Why does one 9mm bullet plunk and the other sticks

[rwsmith]

That's what I want to know....

"Plunk" or close to it is fine, but it's not necessary that they "plunk". What's more important than "plunk" is that they feed and chamber flawlessly 100% of the time.

...before getting to the range. The best test I have is plunking in a barrel. When I plunk factory ammo, it plunks solid and 99.99% of the time, works fine in any gun. I'd like to know why my reloaded ammo either plunks well, or is 'mushy' and DOESN'T work flawlessly 100% of the time. I'm not obsessing about plunking. My percentage of good 9mm ammo has gone way up because I've been dogging at it for years. But these inconsistancies seem to point to something I'm still not getting right when loading for semi auto pistol.

There's a BIG difference between plunking solid and being mushy enough to stick in the chamber when pressed in and needing a screwdriver to extract it.

I've gotten a lot of good leads here. Thanks to everybody.

Oh, BTW: One problem I have is that range brass varies a LOT, some I think are .380 brass but when I look at it it's clearly stamped '9mm Luger'.

 

[rwsmith]

I measured...

OP how did you determine your OAL? Did you just go with whats in a manual or did you measure it like Tazz666 mentioned?

I measured them.

 

[rwsmith]

Plunking isn't the issue...

The issue is that my 9mm ammo's reliability, though it has improved over time, still isn't near 100%. Plunking is the best test I have.

The first two things I'm going to work on are seating depth and minimizing the amount of crimp needed. Hopefully, that will fix the issue. If not, I've got a lot of hints to take it further.

Thanks again.

 

[rwsmith]

Nit picky?

Without looking at your loaded ammo, we are all just guessing. My guess is that your plunk problem is not the bullets you are using, but the brass. .......


*I am being nit picky here. It’s your AMMO that is failing your plunk test. Non shooters call loaded ammo “bullets”. Reloaders separate the 2 terms for clarity.

1) I gave a pretty good close up of the two cartridges side-by-side.

2) The reason I said 'bullets' is because both cartridges that I'm talking about are easily distinguished by the different color of the BULLETS.

3) In another post you say to measure case diameters. I provided the dimensions in my first post.

Thanks, however, for the comment about brass variability. That is indeed a problem.

 

[cracker57]

We are all trying to help you out here but you have not answered the question, How did you determine the OAL to load too.
If I am reading this right the red bullet is the one sticking and the other plucks and falls right out.
Also the red one is 4/1000 longer than the other. I would have to guess the longer red one is contacting the rifling before the case mouth contacts the chamber. If you push it into the barrel the bullet sticks to the rifling and you have to pry it out. what does the bullet look like when you pry it out does it have marks on it from the rifling?

 

[Yendor357]

The title of your thread said bullets.

You were dropping loaded rounds into your chamber. Not just bullets.

There is more than one variable in hand loaded ammo than just the bullet.

I’ll bet your projectiles, bullets, don’t vary nearly as much as the brass does.
When I have failure to chamber issues, it’s always brass; one particular brand. But I shoot conventionally shaped bullets. There is enough to go wrong with loading 9 mm that I won’t do a SWC shape to add to the issue.
You shove a bullet down into a 9mm case far enough, the body of the case will bulge. So the case mouth isn’t the only critical dimension.

Why do you ask my opinion, then argue with me? It’s just my opinion.

But you do you.

 

[zeke]

"OK, given that info, both of the cartridges plunk well in my Shield barrel. If I press on the gold bullet cartridge, it bottoms out hard on the rim in the chamber and drops back out when inverted with a little shake. The red bullet cartridge however plunks well, but sticks a little and if I press on it it feels like it's engaging the rifling (a soft lead feeling) and then I have a lot of difficulty getting it out with my finger nails and I have to wiggle the cartridge to get it out of the chamber."

My understanding of doing the "plunk" test is that the cartridge drops freely into the chamber till it rests on the chamber rim, and drops freely out when you invert the barrel. If you need to "press" on the cartridge to get it to seat firmly on the rim, or it sticks a little, the plunk test failed.

Couple of suggestions.

