9mm bulge? from a Dillion 650

VCMC168

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Hey Everyone:

I'm starting to load 9mm on my Dilon 650 for IPSC. i've been tweeking the crimp to get the bulge out of my loads. I'm using the Dillion carbide die set. my question is it normal to have a bit of bulge? or should it be like box ammo where the case is totally straight? I'm light on the case lube since it is a carbide die, some say I'm not lubing enough, that's what is causing the bulge. Some say the dillion dies makes a bit of bulge. I did the plunk test and measured on my block and no hang ups and length issues. thanks.

picture is the load with 147gr can pro seated to OAL 1.089
 
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The "coke bottle" shape is normal for the Dillon sizing die; it isn't a function of crimp. Somewhere around .375" to .378" is a reasonable crimp diameter for 9mm, the objective being to go just a bit beyond removing the case mouth flare.

If your rounds gauge and function correctly, your die setup is fine.
 
Dies it fit in your chamber? Then it's good.

There is no reason to use case lube with carbide dies. You are making more work for yourself by having to clean it off prior to firing the rounds.

Scott
 
Dillon told me it was normal, I believe it's because the powder funnel stem doesn't go as deep into the case as your regular die set. I don't like it on my competition rounds so I do my cases in two stages. I have a blank tool head and put a sizing die and my normal expander die in it. I run all my cases through that set up, and then run them through again with the main tool head finishing the rounds. It's not really necessary, but I don't mind the extra step for my competition rounds. Bulge is virtually eliminated.
 
Like the the two guys above said - it's good.

What's happening is the Dillon die is trying to "straight-wall" the first few mm of the case instead of leaving it tapered like 9mm Spec. (It's improving on the spec.)

If you're taper crimping (crimping at the case mouth) range brass; every brand can be different lengths and therefore the crimp can't be consistent.
With these dies doing this thing, you to get a more consistent crimp; having more of the case in tight contact with the bullet.

On my 1050, I actaully use a 38 Super die after the 9mm to straight wall the case even more.

PS - I case lube 9mm even though I have carbide dies. I find it makes cranking the handle easier. Anything to make reloading less drudgery is a good thing.
 
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Below is a 9mm cartridge "before" applying a taper crimp, the straight edge shows the flare at the case mouth and the wasp waisted case body.

pRVen2j.jpg


Below is the same case after applying a slight taper crimp, and you can see where the base of the bullet is and the wasp waisted case shows plenty of bullet grip.

MfcwIQB.jpg
 
I use a Dillion case gauge.

If it slides in flush and falls out on it's own when tipped over, it's good to go.
 
Dies it fit in your chamber? Then it's good.

There is no reason to use case lube with carbide dies. You are making more work for yourself by having to clean it off prior to firing the rounds.

Scott

x2.

The bulge you see is normal when the brass has been sized smaller than the bullet you are seating in it. If it chambers and function tests then it's good.
 
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PS - I case lube 9mm even though I have carbide dies. I find it makes cranking the handle easier. Anything to make reloading less drudgery is a good thing.

And worthwhile to note that cleaning up case lube isn't necessary with products like One Shot. I've reloaded and shot 10's of thousands (if not over 100 thousand) rounds like this with no issue.
 
I, too prefer to lube pistol cases to cut down on sizng effort. For the amount of lube that is required, you don't need to remove it from the loaded rounds. If you prefer to do so, it is quick and simple to put some loaded rounds on a towel, spray with brake cleaner or 99% isopropyl alcohol, and then grab the ends of the towel and roll the rounds back and forth.
 
Thanks for your post. I have the same setup as you, Dillon press with Dillon Carbide 9mm dies and my ammos look the same as yours. I was asking myself too if it was normal or not. From now I just won't bother with it anymore!
 
Throw away or trade the Dillon 9mm sizer. As you reload the same case over & over the Dillon die will swage the 9mm brass down leaving an oversize ring at the base that will be oversize in your 9mm barrel. Making the chambering impossible.

Buy a new LEE carbide 9mm sizer & install it. Higginson Powder stocks them.
 
The Lee Factory Crimp Die will mount nicely in the last station on your XL650 and make all the coke bottle curves smooth right out. Cheap insurance on the loaded rounds fitting any chamber too. Just make sure that your seating dies lock ring is tight so you don't get any too long OAL situations.
 
The Lee Factory Crimp Die will mount nicely in the last station on your XL650 and make all the coke bottle curves smooth right out. Cheap insurance on the loaded rounds fitting any chamber too. Just make sure that your seating dies lock ring is tight so you don't get any too long OAL situations.

This is what I use - the Lee FCD is cheap and does a great job of "finishing" the round. Very light crimp only needed.
 
The Lee Factory Crimp Die will mount nicely in the last station on your XL650 and make all the coke bottle curves smooth right out. Cheap insurance on the loaded rounds fitting any chamber too. Just make sure that your seating dies lock ring is tight so you don't get any too long OAL situations.

I use lee dies, including the factory crimp, and I get the same effect. 5000rds and never effected the function.

60293319_339855346722432_515640283065483264_n.jpg
 
The Coke bottle or wasp waisted effect on the resized cases is normal and increases the grip on the bullet. Lee even sells undersized dies that sizes the cases .002 to .003 smaller in diameter.

The cases are sized and then the expander opens the case back up closer to bullet diameter. The reason the die sizes the cases smaller in diameter is because brands of brass vary in thickness.

Another reason is as the brass becomes work hardened the more it is fired and sized it will "spring back" more after sizing and loose bullet grip.

Bottom line the cases are sized smaller in diameter so all brands of brass and brass spring back will not effect bullet grip and the bullets moving in the case.

Read the link below, Wobbly does a very good job of explaining what effects bullet grip.

Lesson in 9mm neck tension
https://czfirearms.us/index.php?topic=87504.0

Below undersized die that many shooters use with mixed range pickup brass.

Undersize Reloading Die, 9mm Luger
http://www.egwguns.com/smithing-tooling/undersize-reloading-die-9mm-luger/

Caliber: 9mm
Brand: Lee Precision

Our Dies are maufactured by Lee Precision.

If a die is available online to purchase, it is in stock. Due to high demand the inventory will be fluctuating constantly.

Extra decapping pins available here.

A must for the serious reloader: EGW offers custom designed, carbide sizing dies that are 0.003" smaller in diameter than typical dies. Not only is it smaller in diameter, the bottom corner is radiused which sizes the case further down. This helps prevent feed failures from cases that bulged near the base during reloading- which is typical of brass fired in Glocks and other loose chambered guns.

The dies are made out of carbide.
 
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