Dang that stinks. They had one bulk packs before I announced this project haha. Good news is they still have a few thousand of the yellow tipped m183s. For whatever reason they are more expensive. May call Sean and see if we can get them for the same price as the reds.

Just a heads up that some of these are not point detonating. Some are only tracers. If you look at the upper left cutaway you can see that it's a tracer with some sort of compound that will be ignited at some point but it's missing the entire fuse assembly.

Those are the m181 and m182 time delay aerial burst rounds and will require a different style 40mm projo that i haven't transferred from my head to CAD yet.  The 183 projos are the point detonating ones. The easiest ways to tell the difference is in the base, as the time delay rounds have a clear green film on that seals the delay composition. They are also stamped on the nose with I think a 3 or 6 to denote 3 second or 6 second delay.

I will say that you should I understand be very cautious with the time delay rounds. Since the spotter charge is in the middlenof the body, it tends to rupture the lead body and throw it out in a few big chunks. While the m183s pretty much just throw the spotter charge out the bottom of the projo with no shrapnel or anything.  You are also shooting a huge lead slug into the air if you use the m181 and m182 as intended.  

I don't know the difference between the red and yellow tipped m183s. Or if there is a difference

Ok i did some more reading on cartridge collectors forums.

Looks like the yellow tipped m183s are probably from a hotter launch charge. I'm not an artillery guy by profession, but it seems there were multiple loads to simulate the variable powder charge of a real howitzer.

Found some really cool images as well. I've seen the 20ga adapters for m203s and m79s that are rifled and intended to be used with these rounds, but this is an actual military issue (non-US I assume) subcaliber kit to use these in an M79.
Attached File


And here are some cool cutaway images, like posted before. I wonder if the m183 uses a standard m55 stab detonator like used in the m550 fuzes for HEDP rounds. As thats the only part I'm missing from my m550s...

Attached File

Attached File

That last picture is of an earlier type of artillery sim with the same concept.

I looked at mine again.

Orange is the airburst. It looks really close to red. My sectioned airburst is yellow/red and has "tracante" on it.. So Italian?

Red and yellow are both PD. You are probably right about them doing different charge weights.

Orange/Red, whatever it is lol. I guess it is closer to red. For whatever reason it is the same on both my time delay and point detonating.  Wish i could find a supply of the spotter tracer projos. Though I'm working that from a different angle. I designed a new projo today that should work well with the time delay version

Like you mentioned earlier, the timed has a green film over the tracer segment. The PD has the black plastic cap. The orange timed and red PD is really close but distinct on my samples.

It's a small world!  I came up with the design for the aluminum pusher years ago and machined up a bunch.  Sent some out to some guys from the GROG 40mm community and I guess they filtered down to you.  I also made a batch out of nylon but they would not stabilize, with or without orange float.  I started out with the zinc pushers and they just don't work.

The first design was a closed base and worked like magic, but also had a nasty habit of launching the pusher back at me every so often.  One missed my leg by just a few inches and I went back to the drawing board.  Version 1.2 had a hole drilled in the pusher to let the sim vent but glue wouldn't hold reliably.  Version 2.0 had a sleeve that the sim was glued into and the butt end unobstructed.  Better but same problem.  The design you have is hopefully a 3rd iteration with an encapsulating threaded ring that holds the sim in the pusher.  It also allows the spotting charge, which is black powder, to vent unobstructed without having to glue in the sim.  The vented pushers can be used with the timed delay sims as well since they are exposed to the lift charge.  If you pop off the black cap with the green film there is a 100% detonation rate with the time delay sims.

I like what you've done with the printed pusher as it will allow for a higher velocity.  I played with the sims out of a 20G rifled shotgun and loaded them to different velocities.  Basically the faster they are going the easier they are to detonate.  Out of the launcher it takes a solid flat hit to detonate, soft earth berm or glancing hit wouldn't reliably cause detonation.  Really need to hit something solid.  With the shotgun I could get them to detonate on just about anything except cardboard/paper.  This was at velocities just under 800 fps.  FYI, initially I had a ported shotgun barrel and if you push them fast enough the velocity drop just after the ports will cause them detonate in the barrel(always wear eye protection, and don't use a ported barrel! :-) ).  

The arming velocity is 100 m/s, anything less than that won't arm the setback safety.  I had my share of UXO and the thing to remember is that they are point detonated so as long as you don't drop them on the nose they are safe.  Treat the butt end of the sim like a loaded gun until rendered safe.  Can be rendered inert by soaking in water, placing them in a bucket and covering in water for a week.

I did all of my testing at a private range and was very careful to police up all sims.  I don't think I could get past it if a kid picked up one of these and had an injury.

SGT-Fish:  My comments are not directed to you about safety.  I have followed your threads for years both here and on the GROG's forum and respect the cool things you have done in a safe and responsible manner.  Just trying to mimic what everyone has done which is to give as much info as possible to keep the community safe and informed.

Please PM me if you would like to talk about your project off line.  Happy to share more details.