Follow the advise of using your tightest/shortest leade chamber to do the plunk test. There does appear to be a long length of full bullet dia out front of the rim.

Get a specific chamber cleaning brush to thoroughly clean the chamber

check that the bullet dia and that the crimped brass mouth is no larger than the brass with bullet seated in.

While some may scoff, there are advantages to separating brass by headstamp, which helps minimize these situations.

 

[youngolddude]

I took a factory round and measured it and set my OAL to that. It was 1.065." I set the seat die to measure .380" at the mouth and crimp die to .377." Those are all RN. Since you have a flat nose, I would load shorter than that, more like a HP. The rounds you show are close, so a small turn of your seater punch will get you there. The OAL you posted is an error.

 

[raljr1]

I just loaded a few hundred 9 mm. Oal for 124 gr rd nose was 1.150. i use a cartridge block and test about every 3rd or 4th one. Also loaded some 115 gr rd nose at 1.125. both rounds chamber and eject without issue in my 3913, my 39-2, and my Shield . After reading this I tried them in the Colt Pocket Nine...not so hot. I may have to go back and shorten then, or just shoot them in the Smiths

 

[Chubbs103]

I cast (and powder coat) my own for a number of calibers to include 9mm.

First, a word of caution. Adjusting COAL on 9mm can lead to to pressure issues. Make sure you take that into account as you work up from a starting load. I recommend a chronograph as well.

I am a firm believer in the plunk test, but it won't tell you everything about feeding. Use your barrel with the shortest leade. My Glock 19 barrel is generous and doesn't care where the bullet is seated. I have to be more careful with my H&K. Just a little too long and my "plunked" cartridges jam right into the leade. My H&K is my limiting factor, so I set COAL to keep it happy.

I typically load SWC profile (or others with a shoulder or driving band) with a very small amount of shoulder / driving band (between a thumbnail's thickness and 1/8") showing. Remember my caution about seating depth and pressure in 9mm.

I agree with everyone above that mentioned the brass. 9mm brass varies a fair amount brand to brand. I had the same headaches in "plunk" inconsistencies as you using mixed brass. I'm too darn cheap to consolidate down to a single brand. Through trial and error, I found that setting my dies for a proper plunk with Win brass, the other brands aren't a problem. If I set up my dies using one of the other brands, I can get a good plunk until I load a round with Win brass and it will force the bullet into the leade, just like you described.

 

[rwsmith]

Measured it with calipers..

We are all trying to help you out here but you have not answered the question, How did you determine the OAL to load too.
If I am reading this right the red bullet is the one sticking and the other plucks and falls right out.
Also the red one is 4/1000 longer than the other. I would have to guess the longer red one is contacting the rifling before the case mouth contacts the chamber. If you push it into the barrel the bullet sticks to the rifling and you have to pry it out. what does the bullet look like when you pry it out does it have marks on it from the rifling?

I did say that I measured them.

Yes, you are right, the red bullet is the one sticking. and yes I tore up my fingernails trying to pry it out. I found that if I wiggle it back and forth I could get it out without something to pry it out with.

The red one has already been pushed into the chamber (rifling) several times. It doesn't show any marks.

Thanks. Sorry, If I sound testy but that's for the people that comment without bothering to read the first post. I'm getting great info from a vast majority of the comments, as I'm accustomed to on this forum.

 

[Krogen]

I have a number of 9mm pistols, but one has a distinctly tight chamber. Some reloads don't plunk but are fine in other pistols. I found this out when I stuck a 9mm reload in the chamber. It stuck tight as it was helped along with the slide bashing it forward. The taper of the 9mm case made it stick like a cork in a whisky barrel. I had to bump the slide back by putting a flat-blade screwdriver between the barrel hood and the breechface.

9mms can be tricky to size. Are you using dies with full-length carbide inserts? Or some of the others with a short ring or two slightly different diameter rings? In my opinion the 9mm due to its taper is best sized with a carbide ring that's as long as the case. Or a plain steel die. Anything else is a bit of a compromise that may or may not work well in your gun.

