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9mm plunk test 50/50

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It sounds like the case is flared too much and not keeping the bullet concentric. Most of the time when we load out the 9mm to 1.150"+ we cant rely on the case to straighten the bullet when seating or crimping. The less flare you have, the less likely the round will bulge and seat cockeyed. As far as crimp goes, don't! I measure the bullet (.355) and case thickness (.011") times 2, the case mouth should measure .377"

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Plunk Testing:

The solution to chambering problems is to determine the cause:

Take the barrel out of the gun. Drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in barrel (or gage) and rotate it back-and-forth a few times.

Remove and inspect the round:

1) Scratches in the ink on bullet--COL is too long

2) Scratches in the ink on edge of the case mouth--insufficient crimp

3) Scratches in the ink just below the case mouth--too much crimp, you're crushing the case

4) Scratches in the ink on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit

5) Scratches in the ink on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.

Plunk test picture.jpg

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^^^^  This 1000 times!!!

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34 minutes ago, TimBoettcher said:

It sounds like the case is flared too much and not keeping the bullet concentric. Most of the time when we load out the 9mm to 1.150"+ we cant rely on the case to straighten the bullet when seating or crimping. The less flare you have, the less likely the round will bulge and seat cockeyed. As far as crimp goes, don't! I measure the bullet (.355) and case thickness (.011") times 2, the case mouth should measure .377"

Thanks!!! I'll take a look at the flare amount and fiddle with that to see what happens.

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8 minutes ago, Bench said:

Thanks!!! I'll take a look at the flare amount and fiddle with that to see what happens.

 

The less the better 😉

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34 minutes ago, noylj said:

4) Scratches in the ink on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit

5) Scratches in the ink on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.

Plunk test picture.jpg

Thanks!!! I"ve put so much marker on so many cartridges...on the bullet and crimped end...but never lower on the case(!!). I'll get to it once the coffee takes a hold. Then look into what's needed to correct anything that might show up as a result of issues you mention in #'s 4 & 5.

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2 hours ago, Bench said:

Thanks!!! I"ve put so much marker on so many cartridges...on the bullet and crimped end...but never lower on the case(!!). I'll get to it once the coffee takes a hold. Then look into what's needed to correct anything that might show up as a result of issues you mention in #'s 4 & 5.

Ok, here's what scratched off: What's a good next step for correction?

20190605_101020.thumb.jpg.0af19f08bce78aa98bddfd02d0d7f82e.jpg

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Your die might not be reducing the case body diameter enough, or you have a tight chamber. I would try a Lee undersized die that reduces the case diameter .002 to .003 more than a standard die.

 

The older cases become work hardened and spring back more after sizing. And range pickup brass fired in larger chambers can also cause problems.

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Just now, bigedp51 said:

Your die might not be reducing the case body diameter enough, or you have a tight chamber. I would try a Lee undersized die that reduces the case diameter .002 to .003 more than a standard die.

 

The older cases become work hardened and spring back more after sizing. And range pickup brass fired in larger chambers can also cause problems with brass spring back.

 

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45 minutes ago, bigedp51 said:

Your die might not be reducing the case body diameter enough, or you have a tight chamber. I would try a Lee undersized die that reduces the case diameter .002 to .003 more than a standard die.

 

The older cases become work hardened and spring back more after sizing. And range pickup brass fired in larger chambers can also cause problems.

I checked by resizing a case only and the case goes in and out of the chamber the way it should...drops in and rotates freely.

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I'd still try the Lee undersized die, cases should look a little more (wasp waisted) than your example appears to.

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1 hour ago, Steve RA said:

I'd still try the Lee undersized die, cases should look a little more (wasp waisted) than your example appears to.

Thanks Steve, I'll give it a go when I'm set up with Lee...

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Posted (edited)

Does your sizing die kiss the shellplate? It should. Raise the ram and lower the sizing die until it touches the shellplate.

Edited by 4n2t0

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Posted (edited)
Just now, 4n2t0 said:

Does your sizing die kiss the shellplate? It should...

Thanks, it does. That was checked yesterday when I assembled the reloader after cleaning all the accumulated schmutz. As I posted above, I can get a reduced resistance to the rotation with a shorter OAL. It's still there (softer) but better and closer to a full rotation. Off to the range soon. There's a steel match Friday but the Beretta isn't making the trip...

Edited by Bench

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Always check your die settings with a full (cartridge cases) shell plate.

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Just now, Steve RA said:

Always check your die settings with a full (cartridge cases) shell plate.

 

Just now, Steve RA said:

Always check your die settings with a full (cartridge cases) shell plate.

Thanks Steve RA, that's something I've not heard of before...good point!

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If the loaded cartridges enter and fall out of the case gauge without effort, would not worry about rotation, think they will enter and fall out of the barrel when firing.

Just test fire before the match.

Mark

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1 hour ago, mpom said:

If the loaded cartridges enter and fall out of the case gauge without effort, would not worry about rotation, think they will enter and fall out of the barrel when firing.

Just test fire before the match.

Mark

Thanks, that's kind of where I'm headed next...

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THANKS ALL for your replies! With all of the permutations of OAL and CRIMP there still was a bit of resistance to rotation even below safe OAL's so today I packed up and went out to the range with a variety of OAL's (safe standards) and CRIMPS and fired away ~200 rounds and no issues with going bang or especially KABOOM(!).

 

I'M JUST NOT GOING TO WORRY ABOUT IT, GRIP REALLY, REALLY HARD, PULL THE TRIGGER...REPEAT...

 

Thanks again to you all for chiming in!👍

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before doing the plunk test one should clean the chamber to remove any residue from past firings.  any buildup in the barrel  might keep the ammo from dropping free. same for case gauges. even a little oil will keep them from dropping free

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9 hours ago, Sandbagger123 said:

before doing the plunk test one should clean the chamber to remove any residue from past firings.  any buildup in the barrel  might keep the ammo from dropping free. same for case gauges. even a little oil will keep them from dropping free

Thanks. That was one of the first things I checked...repeatedly...

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Posted (edited)

From what I read, you have a Dillon Square Deal B press, if that is true then there is NO Lee undersized die for it.

 

But do this, push on the underside of the #1 (sizing die) and see how much it moves up and down, if it moves too much, you can make a shim (look like a washer) out of the primer tray sleeve and put on top of the die to reduce the upward movement, and make the case go up further in the die.

 

Also lubing the cases before sizing will help with the process and easier on your elbow, just have to do some cleaning of the completed rounds that's all.

 

.

Edited by Vmax606

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11 minutes ago, Vmax606 said:

But do this, push on the underside of the #1 (sizing die) and see how much it moves up and down, if it moves too much, you can make a shim (look like a washer) out of the primer tray sleeve and put on top of the die to reduce the upward movement, and make the case go up further in the die.

 

Also lubing the cases before sizing will help with the process and easier on your elbow, just have to do some cleaning of the completed rounds that's all.

  

.

Good thought on the shim, I'll take a look. One Shot is part of the routine, a little cleanup following loading needed though.

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16 hours ago, Bench said:

  I went to the range with a variety of OAL's and CRIMPS  ~200 rounds and no issues with going bang 

 

Great.   Problem solved.    :) 

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3 hours ago, Hi-Power Jack said:

 

Great.   Problem solved.    :) 

LOL, it's always great to solve a problem...that isn't a problem🤣

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