Thanks for this info. I posted this idea probably 5-6 years ago on subguns, and someone replied that they had already done this and had a couple hundred of the pushers to sell. I won't say who cuz people may bombard them with emails. But they were great and sent me everything to load 10rds for a great price. The versions I received require the sim to be epoxies in place. I had trouble with the epoxy failing cuzbj didnt use enough, and the sim would fall out and I'd have to drop it in a bucket of water for a few days. Then, after adding lots of epoxy, I had trouble with them not arming, possibly because I wasn't using a sealant to seat the projo in the case, or maybe I wasn't hitting hard enough targets. One of the video clips is of one of your original pushers. I shot it through my break action launcher with the 14" barrel for better velocity. That was the only shot I ever got to work, before I decided to try printing them. I did send one pusher to Scot Pace to have him take a look, don't think he has done anything with it, but he suggested putting a plastic driving band on them to decrease barrel wear.

I will PM you later as I would love more details. I hope with 3d printing, I can design a stable, open source solution that only throws some lightweight plastic around at the worst.

Yep, I sold that guy both types.  Sounds like you have the older design.  

I really like the direction you're going with these.  It seems like such a waste of good aluminum.

The pushers are 6061 so totally safe of the barrel rifling.  Hardness is less than the zinc.

Years ago I saw a very similar kit for the M203.  Haven't seen one again.  Very expensive for what it was.



Just looked it up.  $850.  There is a kit that works on the 12 inch M203 and M79.  Then there is a kit for the 9 inch M203.

That's the subcal kit that I have. I got it about 15 years ago and I believe that I paid $350 for it. I have the 9" but I'm wondering if I shouldn't have gotten the 12" instead as I have a high failure rate due to what I believe may be the projectiles not stabilizing and tumbling. Or maybe the latest batch of projectiles I have are defective. That's why I'm looking forward to trying these in in some sort of 3D printed projectile. BTW, that adaptor is heavy. It turns your rifle into a boat anchor.

I have designed some new projectiles in the past few days.

1. Airburst capable w/cavity
2. Impact w/cavity
3. Impact w/ cap and cavity. Allows for easier loading of chalk, skittles, etc.

Rest of the test prints are finishing tonight for fitment and will be ready to go.

jrpett,

I almost bought one of the autoweapons adapters but went the 20G pump shotgun route instead.  The sims I picked up were wrapped with electrical tape and then loaded in the 20G shell.  
I can imagine there could be inconsistency in the seal so that may be what the problem is.
I had looked at ordering a 14.5mm rifled barrel and reproducing the cases but had so much fun with the shotgun I didn't pursue it.

Ended up disassembling the rounds and shortening everything enough to get them to cycle through the shotgun.
Working the action as fast as I could put a smile in my face.

Yeah, I remember we had a pretty good discussion going on over on Grog's forum about these. Lots of info and ideas were discussed. I tried electrical tape too and and was never able to find a foolproof way to get them to work consistently through that adapter. I've been out of it for awhile so I feel like I'm going to have to start from scratch all over again. In the meantime, I'm really tempted to get something like this. Being that the loaded rounds are long, I think this would be the easiest solution. But ultimately, I want to get this working out of the M203, and I'm really interested in what's being done here to allow them to be fired from an actual 40mm round.

https://cva.com/product/hunter-20-gauge-rifled-slug-blued-with-black-stocks/

You guys are a terrible influence. Ordered 50 arty simulators to start. I'll see if modified nose cones were in that zip file or not. Time to start printing. I am guessing the chalk loads were absorbing some of the impact, causing them to not detonate reliably.

Where did you get the cutaways? Didn't see them on the site.

Recompiler, check your email.

Sorry I haven't gotten an updated range report. Even in Ohio the snow and cold are keeping me inside, as well as a pregnant wife and a DIY shower remodeling job. Weather is breaking this week so I'll get some testing done.

Thank you. Replied yesterday. I'm in PA so essentially same weather. I will start printing the designs next week and hopefully have arty sims for testing week after next. I'd love to combine the arty sim with glow sticks goo. Impact with glow would make my day, and be more useful than any commercial round.

Do you think a projectile containing more than one would be feasible or too heavy to achieve the necessary velocity for detonation?

I think it would be too heavy for a standard m781 blank.

I think if you have more than one projectile, and enough powder to launch them a resectable distance, the round itself will cross over into DD territory. We can mock it up easily with lead weights instead of submunitions. I am printing a batch with glow in the dark plastic for 1 submunition now based on the shared files. My submunitions get here Thursday if UPS doesn't screw up again. I am planning to shoot Friday night.

Correct. More than one of these projectiles and you're almost certainly over 1/4oz for the total. The total 40mm payload is what the ATF considers when determining DD or not.

One of my helpers measured the spotter charge at .9oz. Not including the detonator. So you may get away with two.

The launch charge is not part of the calculation

While the ~5-7gr of Bullseye isn't huge either way I don't think they count it as payload. If they did then a lot of sub-.50 bore cartridges would be DD right off the bat! Hell - 20x102mm is generally loaded with north of two ounces of powder. Even .50BMG is over half an ounce usually.

