die. To my surprise, I found no bulge, or evidence of a bulge at all. The only variable that changed at this point was the removal of the sizer die. The rest of the ammunition loaded up and looks perfect. They seem to cycle better as well in both guns I fired them in this weekend. They have always cycled fine, but they feel like they chamber more smoothly.
So, it would appear that my sizer die is responsible for the diameter of the case being a bit tight and causing the bullet to have to expand the case as it is seated. For new cases, this is no problem, however I have not decided how to remedy this when I am recycling cases. Reloaded brass does not have as much bulge as the new brass, but it is still present. I am pretty sure that the reloaded brass is a little harder and not as easily sized as new cases are, that's why they display less bulge than new cases.
My question is, will I damage the carbide insert in the sizer die if I were to maybe polish the inside of it to remove some material? Damaging the surface of the carbide is a real concern of mine. Does anyone have a suggestion for a die that won't size cases so darn small? My next step is to play with the die to see if I can back it off, sizing the case a little less and remedy this issue. Like I said earlier, they still run in my pistols, but this has been bothering me for a while now. If they can do it at the factory in mass production, we, as reloaders, should be able to replicate that.
I figured that the new cases might be a little undersized so I tried to run a few through the press after removing the sizer die. To my surprise, I found no bulge, or evidence of a bulge at all. The only variable that changed at this point was the removal of the sizer die. The rest of the ammunition loaded up and looks perfect. They seem to cycle better as well in both guns I fired them in this weekend. They have always cycled fine, but they feel like they chamber more smoothly.
So, it would appear that my sizer die is responsible for the diameter of the case being a bit tight and causing the bullet to have to expand the case as it is seated. For new cases, this is no problem, however I have not decided how to remedy this when I am recycling cases. Reloaded brass does not have as much bulge as the new brass, but it is still present. I am pretty sure that the reloaded brass is a little harder and not as easily sized as new cases are, that's why they display less bulge than new cases.
My question is, will I damage the carbide insert in the sizer die if I were to maybe polish the inside of it to remove some material? Damaging the surface of the carbide is a real concern of mine. Does anyone have a suggestion for a die that won't size cases so darn small? My next step is to play with the die to see if I can back it off, sizing the case a little less and remedy this issue. Like I said earlier, they still run in my pistols, but this has been bothering me for a while now. If they can do it at the factory in mass production, we, as reloaders, should be able to replicate that.