357 is not going to fare well long term with the current design. Everything should be good to go for 38 special, even using +P loads.
I have a couple of ideas to reinforce the action, but printing the hammer and breech in CF nylon may be all it takes. I will get around to it eventually.
As expected, the optional steel safety plates do not reinforce the action. I have tried them on the 327 with no change in results.
38 special is going well. The armorer is testing it and hasn’t really had any problems. 327 magnum has proven to be a handful. I don’t regret choosing the 327 fed chamber, but likely we will recommend people go with the 32 h&r magnum chamber in stead. 32 h&r still used magnum powders, so you can really utilize the rifle length barrels. It is a very capable round, and the slight shorter chamber will play nicer with 32 long, 32 short, and 32 auto. I really like shooting the 32 longs out of mine more than anything. No problems other than the hotter 327 loads hurting the brass. The gun holds fine but the brass is wrecked with the hotter 327 loads.
So, you seem like you are in the right track.
Use a 1/4" drill bit as a mandrel to hold the beginner shells for sanding.
For intermediate (or any upcoming load that uses small primers) you use a T25 Torx bit as the mandrel. I recommend a new one with crisp edges. You can also use the torx bit after smoothing the cases to ream out the primer pocket to size.
The beginner loads use a 209 primer. The 209 primers protrude out the back of the case because of the incorporated rim/flange. This makes up for the difference in headspace.
The headspace gauge is .2mm thicker than the shells (or beginner rim+209 flange thickness). This build with 43r Ammo is very forgiving with headspace. If you accidently used a beginner shell to headspace, you can just file some off of the breech end of the barrel, and file the extractor groove a little deeper. If you mess up and have too much headspace, you can sand some off of the front of the receiver to make up for it.
The printed ammo guys were doing this exact thing right before I got in on the action. I don’t have the files or process, but they were able to get useable results with printed cartridges. AFAIK, the two working on printed primers are no longer around.
Baby barret is one of my favorite builds I’ve done. I recommend opting for a full size barrel. It’s also one of my most accurate full DIY builds.
CCI standard velocity is subsonic as well.
Barrel length also plays a large role in how quiet a gun can be. My baby barret, m4gery, and sr722 all have barrels longer than 21" and are very tolerable with standard velocity ammo without using a can.
On the other hand, my 22lr builds with 1.5-4" barrels are some of the loudest pistols I’ve fired.
CCI quiet “semi auto” ammo helps a ton too, even with the shorter barrels. Aguilla sniper subsonic is really nice just harder to find and some guns don’t cycle it well.
I see your problem now. If you are only using these for blanks, with primer only, you could probably use a more rigid material such as PETG. Although something such as PA-CF or PLA-CF might do the trick, I would avoid filled materials because they are abrasive. I have had similar thoughts about adding a steel pin for the anvil in other projects, but since I have started using the primer bar, I have had no reliability issues. This won’t work for your situation though. The steel pin will be the way to go. You just have to make Sure that it stays in place so that it doesn’t become a projectile and damage something.
Those 43R variants are just the initial release. There will be many, many more to come. These include precision oriented slugs, shotshell optimized for alternative payloads, signals, and magnum loads.
I also have another 3d printed caliber like 43R (chamberless smoothbore using off the shelf pipe) for small platforms called 33R. Same concept, just 33 caliber instead of 43 caliber. It hasn’t been released yet. It is intended for a harlot based platform, and the smaller shells work just as well. I don’t think you could reliably make ammo much smaller than a straight walled 32 caliber round, you just don’t have enough material around the primer pocket.
Pretty much all of my printed ammo projects are based on Deep style printed ammo. If you want a bit more information, “The 9mm Deep” has great documentation about this ammo type. It has been out for a while and tested by quite a few people.
Cool stuff. I’m sure that a 209 primer alone is sufficient for these.
As far as the anvil goes for the bernand primers go, check out the 43R intermediate rounds. They have a “bar” that the anvil of a boxer primers seats against. As is, the design wouldn’t work with bernand primers, but making the bar a point downwards would probably do the trick.
You need to print the ammo better if you are shearing the rims.
Make sure that you are using a quality pla+, that has been dried. Print hot and very slow. I recommend the bed being at 70C.
You will never shear a rim with the firing pin strike if you print the ammo well with quality material.
Probably the SY22. I’ve never built one, but many have with success. The NULL is supposed to be an improvement over the NAG, but I have yet to try one of those either.
It Is known to be an unfinished model. Although it contains some very intuitive design features, there are too many flaws to be worked out as it is.
I’m not saying that it’s impossible to get one working, but it’s not going to be a fun time, and will require overhauling many of the models.
There are people that print/make the whole gun (including things like rifled barrels). These are generally called “DIY” builds.
There are also builds that use parts from existing platforms, such as macs, AR, Glock, etc.
Many “hybrid” designs exist as well, that might use some gun parts and the rest is home made.
There are also a ton of furniture, accessories, and modifications for existing platforms.
But yeah we print/make pretty much anything you could think of. I personally like builds that I can completely DIY and 3d printed ammo.