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On 300 Aac Blackout

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So, I've been playing with 300 Blackout. I bought an upper at The Big Gun Show in Tulsa a couple years ago. It was $250, brand new, with a bolt carrier. CHEAP. Well, as we will get to, the reason it was CHEAP was because it was CHEAP. Anyway, this is to further my quest for a cheap to shoot center fire rifle.


I dug out all my 30 caliber boolit molds. I had some SKS/AK molds and some other 30 caliber molds, Lee, Senco, etc. I have a set of Lee dies and a Lee case trimmer, the hand crank kind that goes in your press.


Making the brass:

I dug through my "unsorted" brass giant coffee can for 223/556 brass. Using my air high speed muffler cut off tool (HF), I held a piece of brass on my vice and cut the neck off right at the start of the shoulder, or the base, leaving a straight wall case. You run that through a standard sizing die and it will size and make a neck down to 30 caliber. Next, run that through the case trimmer to get it to the "trim to" length. Check with calipers.



This was very tricky. Most all of the bullet molds I had were the wrong shape. To function properly, the bullet needs to be real long, pointy and skinny at the front. The AK mold was in the 126 GR range and if loaded short, it would kinda half-assed work, but still not right. Most of the bullet profiles would slam up against the feed ramps and gouge the bullet so that it wouldn't chamber. About to give up, I bought the Lee 30 cal 230 Gr boat tail mold. I cast some up. They fed great. I ran a pot's worth of lead through the dies and water dropped them. PROBLEM: Water dropping these long bullets made them curve, like a Samurai's sword. Not all of them, but more than half. After culling out the curved ones, I powder coated the good ones. Put them in a plastic coffee can with some black Airsoft BB's and a couple tablespoons of HF red powder coat. Put the lid on and shake the crap out of it. Pull the lid off and pick them out with some needle nose pliers and put them on a cookie sheet covered in Reynolds Non-Stick aluminum foil (what an invention.) Make sure none are touching and turn the oven on to 400 and come back in a half hour or so. Take them out and let cool. Powder coated boolits. I ran them througe my RCBS Lubamatic with no lube, just sizing them to 309.



The lighter bullets did OK with 296, but the heavy 230GR bullets didn't handle the 296 well at all. This is a rather new caliber, so loading data is not like loading for 30-06 or 223. I was working up the 296 load, trying to get a load that would lock the slide back on an empty mag, and when I got there, it was WAY over pressure. Like blow the primers out over pressure. OOPS. I was about to give up and buy an adjustable gas block when I thought I would experiment with other powders that I had in stock. I have some IMR4198 left over from the 70's. It doesn't meter for crap, which is why it is left over from the 70's. I worked up to 11.5GR of IMR4198, and that was actually working pretty well, locking the slide back on the last round and no over pressure signs. Unfortunately, it's total lack of metering and actually breaking my Dillon RL550B powder measure in the early 80's is a major drawback, so I started digging around for something else. I have some H335 left over from the 80's. Yeah, I haven't been reloading much. The 90's was my lost decade. Nothing happened then but school. The OO's was mostly recovering from the 90's. Anyway, I started working up the H335. What I came up with was 13.0GR of H335 and that Lee 230Gr (actually 229Gr as loaded) powder coated bullet. No over pressure signs and it functions great in my upper (carbine length gas tube, I think.)



I load the bullets OAL to 2.24-ish. Max OAL is 2.26, but I had magazine issues with that length. Oh, my test bed magazine is a 20 round Genuine Colt mag.


The Cheap Upper:

So, during all this workup, I started having feeding problems, and not because of the bullet shape. Problems like there's an empty shell half in the chamber and now another jammed up against it. In other words, the extractor wasn't. Took the bolt apart. Everything looked OK to me. No gunk under the extractor. You can see the tooling marks from turning the bolt, like a giant spiral all the way down. So I looked into all this "O-Ring the Extractor" stuff. What the latest thing is, apparently, is to to put a small O-Ring around the extractor spring, then put it all back together again. I dug out my Harbor Freight O-Ring kit. Like 50 different sizes of O-rings. Every time I use one, that thing pays for itself. Second from the smallest fit around the extractor spring perfect. Put it back together and no more extraction problems.


