Bullet Seating Question

[Achilles11B]

I’ve been reloading for a few years now, I know what I’m doing and how to do it safely but I’m far from an expert. Lately, I’ve been having issues with bullet seating. I’ve had no issues finding an accurate load for my rifle, the load process took a total of 50 rounds and there were no issues loading them. Now that I’ve found a good load, I’ve been having problems. The bullets are seated loosely in case. It happens frequently enough to where I’m holding back on loading more until I figure out what’s going on. Any help is appreciated. Thanks.

[P2000]

Sounds like poor neck tension. More details will be needed.
What dies/brass/process used? Is every cartridge loose like this?

[Achilles11B]

I’ve been getting the same results from Lee and RCBS dies. I use a mixed batch of brass, all once-fired from factory ammo, mostly Magtech and PMC. I decap, clean with a sonic cleaner, then measure, trim/deburr, prime, then add powder and bullet.

[P2000]

I’ve been getting the same results from Lee and RCBS dies. I use a mixed batch of brass, all once-fired from factory ammo, mostly Magtech and PMC. I decap, clean with a sonic cleaner, then measure, trim/deburr, prime, then add powder and bullet.

Assuming you are using Lee or RCBS full length resizing dies with the neck expanding ball, what is probably happening is your neck expanding ball is a little too large and is opening the neck diameter too much. You can test this theory by measuring the neck diameter of a piece of brass that has been run through the die, then remove the expanding ball, run a piece of brass through, and measure the neck diameter. You will notice the neck expanding ball is....expanding the neck. To reduce this effect you can chuck the expanding ball up in a drill and use sandpaper to reduce the diameter. Just go finer and finer with the grit to get a smooth finish at the end of the sanding process. And don't over do it.

That being said, most everyone here takes the expanding ball out of the full length resizing die and doesn't use it at all. Instead, a neck expanding mandrel die is used in a second step which expands the neck on the down stroke, resulting in more concentric and consistent brass. In my case, I use a Forster full length resizing die with expander removed, followed by a Lyman Neck Expander M Die. The M Die opens the neck up by 0.5-1.0 thou. When I seat a bullet the bullet opens the neck 1 thou, resulting in strong neck tension, I cannot force the bullet into the case by pressing the cartridge tip on my workbench one handed.

Unless you are really confident in the neck tension, go ahead and crimp for safety. Or crimp everything for crimp's sake.

[5.56 Bonded SP]

Sounds like you don't have your die adjusted properly.

Are you wanting to crimp or no? Screw your die down on an empty piece of brass with the handle in the fully closed position( so that the brass in the full upstroke) till you you feel resistance. If you don't want a crimp leave it there, if you want a crimp, lower the handle and then screw your die down 1/4 turn, set it there. Then adjust the bullet seating die.

[5.56 Bonded SP]

Even though the die might look a little different than whatever one you are using, just follow these instructions from this one minute video and you'll be set.

Hopefully this fixes your problem.

[P2000]

IMO crimping should not be used as a bandaid for poor neck tension. Crimping should be used in conjunction with good neck tension.
If the bullets are loose, that is a problem.

Also, is the OP even using a seat/crimp die? Is the OP crimping? So few details.

[Achilles11B]

Not looking to crimp. I appreciate the video and all of the other information, I’ll have to look at my dies again once I get home from work. Thank you all.

[bigedp51]

I’ve been getting the same results from Lee and RCBS dies. I use a mixed batch of brass, all once-fired from factory ammo, mostly Magtech and PMC. I decap, clean with a sonic cleaner, then measure, trim/deburr, prime, then add powder and bullet.

You are using mixed brass and the case neck thickness can vary and this can effect bullet grip.

Most dies have a expander approximately .001 smaller than bullet diameter and you may need to polish the expander down to .002 to .003 smaller than bullet diameter.

Below the Lyman type "M" expander is .003 smaller than bullet diameter,



NOTE, At the Whidden custom die website they sell expander kits with five expanders to help regulate bullet grip. The expanders run from bullet diameter to .004 under bullet diameter.

Bottom line, neck thickness, expander diameter and brass spring back control bullet grip.

[markm]

IMO crimping should not be used as a bandaid for poor neck tension. Crimping should be used in conjunction with good neck tension.
If the bullets are loose, that is a problem.

Totally agree. Ditching the expander ball and using a separate neck sizing die is optimal. But it adds another step.