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Lee 155gr 312 cast boolit in 300blk, un-sized?


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I've found that is more like 162 grain as cast. Lee's mold descriptions are often way off from what they actually do. As it happens, I prefer that weight, but you should keep it in mind when using load data, and actually weigh what you are making.

 

I get ~2 MOA with those out of 30-06 and 308 when I keep the pressure/  alloy hardness ratio proper. I've tried them both poly jacketed and using 45/45/10. No leading either way, but I much prefer poly jacket.

 

As for sizing, if it always chambers, fully goes into battery, and extracts by hand, let the barrel be the sizer. If not, there is no harm in sizing. I suggest doing so after poly coating. Lee push sizers are good, and efficient to use. (see the end of this video V) However, I always verify a new sizer. I've found several of mine sized too much. Rather than send them back, I made a hone with a rod and oiled 2k grit sand paper in a drill. I honed them to a high polish and perfect spec to get perfect bullets.

 

Try this :

 

 

Also, what is your alloy, and the book pressure for your load data? to get accuracy, your BHN needs to come out to a deformation level 10% under peak pressure.

 

Here's a cheap way to check your hardness.

 

 

I eventually got a Lee hardness tester, and I think that is a very worthwhile investment if you are going to try to cast for rifle much. As is Lee's 2nd Edition, since it gives you more accurate scientific explanation, formulae and charts for the relationship between hardness and velocity. (Spoiler-it's pressure not velocity. Lyman isn't willing to own they were wrong about this, and keep publishing "information" that sometimes works and sometimes doesn't for this reason.)


45/45/10 is an easy, and cheap lube process- basically tumble lubing with a better lube. Recluse derived it as a combination of heated Johnson's past wax and lee liquid alox, with a bit of mineral spirits to replace the solvents which evaporate off of the JPW. It dries hard, faster, smokes less (~ none if you keep it light, which you should) and dries faster. Way better than pure alox. It is also capable of working to higher velocities than pure liquid alox. (Lube failure is related to velocity)

 

These guys now make it ready to go, so I'd do that if that's what you want. http://lsstuff.com/store/index.php?main_page=product_info&products_id=31

 

I still prefer the poly coat, but this is the next best thing IMO.


p.s. both rifles were 1/10 twist IIRC.


I harden my bullets by bringing them up to 400 for about 45 minutes then dumping them all in cool water at once. Then they are more uniform, and usually about 6+ Bhn higher than air cooled. 2-4 BHN higher than dropped into water from the mold, and more consistent.

Edited by GunFun
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Why not take one of your as cast bullets and simply slug the bore with it?  Start it point first into the muzzle, then with a precision rod PUSH IT DOWN and through to the chamber.  Remove and eyeball the depth and amount of the rifling.  The amount of pressure required to push the bullet down the bore will tell you if the bullet is too big in diameter or not. 

 

The amount of resistance that is OK and what is excessive is a learned thing.  Do you or have you done any muzzle loading with tightly patched bullets?  Kentucky rifle type stuff.  Not .68 Minie' balls.  Lots of times, like already said, your cast bullet diameter may NOT be what it says on the mould.  Lots of variables.  Have fun and good luck.  HB of CJ (old coot)

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The general rule of thumb is that ideal is .001-.002" over groove diameter (slugged). This is often not possible with bottle neck cartridges. However, so long as the bullet is not so wide that it stretches the case neck too much to fully chamber with the correct headspace, any lead alloy bullet is safe. I saw someone's data a long time ago. The difference in pressures from way oversize lead to properly oversized lead is negligible. Both were still far less back pressure than a solid copper bullet of the same weight takes to start. So the upshot is that if it fits, it is safe.

 

In theory, it is also more accurate to let the barrel do the sizing rather than a die which may have less perfect concentricity. As a counterpoint to this theory,consistent sizing greatly affects the level of neck tension, which has been frequently shown to have a substantial difference on velocity. Most rifles don't give you much room to play with. For the rifles I tried, I think the ideal size would be .3085". .309" works good, but the occasional bit of springback after sizing will get you a .3095" bullet. These will usually feed and headspace, but if you try to unload the gun you will find that great force- rubber mallet force may be required to extract the round. Your gun may vary from this. I don't know how picky .300 BO is, but it headspaces off of the shoulder rather than the case mouth. That should make it more forgiving with fat bullets than some other cartridges. What some will do when you have an oversized bullet is swage it with the crimp on the case neck, so you basically get a healed bullet like a .22LR The displaced lead flows just in front of the case mouth and may make a little ridged ring which interferes with feeding. This issue is what got me to just sized all the 0.312"/".308 nominal" bullets to 0.309" actual. (including coatings). As I said, I am tempted to get a .308" die and hone it up to 0.3085" which should make it work well in just about everything.

