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Steve Steven
02-16-2016, 09:11 PM
About 30 years ago, I was heavily involved in three-gun American Pistol competition, and reloaded all of my .45ACP ammo. One day,I had reloaded about 200 rounds, and went to the club to practice.

When I started shooting, in the first 10 rounds, I had a squib load, bullet got out oft he barrel and hit the floor before the target. Reloaded and tried again, bullet stuck in the barrel. Packed up and left the range. Got home, checked my press and found a dead bug in the powder measure. Press was(and is still) a CH MkIV Autochamp. Fixed that, but what to do with my 197 rounds of suspect ammo?Too cheap to waste it, too lazy to break it all down.

To make a long story short, I was bemoaning my problem at the next club meeting, when a buddy told me he had just what I needed. It was a sensitive microphone with a speaker. You shook the case in front of the microphone and if there were powder in the case, it would rattle and the speaker would sound it. You could even tell if there was only a small amount (say 5 or 6 granules) or if it was full. I used the device and checked all of the suspect lot, found several questionable rounds, opened them wirth an inertia puller, found that they were not fully charged, agreeing with the device. I later fired all of the lot, but not in competition, it all functioned the gun fine.

My point is this: The buddy with the microphone device is dead, and I haven't been able to find something like it on the internet. And sure enough, I did itagain, loaded a lot of ammo that I had a stuck bullet in the barrel. No bug in the powder measure, probably just my fault. I would like to get or make a similar microphone device so I can check out the rest of the rounds I loaded. Anyone here with sufficient electronics experience to design one for me, I can build one I am sure, I just don't have the knowledge to put together all the right parts (preamp, amp, speaker,microphone etc) in the correct order. Itwould be nice if it could be plugged into the microphone port on my laptop so I wouldn't have to get as much stuff, and use my laptop for something besides perusing the internet.

Anyone here that could help me with doing this?

Thanks for reading this,

Steve

bangerjim
02-16-2016, 09:36 PM
In the MANY years and MANY thousands of rounds I have loaded, I have NEVER had an over/under filled case.

I do each one by hand and set a boolit in the freshly filled case. No way can I have one not filled.

Just do you due dillagence up front and you will never have a problem.

What you proabaly need and could use is a clock beat amplifier. It is a very senstivie CONTACT microphone that feeds a solid state amplifier. I have several of them I use in my antique clock hobby.

Check out www.merritts.com.


bangerjim

blikseme300
02-16-2016, 10:09 PM
There are 2 kinds of reloaders, those that have had squibb loads and those that will, just keep loading long enough. I thought I was bulletproof once but then I got out of my twenties.

rancher1913
02-16-2016, 10:16 PM
use your scale. probably 4 or 5 grains of powder so you should be able to "see" an empty.

3006guns
02-16-2016, 11:23 PM
I had the same problem, but from a different reason.

I had a one gallon bag about half full of loaded .38 S&W rounds and was about to load fifty or so cases that I found in a drawer. I set everything up, set my measure with my scale for the correct charge of Unique and loaded all of them. When I went to put everything away I discovered.......to my horror......that I had grabbed the wrong can of powder....Bullseye! In other words, what would have been a "normal" Unique charge was certain death with Bullseye in my old Smith and Wesson. Since I had tossed each freshly loaded round in the bag as I went along, I had NO idea which were faulty.

Please, no comments about paying attention and verifying components. I felt dumb enough as it was.

Weighing was out.......the charge weight was the same anyway. Nope, I HAD TO PULL EACH AND EVERY BULLET IN THAT BAG UNTIL ALL OF THEM WERE EMPTY, THEN START OVER. With the correct powder this time. Even to this day I look at that bag and wonder "I DID get them all, didn't I?"

Bullwolf
02-17-2016, 01:23 AM
Try using a doctor's stethoscope?

I have a relative who swears by the powder shake method.

