Loads out of round

[tding]

I noticed that a small percentage of a recent load of 9mm Luger boolets were "out of round" by as much as .003" and would not "chamber" in a Dillon headspace gauge. However, the rounds do chamber in my Baretta 92FS and I will attempt to shoot them, although I suspect that accuracy will be affected.

I'm guessing that the cause may have been that either I did not "bell" the cartridge sufficiently, or that I was careless when pressing the boolet into the cartridge, or some combination of both.

None of my manuals seem to address this issue. Can anyone offer any insight?

 

[Walkalong]

I'm guessing that the cause may have been that either I did not "bell" the cartridge sufficiently, or that I was careless when pressing the boolet into the cartridge, or some combination of both.

I agree, but there is the slight possibility your sizer die is out of round.

 

[rcmodel]

9mm Luger boolets were "out of round"

Are you saying your bullets are out of round?
Or, your loaded rounds are out of round?

Bullets are not round:
1. Cast lead bullets (tumble lubed) that have not been run through a luber/sizer die are out of round due to mold cavity being out of round.
2. Mold blocks are being held open slightly by lead stuck to the flats.

Loaded ammo is out of round:
1. Cast bullets are not round. (see above)
2. Insufficient case mouth bell.
3. Bullet seating stem does not match the bullet shape you are using.
4. Excess crimp is deforming the case.
5. Sizing or crimping die is not round.

rc

 

[loadedround]

rcmodel: You omitted one possible problem, the lock ring on the seating/crimp die not tightened down causing the die to "wobble" when seating a bullet.

 

[rcmodel]

Yea! That too. I didn't think of a loose die.

Another one I didn't think of is, the shell holder doesn't fit the cases you are using.

Lee for one makes two different shell holders (#19 & #6) for the 9mm Luger, and if you pick the wrong one for the brand of brass you have, it may not align the case in the seating die perfectly every time.

rc

 

[Walkalong]

.003 out of round is poor for cast bullets unless sloppily made. (Mold not close completely) It sounded like he meant loaded rounds. It could be a combination of things. .001 out of round boolit, poor belling and seating, a loose die, etc

 

[tding]

Thanks for the insight

After reviewing everyone's comments I'm willing to bet that the seating stem in my die did not align with the bullets correctly. I was seating Speer 3997 bullets (jacketed soft point) using an RCBS die with a round nose seating stem. It looks like I may have had better results with the semi-wad cutter stem.