Sizing issue on.40

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F5guy

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I've been reloading .40 for years with 175 gr lead and recently switched to 180gr Missouri bullets lead. I use the same recipe and they function fine- the only change in my setup was I had to adjust the seating die just a hair to get same oal. I just randomly picked up a .40 case gauge and guess what, the new loads won't go all the way in but they fit in chamber and function perfectly. I had some of the leftover 185's and the fit the gauge perfectly. It appears there is a small bulge towards the bottom of the new loads. An clues on what's happening and how to fix? I use a Dillon 550. Thank you
 
Is this brass you bought as once fired? The first thought that comes to mind is brass fired from an unsupported chamber usually has a bulge at the head.. Such as brass fired in a Glock...
 
Whats the diameter of the lead bullets? They are probably around .401 and you said the 180's needed to be seated deeper so its most likely the bullet bulging the case. If they fit the barrel then you have no worries. Case gauges are basically worthless and with lead bullets even more so. If the sizer die is set up right and the rounds are test fit into the chamber then there is no need for a gauge.
 
they fit in chamber and function perfectly.
Then you don't have a problem now do you?

Fuggedabout the case gage!

But to answer your question.

Pistol cases are tapered toward the head to provide more strength.
Some brands more then others.

The heavier bullet seated deeper is getting into the case taper more and bulging the base slightly more.

No Problem if it 4-F's (Feeds Fires, and Functions Freely).

Caseweb.jpg

rc
 
Most of the brass is once fired from my gun Starline brand. I just think its strange since nothing else changed. I would understand if it were anwider diameter bullet but the oversize conditin is below the bullet. Were the bullet is seated fits perfectly in the guage. I could post photos but its imperceptible for certain. Anyone else have a clue?
 
There's one clue. :D
rcmodel said:
Pistol cases are tapered toward the head to provide more strength. Some brands more then others.

The heavier bullet seated deeper is getting into the case taper more and bulging the base slightly more.
 
Sounds like RC may have solve your issue. I tried some 180gr Lead boolits last year. After fighting with about 20 rounds I sold them, and went back to my Berry's, and PD's. All I shoot from my .45's is lead, but didn't care for lead in my .40's.
 
I have seen the exact same thing. My rounds fit the chamber but will not fit a wilson case gauge. The lead bullet is the culprit.

FYI
Glock is not the only pistol guilty of bulging.

As long as they cycle I shoot them and all of them cycle.
 
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Interesting info and thanks for posting I need to check the once fired empty cases to see if they are bulged prior. I'm confident I can shoot them but with no issues and will report back any findings. It was just a little in needing since I know some live by case gauges. The good news is I was forced to shoot my P99 in IDPA match today with factory rounds and it was fun as heck. I'll report back.
 
Some resizing dies like Dillon may have larger radius at the die opening and may not fully resize bulged cases down to the case base, especially if they were overly bulged in generous 40S&W chambers. Some use push through resizing dies like Redding G-Rx or Lee FCD/Bulge Buster.

For match loads that must perform, I resize/deprime the cases first and test them in my match barrels to ensure they drop in freely with a "plonk". If they don't, I attempt to resize one more time and toss/recycle if they fail again.

By using resized cases that passed the barrel drop test, you can avoid finished rounds that won't fully chamber during a match stage that will add several seconds to stage times to clear.
 
Problem identified and fixed. Crimp die was set too low and basically pushing brass down. Thanks for all the input but I just had to take a step back and really "look" at the problem and all the potential factors. Carry on....
 
Take a look at this before you get over confident ....

Over-doing the crimp can definitely cause a problem. However, here's a good article that shows why the .40 Cal. has more than it's share of case resizing problems.

Handloading the .40 Caliber

A case gauge is a very handy tool for making quality .40 Cal. handloads. You can also use your barrel as a gauge, just be sure your handloads fit flush (or below) in your barrel.
 
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