5.56 Timeline

Follow up on “Goofing off”

Figured I’d share what happened for anyone interested.

Previously, I tried to see if I could print a 40mm projectile for plinking with.

Printed projectile left, straight off the printer, chalk projectile on the right.

Mind you, this printed projectile is hollow, with only 15% infill. Excluding the perimeter, it is 85% air. The thickness of this shells is about .021ish of weak plastic.

I recorded video of someone else firing a shot.

The round is disintegrating in the bore.

The projectile is minie ball shaped. I think it is failing at the cup like bottom, splitting apart. I may try a flat base to see if that works better.

The infill pattern is rectilinear. Sort of like a honey comb, but triangles instead of hexagons. This leaves vertical open columns all the way from the bottom to the top of the printed projectile. I may switch to a different infill pattern. Perhaps something like gyroid.

Picture of various infill patters from all3dp.com

In any event, I found some of the blue plastic caps (windshields) for reloading 40mm, so I will be able to make some proper chalk reloads with those.

Goofing off

I was going to write up something of value. . . but nah.

I am seeing if I can 3d print a 40mm projectile I could use. Right now it takes me an hour to print 1 projectile. This first one (v1) looks like the bands will engage the rifling ok, but the base is to narrow to stay in the casing.

Version 2 just finished printing as I typed the last sentence.

That looks like it might work.

I’m fairly sure there is nothing else of interest in that photo.

The major, and I mean major, downside to these 3d printed projectiles is that they are super light. About 20 grams. The chalk training round is somewhere over 100 grams. My reloading scale only goes up to 100 grams and I won’t have access to a precision scale that could tell me the real weight until next week.

At best, these projectiles would be 1/5 the weight of the real deal. Most likely, much much less than that. Thus the sights wont work and who knows where these rounds will go. The weight distribution will also not be centered due to the random infill pattern. But they should go “thump” and go down range, so I have 4 printing right now.

I was thinking about throwing some 20 gauge lead round balls in there to get the weight up, but I realized the way I wanted to do it would still leave it too light. I might design v3 to be two parts that screw together, and the fill it with lead shot. Making it smaller & simpler parts I could give it solid infill to perhaps make the weight distribution more consistent.

I dunno. I want to try shooting some of these really light one first and see what they do.

I was looking at an argument about how to zero the M16/M16A1. One group said you set up a target at 25m and adjust your impact to be 2.4 cm below your point of aim. The other group says that you are suppose to set up your target at 25m and set your impact to be your point of aim.

Much disagreement and people quoting manuals.

Well. . . . I might not be a “printer repairman”, but I can read. The M16/M16A1 has TWO apertures. Not one, but TWO. And guess what? You can zero it two different ways. You can use the unmarked aperture at 25m impacting 2.4 cm low, or you can use the L marked aperture and zero at 25m and shoot point of aim point of impact.

That doesn’t sound any fun. Perhaps we should just shoot at 42m using the unmarked aperture. Wouldn’t that be easier?

The left wants a boogaloo more than you do.

The left hates gun owners, the left hates cops. They dream of the day when they could stay at home and watch CNN to see gun owners and cops killing each other in the streets.

Shawn has written up a fair bit of instructional stuff for this site. I’ve also written a few things where I act like I know what I am talking about. Unfortunately I worry that too much good content we have created has been sorta lost to the public in our archives. Hopefully they would show up in a google search. But who knows for each individual article.

When I get around to it, I want to make a “tutorial” or “training” page on LooseRounds.com. There would be a curated list of the instructional stuff we have written up. That way, say if I wrote a post about how to zero a M16A1 sight, it would be listed in some appropriate category on the tutorial page.

Some other time though, I am just goofing off right now.

Oh, and since I prefer freedom units. 25m is sometimes rounded to 1000 inches. 42m would be about 46 yards, or .21 furlongs.

Let me share a failed gun project

I can’t say exactly when I came up with the idea of this, but I recall a couple of things spurring it on.

There was a thread on a gun forum about discrete ways to move firearms to and from the range. One person was talking about packing their firearms in a bucket. They could put the ammo, paper targets, the firearm, and anything else they needed in an innocent looking bucket and head to the range. I thought that was a really cool idea. I also was enthralled with Polish mini-Beryl and the SIG 552 Commando at that time.

Polish Beryl
Polish Beryl
SIG 552 Picture from https://weaponslover.tumblr.com/post/170539763905

I started to really like the idea of a very short barreled 5.56 that had a folding stock. Back when I was doing thing, the side folding options for the AR were pretty rare and or unreliable. And pistols braces were not a thing, so it was not something that could easily be done.

So did I want?

  • A very compact 5.56 weapon system
  • A right side folding stock
  • Ability to mount optics
  • Ability to mount a silencer
  • Right side folding stock

How did I justify it?

Well, first, I wanted it. That was enough justification. As for performance out of a short barrel. All sorts of groups around the world have fielded very short barreled rifles, From the AK74SU, G36C, Mini-Beryl, etc. There are many sub 9 inch barreled 5.56 and similar weapons out there doing serious work. Are they ideal? No, but they do get the job done. I wanted something that could be small, and discretely packed away.