Another poster suggested marking your case with a felt tip to see where the scuffs are when you have plunk problems. Good advice and it may point you to the problem.

 

[rwsmith]

Because it's insulting....

The title of your thread said bullets.

You were dropping loaded rounds into your chamber. Not just bullets.

There is more than one variable in hand loaded ammo than just the bullet.

I’ll bet your projectiles, bullets, don’t vary nearly as much as the brass does.
When I have failure to chamber issues, it’s always brass; one particular brand. But I shoot conventionally shaped bullets. There is enough to go wrong with loading 9 mm that I won’t do a SWC shape to add to the issue.
You shove a bullet down into a 9mm case far enough, the body of the case will bulge. So the case mouth isn’t the only critical dimension.

Why do you ask my opinion, then argue with me? It’s just my opinion.

But you do you.

I've been reloading for 40 years and I know the difference between a cartridge and a bullet. That is NOT the problem that I asked about. You could give your thoughts without being 'nit picky'. I do appreciate the information.

Maybe this is a good time to reset and start over, as we have not gotten off to a good start. I do apologize.

And yes, you are right, there is a balance between not seating deeply enough and seating too deep. But in case, with this particular bullet, I am going to try seating deeper than I have in the past. I believe that one thing that happens is when seated to the same depth, the shorter cases (unsorted range brass) will still have too much projecting and the bullet will still contact the rifling before the case mouth headspaces on the rim of the chamber unless I seat the bullets with the shoulder flush with the case mouth. But I intend to run a test with a large sample of cases with the methods that have been described in the comments. I believe I will add a few more percentage points to my reliability issues, hopefull approaching 100%.

Oh, I also believe from what's been said that I will need to do some brass sorting with maybe some rejection of way-out cases and maybe even doing some case trimming since my goal is high reliability. I mentioned in an earlier post that some 9mm Luger cases LOOK like .380 cases because they are so short but 9mm is stamped right on them.

One more thing for general info. Missouri bullets are amazingly consistent. I believe they size them after casting and re-size them after the coating is applied. The coating is also very consistant. They have perfected their application to a high degree. I had trouble with some early powder coated bullets from other manufacturers (lumpy texture) but Missouri is now my go-to. (Unsolicited endorsment )

 

[rwsmith]

Indeed!

"OK, given that info, both of the cartridges plunk well in my Shield barrel. If I press on the gold bullet cartridge, it bottoms out hard on the rim in the chamber and drops back out when inverted with a little shake. The red bullet cartridge however plunks well, but sticks a little and if I press on it it feels like it's engaging the rifling (a soft lead feeling) and then I have a lot of difficulty getting it out with my finger nails and I have to wiggle the cartridge to get it out of the chamber."

My understanding of doing the "plunk" test is that the cartridge drops freely into the chamber till it rests on the chamber rim, and drops freely out when you invert the barrel. If you need to "press" on the cartridge to get it to seat firmly on the rim, or it sticks a little, the plunk test failed.

Couple of suggestions.

Follow the advise of using your tightest/shortest leade chamber to do the plunk test. There does appear to be a long length of full bullet dia out front of the rim.

Get a specific chamber cleaning brush to thoroughly clean the chamber

check that the bullet dia and that the crimped brass mouth is no larger than the brass with bullet seated in.

While some may scoff, there are advantages to separating brass by headstamp, which helps minimize these situations.

...That is what's happening. My reloaded ammo is unreliable and the failed plunk test shows that something is wrong, at least for some of the reloads.

Yes, I'm going to check all of my 9mm barrels (oh my mercy) to see which is shortest/tightest.

The chamber brush is a good idea. I'll have to find one.

I'm not scoffing at the brass sorting idea, it's easy to see that the variability in range brass is contributing to the difficulty.

The bullets are very consistently .356" dia. I'm pretty sure that isn't the problem. But I'm just as sure that my crimp needs to be adjusted.

 

[rwsmith]

Maybe that's part of my problem....