Detonators however - those are launched. I think they do actually figure into the 1/4oz explosive limit.

ETA: This discussion finally got me to order a handful of the projectiles. I might as well have actual on-hand samples if I'm going to recreate them.

2 won't stabilize, 4 or 5 might work with 100% infill. Someone with an explosives manufacturing license should give it a shot.

This is very cool. So where does one acquire these M183 sims?

CDVS and sometimes gunbroker.

I have test vid 3 almost ready to out out. Still not getting the results I want. The airburst version needs some heavy revision as most came apart in the barrel, point det version is really acting weird. I'll get good detonation on trees and even the ground, but hitting 3/4 inch plywood seems to not set them off, maybe its too springy? Either way it warrants more testing. They seem to be flying straight though

The PLA used also makes a bit of a difference.  The overture matte pla seems to print awesome and doesn't separate at the layers. It feels as if its a solid piece of dense plastic, almost has a clay pottery feel to it. Some other PLAs didn't hold up as well and could be a contributing factor.  

Wife and I took a spontaneous vacation to Florida, so ill get back at it next week. Also finally starting to print some glock frames since a coworker was interested in the possibility

CDVS at $3/each. Shipping a handful wasn't awful but I'm right next door.

Well look at how much the detonators have to move to actually impact the FP. They're not exactly designed with a hair trigger. I wouldn't be shocked if that's all it is regarding the plywood.

I'm not surprised at all about the time delay projectiles coming apart. I wonder what the RPM is at the FPS you're sending them. I haven't yet found any reference to the twist on the various trainer barrels for these but with such a thin lead jacket I bet it's not exactly a tight twist.

ETA: I'm an idiot.

Assuming 300FPS or so that's only 4500rpm.

That can't be the issue. Twist rate of the usual 14.5mm barrel is about 1:18" and even at 300FPS that's 12000RPM. Did Germany use some oddball extremely slow twist?

Or - again realizing I'm an idiot - did you mean that the printed carrier for the time delay projectiles is coming apart in the barrel?

ETA: I found the actual twist rate used! 1:42.35". Again assuming 300FPS that's 5100RPM in the 14.5mm versus the 4500RPM of the 40mm. Source 100% incorrect. No way. I did a quick stability calc just now - nowhere near.

The original cartridges were designed to launch the various projectiles at 330-445FPS depending on charge.

Want to risk AR500 steel plate? That should point detonate

My experience with these out of a 40mm launcher is that the velocity isn't enough for soft targets.  I couldn't get reliable detonation in something as solid as a refrigerator door or a soft berm.  Once I stepped up to a 20G rifled slug barrel it would go off hitting about anything.
The sweet spot for me was 700 fps out of the 20G.

I don't know why the lighter delrin pushers wouldn't stabilize but my assumption was that the CG was too far forward and they would swap ends and destabilize.  Someone smarter than me may be able to speak to this.

That's a great find!  On my list of must have's.

Good luck trying to find one though. Everywhere I look says out of stock or backorder. Looking on Gunbroker, even trying to find any break open 20 ga rifled barrel shotgun from any manufacture seems to be difficult. And when you do, the prices are way up there.

To any of you guys that have printed some 3D projectiles, would it be possible to host these files somewhere for download or would it be possible to have them emailed to me? A friend just bought a 3D printer and I'd like to have him print up some projectiles to try.

Thanks.

Ctrl+pew offered to host them. I need to write up printing instructions and convert the files to .step for him. Funny thing is that they are stl files from the beginning because I made them with tinkercad

If anyone has emailed me asking for them, try again or try my other email jacob.jtek@ gmail dot com

Sometimes I forget to reply or it goes to my spam.

I looked on CVDS website and I can't find them. None of my searches for M183 or sim, etc. revealed any results. It could just be that I'm an idiot but where on the site are they located? Or is this something you gotta contact them for? Thanks

Under 14.5mm

Arty sims

Here you go.

ls sent to those that have reached out. If you didn't get one, email me again...

Email sent.

OK DUDE.

You're a jerk for making me have to learn about and calculate the cost of getting into 40mm.

It's better to not calculate. Just do it

I had a thought about these arty sim rounds.  I am wondering if they can be adapted to a soda can launcher.  What say the hive?

For those of us who also own a mortar, I am guessing it wouldn’t be legal to bore out the middle of a dummy round & glue a 14.5 sim in there?

I am pretty sure that's how you get the soda can upper reclassified into a DD

Possibly.

Also, for mortars, you are better off with shotgun shell spotter charges

Anybody know if these even worked?
https://www.cdvs.us/product/m79203-metal-pusher-with-14-5mm-point-detonating-or-air-burst-projectile-glued-into-pusher-this-is-not-a-live-round/
Seems like they wouldn't get up to speed???
Does the pusher get launched back in opposite direction when it goes off?

I couldn't get that setup to work.  The zinc pusher plus the lead 14.5 round was just too heavy to arm it.