9mm Sizing Issue...?

[Saluki91]

I tried to load some 9mm on my XL750 today, but ran into a problem. My first case didn't pass the case gauge. After examining the offending case, it became clear to me that the bottom of the case is no longer properly sized. Cases tested after sizing alone pass the gauge just fine, but a case run through the press is no bueno.

Is it possible that the powder funnel is somehow expanding the base of the case? If so, that would be a first... but I can't come up with any other explanation. I have run umpteen rounds through these dies (Dillon) and this powder funnel (UniqueTek) with no issues. What in the world could I have done to create this?

Thanks in advance for any guidance you can offer!

Cheers!

 

[Hugger-4641]

Not likely that the base is getting swelled by funnel or press. More likely your bullet size, crimp, or case length is causing a problem.

 

[Walkalong]

My first case didn't pass the case gauge. After examining the offending case, it became clear to me that the bottom of the case is no longer properly sized. Cases tested after sizing alone pass the gauge just fine, but a case run through the press is no bueno.

So, no other function going on when you run a case all the way through using the sizer only? Or a loaded round vs a sized case?

A loaded round? See post # 2.

 

[drband]

I tried to load some 9mm on my XL750 today, but ran into a problem. My first case didn't pass the case gauge. After examining the offending case, it became clear to me that the bottom of the case is no longer properly sized. Cases tested after sizing alone pass the gauge just fine, but a case run through the press is no bueno.

Is it possible that the powder funnel is somehow expanding the base of the case? If so, that would be a first... but I can't come up with any other explanation. I have run umpteen rounds through these dies (Dillon) and this powder funnel (UniqueTek) with no issues. What in the world could I have done to create this?

Thanks in advance for any guidance you can offer!

Cheers!

Check your bullet seating/crimp die

 

[Walkalong]

Is it possible that the powder funnel is somehow expanding the base of the case?

It would have to go quite deep to do so. Will it?

 

[Saluki91]

It would have to go quite deep to do so. Will it?

So after re-checking my thrice-checked powder die, I suspect it was the following:
1 - The LOS 124gr JHP (.356") bullets I was trying to load required me to open the case mouth quite a bit in order to allow the bullet to sit in the case mouth properly.
2 - The powder funnel I am using doesn't put a severe "bell" in the case mouth. As a result, I had to turn it down quite a bit before the bullet was happy.
3 - In doing so, the funnel was engaging the case much deeper than with other bullets I have loaded. This was enough to cause the base to bulge.

I had to make minute adjustments with the powder funnel until I found its "happy place"... flaring the case mouth enough to accept the bullet, but not penetrate the case so deeply that it bulges the base. The "happy place" exists, but it is so very very tiny!

Rounds now pass the case gauge under mild protest... but they plunk and feed without issue.

Thanks for your help!

 

[Hugger-4641]

So after re-checking my thrice-checked powder die, I suspect it was the following:
1 - The LOS 124gr JHP (.356") bullets I was trying to load required me to open the case mouth quite a bit in order to allow the bullet to sit in the case mouth properly.
2 - The powder funnel I am using doesn't put a severe "bell" in the case mouth. As a result, I had to turn it down quite a bit before the bullet was happy.
3 - In doing so, the funnel was engaging the case much deeper than with other bullets I have loaded. This was enough to cause the base to bulge.

I had to make minute adjustments with the powder funnel until I found its "happy place"... flaring the case mouth enough to accept the bullet, but not penetrate the case so deeply that it bulges the base. The "happy place" exists, but it is so very very tiny!

Rounds now pass the case gauge under mild protest... but they plunk and feed without issue.

Thanks for your help!

Glad you figured it out. Having a little trouble picturing it in my mind since 9mm is a tapered case. The base is nominally 0.391" od and the mouth should be 0.380 before you flare. Guess I'd have to see it to know.

 

[mdi]

My first guess would be over crimping, causing the case to bulge. I do not "crimp" my semi auto handloads, just "deflare" with a taper crimp die. I don't use a case gauge either (I don't shoot my handloads through a gauge). I use the barrel of my gun(s) as a gauge. Any time there is a fit issue, measure. Measure the diameter of a finished round in a few places. Measure OAL. Look for bulging cases and/or cartridges too long...

Too much case mouth flare is when the case won't enter the bullet seating die. Any flare is removed with a deflaring die (aka taper crimp die) after bullet seating...

 

[chevrofreak]

Dillon 9mm seating dies are absolute trash and are likely to seat a bullet crooked. Get yourself a Hornady seating die with the sliding alignment collar and a Lee factory crimp die and you will rarely have a cartridge fail to gauge.