He won't even load some combinations unless he can have enough airspace to hear powder shake in his cartridge. One combination that comes to mind was a medium charge of IMR-3031 in non military .223 or 5.56mm cases.

This same relative once gave me a whole container full of the same head stamp of military 5.56 brass that had less internal case volume than the commercial 2.23 brass he was using, because the cases made a compressed load using his combo of powder and components. They made it so he couldn't "shake" to hear the powder in them to verify that they were loaded.

I prefer caution to the point of near paranoia when loading, and being darn sure that each and every single case is reliably charged with powder rather than using the shake test.

I often use full case density loads, or even compressed powders. So the shake method probably won't ever work well for me. It's also likely that I can't hear well enough to trust such a method at this point.

I have to relate an incident though that happened to the relative who liked to "shake" test his rounds to hear the powder.

He was pulling down some suspect rifle rounds looking for squibs, while doing the shake and listen for powder thing. He found one cartridge that sounded "funny" but still somewhat passed his shake and listen test, only something seemed wrong with this one particular cartridge.

I talked him into pulling the cartridge, since he wasn't 100% sure about it.
(When in doubt, pull it!)

The cartridge contained no gunpowder, but was ½ full of dirty... Tumbler Media! Corn Cob, or possibly even Walnut shell.

I've never quite let him live that one down, and I still won't shoot his reloads.


- Bullwolf

jmorris
02-17-2016, 10:10 AM
Brass weights will vary enough weight won't work. After the first time I would have suggested a powder check die.

dudel
02-17-2016, 10:42 AM
Unfortunately, I think the safest way is to pull them down. Maybe it's the reloading universe's way of doing penance for not paying attention to your loads. Pull 100 rounds, and you'll not want to repeat that again. You WILL check each round for powder!

dudel
02-17-2016, 10:42 AM
I've never quite let him live that one down, and I still won't shoot his reloads.
- Bullwolf

I'm not sure I'd even want to shoot next to him!

Steve Steven
02-19-2016, 07:29 PM
Well,
It looks like there is no one who can help. Thanks for the comments, I'll have to look elsewhere for electronics help.

BTW, I tried a mechanics stethoscope and I could hear the powder faintly rattling in the case of a 38spcl wad cutter, but it was difficult to hear and not near as distinct as the one I used many years ago.

I can see many microphones on the internet, just not sure which one I should try.

Thanks for the comments,

Steve

bangerjim
02-19-2016, 08:41 PM
Remember, this is a gun and loading forum, not an electronics forum!!

Well, I am an electrical engineer, a analog/digitalsound and music recordist, and have much experience in audio circuit design and usage, and I would say you are barking up the wrong tree. The only thing I can recommend is buy that clock beat amplifier set-up I suggested. It is extremely sensitive to the slightest sounds because it is a contact mic, not a normal voice mic like you are probably think about. I would never use a voice mic due to audio feedback problems you will constantly encounter.

banger

dragon813gt
02-19-2016, 08:51 PM
Brass weights will vary enough weight won't work. After the first time I would have suggested a powder check die.

If you weight sort in advance you can do it. The bullets would have to be weight sorted as well. Seems like the OP needs to do this because the other reloading practices are lacking.

JonB_in_Glencoe
02-19-2016, 09:22 PM
"music recordist" ...I had to Google that.

Steve,
I am a Electronic Technician, But my weak suit is Audio. But I can say, what you describe (sensitive mic and speaker), I would suspect if you don't buy something specifically designed to your needs and just buy any old sensitive mic, amp, and speaker, with the gain you'll end up needing, you will likely be listening to a lot of distorted noise and excessive feedback.
Thats my 2¢
Jon

jsizemore
02-19-2016, 09:54 PM
I would think a vocal microphone would do the trick. Probably a condenser or large diaphragm would be the most sensitive. I'd go to a musician's store to audition the various types. Many are adapted to recording directly to a computer file. I sent my sister a flyer from Parts-Xpress for a portable recording setup so she could do audio file narrations at home. You may be able to find an adequate mic at a pawn shop.

bangerjim
02-19-2016, 11:59 PM
If you go to a guitar/music store, look at CONTACT microphones, not voice microphones. There is a whole science to audio pick-up and amplification. Not simply pluggin an old cheap tape recorder mic into some old audio amp. I have been doing this audiophile/engineer thing for over 40 years.