The magazines would not fit right with the upper locked down. Same thing on a different lower. Some DyChem showed that the part of the upper just over the feed lips of the magazine (tried different mags too) was too shallow. Some light Dremmel time and emery cloth and now the mags fit. Like I said, there's a reason the upper was CHEAP. I suspect the only thing Mil Spec about it was the top 1913 rail. Oh well. The muzzle brake looks cool, stainless barrel, free floated forearm.


For a sight, I have cheap red dot. I'll have to admit, these red dots are kinda nice, especially as... a-hem... our eyes ain't what they used to be.


As much trouble as making the brass is, I didn't want to loose it. I have several brass catchers. One is a real nice stiff plastic one, but it doesn't fit on a flat top receiver. Only on an original or A1 style receiver. That wouldn't work. I bought a bag type one years ago. Couldn't find it for anything. Screw it, I bought another Caldwell bag type on amazon. With some bending and tweaking, I got it to stay over the mouth of the ejection port. I think it works OK, and I can keep up with my PITA to make brass.


Now that I had the right bullet, right powder, a mag that worked (plastic one didn't), I was ready to start chucking out some ammo. I dusted off the RL550B. I haven't loaded a bullet on it in probably over ten years. It was still set up for 7.62x39, actually, from way back when I was messing with my Spanish 93 Mauser in that caliber. I was going to order a set of change caliber stuff for the 300 BO, and on looking, the powder drop is the same as 7.62x39, and of course, the base stuff and buttons are the same as 223, so all I really needed was a tool head and powder die. I took the 7.62x39 dies out of the tool head and used that one. AK ammo is so cheap today there is no point in reloading it. Problem: The powder drop funnel would not flare the mouth for the cast bullet. A call to Dillon tech support and what I needed was a 30 Carbine powder drop funnel. I ordered one. Meanwhile, I set up the rest of the Dillon for 300 BO, making sure the bullet seat depth is where I want it and that the Lee Factory Crimp die is not mashing it too much.


With my casting the bullets, I think my per round cost on these is sub 8 cents, or less than the price of a 22LR, if you can find any for sale. It makes a whole lot more BANG than a 22LR for about the same price.

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Here is a spreadsheet of all the loads I could find on 300 BO. There are probably more out there, but that should be plenty to get one started. Uh, guns are dangerous. Reloading is dangerous. There's commies everywhere, we'll all be killed. Start at a reduced load and work up and You're On You're Own. (AMF YOYO).


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Here are some pics.


Here's the $250 upper.



And where I had to do some grinding on it so the gold standard (Colt 20 round) would fit:



Here's a batch of cookies right out of the oven:






Some boolits that didn't work out:



Left to Right, 126Gr Lyman mold for AK, a 168-ish grain Lee mold, a 200 grain Lee mold. Wouldn't feed for crap, although the 126Gr Lyman almost would, but was way too short. That 200 grain Lee boolit is fantastic in a 30-30, by the way.


Loaded round:



Can't beat the progressive Dillon RL550B for chucking out rounds:



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Thanks, Clem. I would like to leave a reference so people can do things like this without scouring the Intr4w3bz, y0 for hours, coming across conflicting data, etc. Some of those failure bullets might work great in a bolt action, if there was one, but they don't feed in an AR. And I was getting the occasional keyhole with them too, shooting at like 25 ft, which was weird but I suspect the very long distance between the seated bullet and the start of the lands in the chamber was the cause of that. They had to be really short (deep in the case) to have some chance of feeding. Just didn't work out.



So here's the cost breakdown:


13gr H335: $22/lb, or $22/7000gr, which comes to about $0.04/13Gr

Primers: $0.03 ea

Lead: Well, I scrounge a lot. I cost that at 0. I still have some I bought at $0.10/lb. 230gr at $0.10/lb is 3 for penny.

Powder coat: https://www.harborfreight.com/16-oz-powder-coat-paint-red-93309.html

One pound is six bucks. That makes a lot of boolits. Not sure how many, but well over a thousand using the shake and bake method. I put a tablespoon in the can every few hundred.