Also, if you are using a long heavy bullet like a 147gr you can run into problems of pushing out the case web if you seat it too deeply. This is a particular problem with truncated cone FMJ and JHP type bullets because they have to be seated so deeply.

 

[N555]

Crimp as a separate step.

 

[Soonerpesek]

and this powder funnel (UniqueTek)

What is the SKU of the UniqueTek funnel.....?

 

[lordpaxman]

Rounds now pass the case gauge under mild protest... but they plunk and feed without issue.

Oh no… time to dig out the FCD! Glad you found the issue, when I have problems like that it’s a “what’s changed” moment.
I use the AA/MrBullet feeder funnel and it works well - I suspect it’s very similar to the UniqueTek one. I haven’t had a problem where excessive flare crumpled cases and I need quite a bit when loading Blue bullets. Maybe the shoulder angle on the PTX is too steep?

 

[jmorris]

I have run umpteen rounds through these dies (Dillon) and this powder funnel (UniqueTek) with no issues. What in the world could I have done to create this?

So after re-checking my thrice-checked powder die, I suspect it was the following:
1 - The LOS 124gr JHP (.356") bullets I was trying to load required me to open the case mouth quite a bit in order to allow the bullet to sit in the case mouth properly.
2 - The powder funnel I am using doesn't put a severe "bell" in the case mouth. As a result, I had to turn it down quite a bit before the bullet was happy.
3 - In doing so, the funnel was engaging the case much deeper than with other bullets I have loaded. This was enough to cause the base to bulge.

I had to make minute adjustments with the powder funnel until I found its "happy place"... flaring the case mouth enough to accept the bullet, but not penetrate the case so deeply that it bulges the base. The "happy place" exists, but it is so very very tiny!

Rounds now pass the case gauge under mild protest... but they plunk and feed without issue.

Thanks for your help!

Ah ha, so it was a trick question. If you told us it all worked fine then you changed something, even I could have made a good guess.

 

[Saluki91]

What is the SKU of the UniqueTek funnel.....?

https://www.uniquetek.com/product/T1736

 

[Saluki91]

Ah ha, so it was a trick question. If you told us it all worked fine then you changed something, even I could have made a good guess.

That's just it - I don't remember changing anything on my 9mm tool head. Clearly something changed, but what it was still eludes me.

Fortunately, tweaking the powder funnel seems to have solved the problem for now... or perhaps I just wasn't holding my mouth right. ; - )

 

[Saluki91]

Oh no… time to dig out the FCD! Glad you found the issue, when I have problems like that it’s a “what’s changed” moment.
I use the AA/MrBullet feeder funnel and it works well - I suspect it’s very similar to the UniqueTek one. I haven’t had a problem where excessive flare crumpled cases and I need quite a bit when loading Blue bullets. Maybe the shoulder angle on the PTX is too steep?

The UT funnel doesn't really flare the case... it's more like a swage. It opens everything up so that coated bullets can sit in the case mouth and not have the coating shaved off during seating.

 

[Soonerpesek]

https://www.uniquetek.com/product/T1736

That's the one I guessed you was gonna say.............to me, it looks too long for 9mm case, but good for 38/357...............

I'm not looking to start anything, or dis the way you do things by any means, but what was wrong with the shorter Dillon powder funnel...............?

 

[Saluki91]

That's the one I guessed you was gonna say.............to me, it looks too long for 9mm case, but good for 38/357...............

I'm not looking to start anything, or dis the way you do things by any means, but what was wrong with the shorter Dillon powder funnel...............?

No worries at all!

I went to the UT funnel for two reasons:
1 - I wet tumble with stainless chips, so case sticking can be an issue. The Dillon funnel LOVES to stick to my cases (even more so with .45acp). The UT funnel all but eliminates the sticking.
2 - I was on the struggle bus when it came to Dillon's funnel belling/flaring the case mouth. It was easy to "over-bell" the case, and equally easy to under do it (thus shaving the coating off the bullets). Until this, I have never had an issue with the UT funnel.

 

[Soonerpesek]

The Dillon funnel LOVES to stick to my cases (even more so with .45acp).

Yeah......I think Starline sez something about that on their website....................I did shorten my 45acp Dillon funnel a bit to ease that, haven't had a problem since............

Looks like you got 'er figured out........Good luck n have fun............!

 

[lordpaxman]

The UT funnel doesn't really flare the case... it's more like a swage.

Both the UT and MrBulletFeeder are similar, at least looking at the pictures. They’re M style expanders, two steps, and an angled shoulder that flares/bells the case. What’s interesting about the UT is the length of the expander, and they have two different sizes, .357 and .358. I could measure the MBF I have, but believe it was .357” - it’s put away at the moment. Mine will definitely stick a bit since I wet tumble but I give the cases a shot of one shot.