I took a factory round and measured it and set my OAL to that. It was 1.065." I set the seat die to measure .380" at the mouth and crimp die to .377." Those are all RN. Since you have a flat nose, I would load shorter than that, more like a HP. The rounds you show are close, so a small turn of your seater punch will get you there. The OAL you posted is an error.

I checked several and that's what they measure. Why do you think it is an error? I'm going to seat them deeper so the final OAL should be about 1.075" (guesstimate).

 

[Chuck Edwards]

I checked several and that's what they measure. Why do you think it is an error? I'm going to seat them deeper so the final OAL should be about 1.075" (guesstimate).

I wouldn't worry about a specific OAL. I'd just make up a dummy round and seat it progressively deeper until it works, and let the OAL be what it is. This might have been what you meant and I misinterpreted.

 

[mtgianni]

Most people say we are nuts to load 9mm as you can buy it for yada yada yada. They say we must be crazy to mess with cast also. So given that we fall in the small percentages of those who reload 9mm with cast go the next step.

Sort all your 9mm casings by brand. That will eliminate much of the weight differences and keep thickness regular. I use old Costco nut jars for mine. I don't separate Winchester from WW or Super X, just by manufacturer. I toss the small amounts I get off oddball brass. If I have less than 50 I rarely keep it, or I shoot it and leave it at a range box.

When I load I currently use the same loads for Remington, Winchester, Federal and Hornaday but I only take one brand to the range at a time.

If I have a problem it is much easier to find out why with sorted brass. I don't think anyone is anal enough to trim 9mm but there's probably someone somewhere.

 

[zeke]

...That is what's happening. My reloaded ammo is unreliable and the failed plunk test shows that something is wrong, at least for some of the reloads.

Yes, I'm going to check all of my 9mm barrels (oh my mercy) to see which is shortest/tightest.

The chamber brush is a good idea. I'll have to find one.

I'm not scoffing at the brass sorting idea, it's easy to see that the variability in range brass is contributing to the difficulty.

The bullets are very consistently .356" dia. I'm pretty sure that isn't the problem. But I'm just as sure that my crimp needs to be adjusted.

BROWNELLS BRONZE HANDGUN CHAMBER BRUSHES

BROWNELLS STAINLESS STEEL REVOLVER CHAMBER BRUSHES

Whenever am trying a new bullet in 9mm that is intended to be used in any of the ones owned, do a plunk test in a CZ-75 compact that has the shortest leade of any owned.

Crimping with a LFC also helps with brass that vary in length/brass thickness.

Will admit to giving up trying cast in 9mm (with one target pistol exception using coated) due to the varying bore/groove diameters affecting accuracy/leading.

 

[rwsmith]

Thinking about maybe trimming....

Most people say we are nuts to load 9mm as you can buy it for yada yada yada. They say we must be crazy to mess with cast also. So given that we fall in the small percentages of those who reload 9mm with cast go the next step.

Sort all your 9mm casings by brand. That will eliminate much of the weight differences and keep thickness regular. I use old Costco nut jars for mine. I don't separate Winchester from WW or Super X, just by manufacturer. I toss the small amounts I get off oddball brass. If I have less than 50 I rarely keep it, or I shoot it and leave it at a range box.

When I load I currently use the same loads for Remington, Winchester, Federal and Hornaday but I only take one brand to the range at a time.

If I have a problem it is much easier to find out why with sorted brass. I don't think anyone is anal enough to trim 9mm but there's probably someone somewhere.

...just the extra long cases and discarding the short ones to have a good working range.

 

[rwsmith]

I did the testing and believe that I have it....

I got a sample of 20 cases and measured their length. The shortest measured 0.734" and the longest 0.749".

I pushed the cartridges with a loose bullet into the chambers of my 9mm pistols and measured them. It was a tough getting good measurements because the bullets were a little loose but I came up with a maximum OAL of 1.062". See attached picture Of cartridges, one short case and one long case.

I then raised the bullet seater on the die and lowered the die until the crimp was perfect. It just happened to be where my die was set, so it was fine for the batches I just made.

I think that this this would be good for anybody having problems with semi auto cartridges.

THANKS to everybody. I think that I finally have this problem solved.