If you get into high-end USB mics, you will not find the ultra-sensitivity you will need and they are very $$! I have a couple of them. They are specifcially tuned and designed for precise and accurate studio recording of human vocals and acoustical instruments.

Good luck. Your best bet is just insure you load all your cases correctly in the future and never have to worry about some silly microphone test!!!!!

OS OK
02-20-2016, 03:17 AM
"Hey…you screwed up right? Take the rounds down and pay your penalty for your mistake. Next time you sit at the press, I guarantee you will pay attention to every detail because you won't want another 'disassembly day' in the shop! We all do something that's hard to back out of at one time or another in life…you ain't alone!
Shaking those rounds to hear powder won't tell you anything but that there is something in there, that's all, certainly not how much of or what it is. There is too much weight difference between different brass mfgrs. all at different case lengths and then there is the rounds themselves…how much variance is there in the rounds themselves? Too many variables.
Yep…go ahead and frown...take them down."

Steve Steven
03-26-2016, 05:00 PM
Well,
I found what I needed. Following some of the comments here, I found a acoustic guitar pickup and an amplifier like this:
164569
http://www.ebay.com/itm/P007-Piezo-Contact-Microphone-Mic-Pickup-Guitar-Violin-Banjo-Parts-/261313025377?hash=item3cd7785561:g:DF4AAOxyBXNSZ-Ps

http://www.ebay.com/itm/JOYO-JA-01-Mini-Guitar-Amplifier-AMP-MP3-Input-3-5mm-with-Earphone-A4M5-/141936657600?hash=item210c1584c0:g:ZMMAAOSwHxVW8La k

From China, less than $20 for both. They came with ear buds, which eliminated the feedback problem.

The pickup has a female jack, which the amplifier plugs into. The amplifier is rather rudimentary, has no adjustments at all. The same company makes a JA-03 version which has adjustments, which maybe would have been a better piece to use.

In use, you plug the pickup and amp together, put on the ear buds, put the round on the pickup (I removed the twosided tape) and rock the round and listen. The sound is a faint "Swosh-Swosh) noise, I checked with a dummy round, there is a definite difference.

164581

I found no empty rounds, so I will shoot them in practice.

Steve

rpludwig
03-26-2016, 05:12 PM
I would not rely on anything other than pulling the rounds, just my opinion...

dikman
03-26-2016, 06:00 PM
This will really only tell you whether or not there is powder in the case, not whether you have a reduced load (unless you have extremely well-calibrated ears!).

mozeppa
03-26-2016, 06:10 PM
sorry....but if yer too lazy to break them down......(i broke down 40,000 over several months)

and....you are not careful enough to keep your mind on what yer doin.....


maybe reloading isn't what you should be doing!....you are ticking bomb waiting its turn to blow up in your face!


best wishes.




p.s. the 40k break downs were my deceased fathers......i trust nobody.

troyboy
03-26-2016, 07:02 PM
There was a time when the world was belived to be flat. Embracing new and evolving technologies is a good thing when they are used in practical application.

jeff423
03-27-2016, 08:46 AM
Thanks Steve. What a good idea. I normally use a indexing progressive with a powder check die so missed loads aren't a problem, but there have been occasions where this would answer a question. I'm going to get one of these.

ASM826
04-07-2016, 10:38 AM
I haven't (yet) had this problem, but I had a friend with a Dillon that was loading .45ACP and let the powder hopper run out. The empties were mixed in with the good. This method would have helped him a lot. Because what he did was shoot them, slowly, using the whole lot for single shot/first shot from the holster for time and accuracy. He kept a brass punch on the bench for the occasional squib.