 

With the volume of rifle shooting I do, I don't mind taking an extra 10 minutes to size every 700 or so bullets in front of a youtube video. If I do them while still kinda warm from the coating, they just glide through. 

Edited by GunFun
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Oh ya will do, just trying to break midways min order for moolah off...

 

That powder coating process seems craaaaaaazy

Oh and I've kinda hardness tested my lead before. Can't remember what it was but real close to lyman 2, or the ideal hardness for most stuff

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Lyman #2 Air cooled is ~12 BHN, hardened =14-16 BHN. That makes it suitable for 9mm to .357 pressure levels, but only reduced power rifle loads. It is basically a pistol pressure alloy,  a lot of people think cast is only good for pistols, because they never match their alloy to their pressure.

 

For full power rifle data, you are probably going to want to add some "superhard" from rotometals and then harden the bullets, to get them above 25 BHN or so.

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ah, good call. ya hadnt thought about pushing em fast. didnt wanna get into gas checks etc....takes me so long to make a few boolits anyways didnt wanna lengthen the process


realy depends on what this gun cycles. if its supers only, then its whole new game...

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I was thinking, (dangerous for me) that since you are running right at or below the speed of sound for use with a can, you can use a good proven lead mix that will perform at that velocity without leading, then you are good to go.  Have fun.  HB

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ah, good call. ya hadnt thought about pushing em fast. didnt wanna get into gas checks etc....takes me so long to make a few boolits anyways didnt wanna lengthen the process

realy depends on what this gun cycles. if its supers only, then its whole new game...

 

Polycoating makes gas checks obsolete.... You just need to have the right alloy, and do some math.

Also, we can speed up your bullet making process a lot with some best practices.

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It takes me a few minutes to set up and put away. Once I am actually casting, with that mold I get 3-400 good bullets cast per hour. I will usually cast for 3-4 hours at a stretch, then spend another 10 minutes of work to harden the entire batch. That involves putting them in a toaster oven at 400 *f for 45 minutes, then chucking them in a bucket of cold tap water.(~5 mins of work) Then I dry them in the same toaster at low temp ~100 F for an hour or so. (~5 mins of work). Here' I'll run my hands over them and pick out anything that feels "off." Then I chuck them in the tumbler with powder coat for a half hour & sift them onto the baking rack. (~5 mins of work) Back in the toaster oven for 10 minutes, and ready to serve.

 

Since those are rifle bullets, and are likely to go into picky rifles, I take an extra 10 minutes to run them all through the sizer. This goes fast. There is almost no resistance, and I sit there with a hand full at a time watching something on netflix and stuffing them through the sizer as fast as I can. It doesn't even require a full press stroke and my hands can stay right at the work. I push the press handle with just light finger pressure and it barely stops moving at all. Even though few need the sizing, it guarantees they are all the same and I won't be fighting 1 in 12 or so bullets being hard to chamber/extract. It also saves shaving on seating for the occasional slightly fat bullet. The other thing I like to do at this phase is keep my sizer press set at about eye level with a light nearby. Even if I am watching TV, it makes it easy to catch the few defects I missed earlier. If something has flaws, you will feel it going through the sizer and can cull it out easily.


I also like to wait a day or two before actually loading them. Age hardening can get you an extra BHN or two, and that helps keep them from getting dinged up by the tooling. The whole process takes a little time if you count waiting on stuff to do its thing, but you aren't actually there working. i.e. it can dry overnight without you there, tumble without you there.... So you can watch a video, or go to your reloading press and reload some other ammo while stuff is tumbling or baking or whatever. 

Edited by GunFun
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I was thinking, (dangerous for me) that since you are running right at or below the speed of sound for use with a can, you can use a good proven lead mix that will perform at that velocity without leading, then you are good to go.  Have fun.  HB

 

A friend (dolomite supafly here) helped me a lot with this stuff. He thought the same way and was using a DI AR with a can and 300 BO. The gas port was basically picking up vaporized lead and giving him a lead mustache with the backpressure from the can. That direct impingement tube vents to the action/ out the charging handle area on an AR. No bueno.

 

This is why we both took up with the polycoat. The bullet is fully encapsulated and no lead vapor can be made. My general intent is to do an SBR piston AR for the eventual can, but I would feel OK with using a DI gun and powder coated ammo. Same for the 300 BO tavor I hope to have some day. When you  pick up recovered bullets, you can see that the rifling doesn't usually even break through the polymer. Really the lead is more sealed off than an open base FMJ. Even smashing them flat as a nickel with a big hammer on an anvil, the coating is intact. Impressive stuff.

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GunFun;   Thank you.  Right now the ongoing off and on project is a SBR M2 Carbine using a not yet purchased Elite Iron can.  Others have shared so-so expectations with gas coming back through the chamber into ones face using a USGI M1 Carbine with a suppressor.  Worserer with a short 14.5 inch barrel.