Brass: Leftover/scrounged 223. Free.


Add in some electricity and nonstick tin foil and that's about it for consumables. I'm not going to cost out the case lube. At ten bucks for a huge jar of lanolin, it is probably around a hundred for a penny. So, 4 cents powder, 3 cents primer, MAYBE a penny for the bullet and I'm calling it 8 cents a pop in 2017 dollars if one were to source powder and primer at today's prices. I still have leftovers from a long time ago, so I would say that my unadjusted for inflation cost on these is closer to three cents.

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Doc I really enjoyed this post, thanks a bunch for taking the time to do it! I've played with ARs for years but never given the 300 blackout even a second look till now . With the price of parts still falling and the pile I accumulated the last few years I may just have to start in on one.

I've never cast anything out of lead and have read that wheel weights are really poor stuff but I just bought a couple sinker molds last weekend thinking I'd try to make some sinkers out of the buckets of old wheel weights that have been taking up space in my shop for over 20 years lol... What does your experience with pouring bullets tell you I need to do on my sinker making, any advice would be appreciated. I've got the molds and nearly half a pickup bed full of weights (owned a tire shop years ago) but was wondering about how much heat it and what kind of source I could get by with on the cheap. Would a propane fish cooker ever get them hot enough?


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Hey Jim,

I've been casting bullets for 43 years now. I have always used wheel weights, primarily. First because that's what I could scrounge and buy from gas stations when I was a kid, then because I bought a lot at an auction of a tire shop that burned to the ground. I mix in whatever I can scrounge. A woman at work gave me some lead stained glass window joiner stuff that she didn't have anymore use for. That got mixed in with the wheel weights. Bullets I come across from the tree stump that is my target holder or the gun range, a length of lead pipe, whatever I have gets mixed in. Nothing wrong with wheel weights. Be careful not to use the zinc ones. They say they will mess up your whole pot of lead and you'll have to pitch it. My wheel weight collection comes from before they started using zinc.

I have used a small cast iron pot and a coleman camp stove before. Not my preferred method, but it works. I used one of these for decades:




until it finally gave out on me. I replaced it with this:https://smile.amazon.com/Lyman-Big-Dipper-Casting-Furnace/dp/B0037NA7ZA which I can't say is any better. I think I actually prefer the Lee, although it holds a little less. My casting dipper fits the Lee better.


"On the cheap," you need a small pot, preferably cast iron and not momma's cooking pot, and a heat source. It doesn't take a whole lot of heat, as I mentioned the 1 burner coleman stove worked fine for me for a few years until I could find my old Lee pot again. And something to dip the lead with. Not sure how big your molds are, but the dipper should be bigger than the mold. You might be able to make something out of an old spoon or smaller ladle. Or if your molds are large, something like this to melt a batch in and pour might work:


My dipper is like this: https://smile.amazon.com/RCBS-80015-Lead-Dipper/dp/B000MLAWHS only older.


This is what I used to use on the coleman: https://smile.amazon.com/RCBS-80010-Lead-Pot/dp/B004XZGUSE



If you're not using a dedicated electric lead furnace, be careful not to get it too hot. The Lee and the Lyman have thermostats.

Put your wheel weights in the melter and start the heat. When it is all melted, break off a chunk of candle wax about pea size or 2 pea sized or so. Throw it in the lead. Touch a match to the molten lead to start a fire from the fumes of the melting wax. Stir the lead. All the impurities will float to the top. Skim them off with an old kitchen spoon now dedicated to casting. You're now ready to cast. Take your mold and (optionally) smoke the mold by lighting a match and letting the smoke go in the mold cavity. Put the bottom of the mold in the molten lead to bring it up to temperature. When the lead drops off, it is up to temp. Pour the lead in the mold. Move the mold over to a larger container like a large metal coffee can and knock the sprue off by striking the top plate with your stick (I use an old axe handle piece). You want to knock the sprue into the metal coffee can. Open the mold and hold over a folded in-half towel (not momma's good towel). You might have to strike the mold handle at the hinge to shake the bullets loose out of the mold and onto the towel. Close the mold up, reset the sprue plate and repeat.