I looked at options. The SIG 552 was nearly unavailable, and if one could be found it was stupidly expensive. In hind sight, had I just sprung for one, I would probably still have it and it would be a cherished part of my collection.

I saw that there were 5.56 AK rifles available. I also saw that we had all sorts of new options for upgrading AKs. Railed top covers, quad rail hand guards, etc.

This AK for example has a right side folding stock, railed top cover, and other cool upgrade.
This Krinkov by Kreb’s Customs was somewhat similar to what I wanted.

I saw people were making aftermarket right side folding stocks. Why a right side stock? Because the right side is the RIGHT side. Only godless commies or euro weenies would make a stock that folds to the left.

Aftermarket right side folding stock on an AK
Aftermarket right side folding stock on an MP5

I look at the option of buying a SIG 556P, going though the SBR process, then installing a Samson quad rail and an ACE side folding stock. But I was hearing a good bit of bad reviews on the SIG 556 line.

After some thought and researched, I looked into options like it being 7.62×39 or 5.45×39. I finally settled that I would use the AK platform. I would, over time, have a Kreb’s quad rail. I’d use a Tango Down front grip, and have a light mounted on the left side. The barrel would be slightly extended and threaded for use for a silencer. I’d have something like SIG diopter sights installed. At this time it was not uncommon to have HK diopters welded to an AK. Down the road, I might add a M16 mag well and use AR mags. I also liked the idea of using a rail mount on the AK rail to add my favorite optic, the ACOG.

What could go wrong?

I picked up an Arsenal SLR106UR rifle.

I decided I’d settle for a left side folding stock, as this style folding stock is pretty great. When open, it is like having a fixed stock.

I went with the rifle, as I read all these people say you could cut down the barrel and it would just work. I wanted to have the barrel cut down a little long, and threaded for mounting a modern western silencer like my Surefire 556K.

I had a local dealer SBR it. When I chopped the barrel it didn’t run right afterwards. I ended up having to send it off to have the gas port worked on.

The Arsenal finish was especially bad. It seemed to come off when I looked at wrong.

I tried a few different front hand guards.


An Ultimak worked, but got very hot fast. It would burn my fingers.

A bought a rarer set of machined delrin hand guards. I was going to run this bottom with the Ultimak top, but I realized it would take massive amounts of fitting to get this to work, so I got rid of them with out ever using them.

Eventually I ended up using the Kreb’s quad rail I planned to get from the beginning.

I had issues with excessive windage preventing zeroing. Reliability was just not there. It looked cool and was fun to play with, but it felt heavy for the size and just not very good.

I tried different different set ups, never got anywhere near the performance I would consider acceptable.

I had even picked up two different AR15 magwells for the AK. Either would have required modifications to the receiver, but had that work been done, I would have been able to switch between using AK mags or M16 mags. Had it been working well, I would have had that modification done.

In the end, I parted out the accessories and sold the gun at a loss. Put a lot of time and effort trying to get an end result with out realizing that what I was starting with was never really going to do what I wanted.

I’m not saying a “Krinkov” style AK is bad, it just wasn’t what I wanted to begin with. It wasn’t as light or compact as I wanted. Mounting a suppressor didn’t work out. Optics mounting never worked out the way I wanted. It just kept slipping father and farther away from my initial goal.

Don’t make the mistake I did. Don’t sick money into a nebulous project with out knowing if you can get the result you want in the end.

I did learn that I like the idea of a 5.56 AK. So the only AK I own is a 5.56 AK.

Anyways, thought I’d share that gun project of mine that didn’t work out. At least I learned from it.

Or maybe not.

still folds to the wrong side

Reloading 40mm Chalk Rounds

Back when I ordered my M203, chalk rounds were about $5 shipped. When I got it, it took me a bit but I managed to buy a crate at $7 shipped. Still it is getting harder and harder to find these rounds. So, like many shooters shooting expensive ammo, I am going to reload.

Image from ldsystems.us

Chalk rounds are pretty simple. A blank, a case, a pusher, a cone, and chalk.

First, I have to punch out the old blank. On some of these cases, the blank came out easily. Others not so much. There is some sort of black sealant uses on these cases that made it kinda tough to get out.

At first I used a brass punch. After that failed, a few minutes on the lathe got me a stainless steel punch. The narrow diameter is about .01 smaller than a quarter inch. I started using a press to punch out the blanks.

Note the black sealant
Black sealant everywhere
Fired blank next to an unfired blank

Maybe I shouldn’t call this a blank. It might technically be an “impulse charge”, but that is semantics. I’ll keep these spent “impulse charges” as they can individually be reloaded. I bought mine from Gunbroker.

The replacement blanks can easily be pressed into the case. I didn’t bother with adding any new sealant for these reloads.

In the middle of reloading
The cones press on to the zinc pushers, the pushers can be pushed by hand into the case.

At the moment I am lacking cones. I am wondering if I 3d print if those would hold up to the firing.

Reloading the chalk rounds is very easy. Getting the components is the hardest part.