Not too long ago I experienced one failure to ignite with one round of WWB 9mm. This has only happened to me once with this ammo, and I figured it was just a faulty primer.
Well, I pulled the bullet from the case of this round, and just out of curiosity I took my calipers out to measure the bullet diameter. It measures just under .354" (.3535").
Just for the heck of it, I measured the widest exposed diameters of 124gr Golden Sabers, Gold Dots, and the cheaper Federal Champion 115gr from Wally World...they all measure just under .354".
Is this a standard for factory produced ammo in this caliber? I could see that these slightly under-sized bullets might feed more reliably, with less potential to bulge the mouth of the cartridge case, but assuming the groove diameters of most barrels are at least .355", wouldn't these smaller-diameter bullets adversely affect accuracy?
When I reload, I always measure the diameters of a few of the bullets before assembling the cartridges, and if it says ".355" on the package of jacketed or plated bullets, and ".356" on the cast lead...well, that's what they usually measure up to.
I never seem to be able to group the
premium factory rounds as well as my reloads (loaded to near maximum charges in my reloading data), and up to now, I didn't really give it much thought, except to assume that the +P factory loads fly faster (and with slightly more recoil than my reloads), and so my ability to shoot these rounds accurately might be diminished.
Have any of you noticed this smaller factory bullet diameter thing, and if so, do you have any ideas about whether or not accuracy might suffer because of it?
Bullet Diameters of Factory-Loaded 9mm Cartridges
Linear Mode