If you want to come down to NW Arkansas some time, I'll demonstrate the whole process for you.



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WOW Doc !! What a treasure trove of information! Thank you very much! And thanks for the offer of a demonstration, I'm in your area almost nightly , I just wish it was during the day and I wasn't always racing my log book I would definitely take you up on it. But I think I'm pretty well educated after you rundown. I believe I'll invest in an electric melter and maybe a few handgun cal molds after reading what you've written. What do you do about the steel wheel clip on the weights? Just dip them out after melting ? I'm thinking I might just wire them together where they'd be simple to lift out? Thanks! Jim

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When you put the wax in and it lights off, all the impurities float to the top, including the steel clips. That's part of what you skim off with the old kitchen spoon. No need to wire them together. They'll be on top.

When making bullets, you will probably need a sizing set. I use a RCBS Lubamatic, but the Lee sizers are cheap.

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Here is how I powder coat the bullets. This is on a Lee mould .430" 255gr bullet I cast for 44 mag to use in my Desert Eagle. Note that using cast bullets in a Desert Eagle is supposed to be a big no-no because of the rifling type. However, I have run these through with no problems at all. Well, the only problem I had was that my load was a bit hot and I was getting pressure signs, so I'll have to back that off. Apparently the load data I used was not correct. I think it did say "rifle only," but flat primers are flat primers. So, with a "too hot" load and a cast, powder coated bullet, zero leading in the micro-groove rifling. That's good enough for me.


Here's the Airsoft BB's, coffee can and the HF powder coat:



I put about a half bottle of BB's in the coffee "can" (plastic, actually), and add about 25-30 boolits and periodically add another tablespoon or so of powder coat. I've been using the same set of BB's for, I dunno, maybe 750 bullets already. I don't think you can wear them out.



Then put the lid on and shake the crap out of it. I use a combination of rolling them along the can sideways and back and forth motion. This is after maybe 20 seconds of shaking:


It needs a little more shaking, but not that much. If after lots of shaking, there are still voids, then add a bit more powder. I pick them out of the mix with some needle nose pliers, put them on a cookie sheet lined with the non-stick aluminum foil, put them in the oven, set to 400F and come back in a half hour. Results:



These 44mag boolits will sit on their base pretty easy. Note that even the bases are fully coated when done. The 230gr 30 cal boolits didn't want to stand up very easily, so I just let them lay down. Any powder coating irregularities doesn't seem to matter in the final product.


Here is my casting station:



Left to right: Wax candle for flux, wet sponge to cool overheated mould, can to hold impurities skimmed off the top, Lyman casting furnace, dipper, spoon, coffee can (metal) to catch sprue as you knock it off, coffee can to hold completed bullets once the towel is "full" and I am not water dropping, bucket with cardboard funnel for water dropping, towel to drop bullets on if I'm not water dropping, gloves, axe handle.


Some notes on Lee moulds (molds): As I have said, Lee is like the Harbor Freight of reloading. Some stuff is great, some good, some OK and some a bit iffy. All is a good value for what you pay. Lee moulds are a fraction of the price of other brands and they come with handles. Other brands, you have to buy the handles separately. Lee sells handles for other brand's moulds too, and I've used those. Anyway, the Lee moulds are aluminum. They heat up faster and you can get to casting good bullets sooner with the aluminum moulds. They also can NOT take a beating like a RCBS, Saeco or Lyman mould can. You have to be a lot more careful with them. For example, I'm used to slamming the mould closed and slamming the sprue plate closed with the mallet on a Saeco or Lyman steel mould. With the Lee's, I carefully close the thing with my gloved hand. I had a 7mm Lee mould for my 7x57. There are locating pins in the Lee moulds and a receiver pin to line up the halves. With the 7mm mould I had, the locating pins/receivers were walking out on me and the mould halves weren't joining up properly. I had to pitch (recycle) most of an entire batch of funny looking boolits. I would tap the pins back into location and they would almost immediately walk out again when I started casting. I contacted Lee and their tech support people told me to peen the pin things and offered to do it if I wasn't comfortable peening them myself. I peened them on the 7mm mould and they still walked out. I think after walking out a few times, the holes were now oversized. I returned the mould to Lee and they sent me another for free under their 1 year (I think) warranty. I peened the pins on that one and have had no problems with it. Oh, shipping on sending the thing back to Lee was probably 75% of the cost of a new one on Amazon, but warranty is warranty and 75% of the price is better than 100%.


Now, whenever I get a new Lee mould, I peen the pins/receiver pins on it and that, combined with being much more careful with the mould, has been working out for me. Here's the 44 mag mould peened:




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I'm getting a bit off the 300 BO subject, wandering into reloading in general.


I was loading up the 44MAG bullets pictured above in my Dillon RL550B. I'm using Lee dies, labeled "44 Special - Also reloads 44 Magnum" or something like that. I actually kinda like the Lee decapping system. I don't know how many RCBS decapping pins I've busted over the last 4+ decades. They should sell them by the dozen, at least. With the Lee dies, all you'll do is push the decapper out the top, stop and reset/torque it down and go on.

I put a fairly decent bell on the mouth of the 44mag cases so the lead bullet won't shave off. When the case went up into the bullet seating die, if the bell was on the large size, it was blocked pretty hard at the mouth of the die. A good hard push on the lever would force it up into the die by shrinking the mouth in some, but it was difficult. 3 other things are going on at the same time, remember. Anyway, looking at the die, the mouth had about a 45 degree bevel on it. I figgered that if the bevel tapered in more, that would make it easier for the oversize bell mouth to transition into the die. So I chucked the die up in my lathe, turned it on and took the Dremel tool with a small stone in it and ground the transition zone to a much more gradual angle, then polished it with some emery cloth. I put it back in the press and reset it. No more problems with that die. Worked fantastic in Dillon, even when a case mouth got way too big.

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Back on the 300BO. I have to admit that I kinda like this caliber, especially because I can make ammo in the 8 cent range, not counting brass. Oh, on brass, I bought 1K for 11 cents each from rockybrass.com off of gun broker.


I built a pistol. Anderson lower purchased from the nearest coffee shop to work. No, really, the coffee shop a mile from work sells guns. This is Arkansas. The barrel I used is (was) a 10.5" stainless steel Stoner from Midway. Folding buffer tube. Blade arm brace. UTG 7.5" forearm (from the coffee shop.)


Running it with my powder coated cast boolits, I had a few issues with feeding, usually the first round off the mag, regardless of position. It wouldn't go fully into battery. Close examination of the bullet after ejecting it showed that the bullet was getting scratched up in the feeding process. I suspect that the barrel extension feed ramps were not fully optimized for 300BO. I had the same problem with the super cheap carbine upper I bought. I took a small stone in a Dremmel brand moto-tool and lightly touched the end of the feed ramps, rounding off the sharp edge closest to the chamber. That seems to have helped a lot. I think that the barrel extensions are probably the same as used in 556 barrels, and they probably work fine with the tougher jacketed bullets, but with the cast boolits, they were getting gouged up some, just enough to cause distortion and difficulty in the chamber.


10.5" was still fairly long, especially with a flash suppressor on the end. Too long. I experimented with shooting at night with and without the flash suppressor, and while it reduced the muzzle flash from about softball size to about golf ball size, running without is not blinding like the 223 14" contender barrel, which is more beach ball size. So a shorter barrel with no flash suppressor is not that bad. I would rather have the extra inch of barrel than a flash suppressor, in other words.


I pulled the barrel, chucked it up in the lathe and cut if off to just past the flashlight and Romeo 5 sight (mounted at the end of the rails.) Crowned it with a carriage bolt and automotive valve grinding compound. Put it back together with the now just sub 7" barrel. Gas problems. It has an adjustable gas block, but even fully open, it wouldn't lock the slide back. I upped the charge on the load to 13.7Gr H335 and it almost worked. Back apart again. Teh Intr4w3bz, y0, said that 300 BO gas port barrels from people's observations, run in the 0.076" to 0.120" diameters from the barrel makers. I think I found one reference even to 0.140". This one measured (by drill bit method) 0.100", maybe 0.101". Over on the drill press, I drilled it out to 0.120". Back together again and it works great now.

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