 

Back in high school before the dawn of time or around 1965, we shot 115 grain Lyman round nose lead cast bullets through USGI M1 Carbines within the High School Rifle Club.  Only my early spring tube Rockola shaved lead, then only at that pesky .070 gas port hole leading into the gas block and piston.

 

The cure then was to take a drill bit and a brace and bit and hand ream out the gas port.  Easy and quick.  Now over 50 years later I am beginning to better understand why my Rockola shaved lead.  The velocity was around 1975 using 15.0 grains of H110.  Sounds like your cast lead bullet prep receipt works.

 

HB  All US Code Laws And NFA Rules Apply

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Good thinking. Angling the port eliminates the actual shaving, but gas cutting is the real thing to watch out for. The corner of the base that passes that port makes a high pressure vent of hot gas, just like a cutting torch. That makes vaporized lead. Jacketing that extends to the corner is enough to eliminate this, as will a gas check, or poly coat, or the old fashioned paper patch. It really doesn't take much, but there needs to be something. 

 

The neat thing about the poly coat is that when you remelt recovered bullets or culled rejects the poly jacket will hold its shape and float on top of the pot. A little bump and it will dump out all the molten lead. So what that means is that it can handle a fair amount of heat higher than the lead before it fails. It takes 400*f to polymerize, but will stay intact on top of 750*f melted lead- at least for a good while.

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GunFun; thank you again.  I believe I will share your experiences with the guys at the various M1 Carbine forums who are still having leading problems using cheap home cast bullets with no gas checks.  Now we will know why.  HB

 

The little rifle M1-M2 Carbine needs a full power load to function properly.  Especially the M2.  This means around 15.0 grains of H110.  Velocity is or should be around 1975-2000 fps.  Is this too fast for a cast lead bullet?  Thanks again.

 

All US code Laws And NFA Rules Apply.

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GunFun; thank you again.  I believe I will share your experiences with the guys at the various M1 Carbine forums who are still having leading problems using cheap home cast bullets with no gas checks.  Now we will know why.  HB

 

The little rifle M1-M2 Carbine needs a full power load to function properly.  Especially the M2.  This means around 15.0 grains of H110.  Velocity is or should be around 1975-2000 fps.  Is this too fast for a cast lead bullet?  Thanks again.

 

All US code Laws And NFA Rules Apply.

 

Don't think "too fast" think "too high pressure"  and not for "A cast bullet" but rather "a cast bullet of 12 BHN" vs "a cast bullet of 24 BHN...."

 

So the answer to that question is based on what cast bullet they are dealing with. 

 

 

This is why "modern reloading 2nd Edition" by Richard Lee is so much more useful than the Lyman reloading books, including their cast bullet manual.

 

If you have that book, Chapter 7 and 8 are invaluable. A lot of the load data has a multiplier that can be used to estimate pressure and velocity at levels under the max load of a charge. So if the max charge is 26 grains of X powder, you can figure out your velocity and pressure at 23 grains. Or you can figure out how many grains to reduce to get a certain pressure. It will get you very close, so the trial and error is cut way down.

 

So you can work back toward your starting load and have a pretty good idea what the pressure will be. Then you only need to vary your load by .1 grain increments for a grain either way of that charge to find the sweet spot for your alloy. 

 

Or alternatively, in your situation, you know what your charge is and don't want to change that much. Therefore, if you set the charge constant and bullet weight constant, you know the pressure. This means the variable you change is hardness, and the formulas can be used to work out the projected optimum. Then tweak the alloy a little or the charge by a half grain either way and you should find an accuracy node.

 

If you give me your bullet weight, I will try and do the math. Make sure it is the actual bullet weight, not just what the mold claims to cast. Sadly the book does not have the 1 grain factors for 30 carbine, like it does for 308. However we can still get close. It could be that you can get similar velocity with a powder which has lower peak pressure too, which will allow you to get away with a softer alloy. i.e. "Hodgedon Little gun"

 

Example - without reduced charge multipliers, but since we are at max, we don't need them to determine nominal  p.s.i.

From Lee 2nd ed at pp350

Lee's data for a 30 Carbine 110 grain lead bullet is 15.0 grn max of H110 for ~2106 FPS @ 3650 PSI

 

We want a bullet that has an ultimate compressive strength of 3650 PSI to 110%*3650   (4105PSI)

 

The chart for pressure on pp 107 (which also comes with their harness tester) says that the closest BHN range for these pressures is 28.5 BHN --33 BHN. 

 

Lyman #2 alloy (~Air cooled wheel weights) Just won't do that. You will need to add tin and antimony to your alloy and harden it like I described above to get good performing bullets at that pressure. You can use this: http://www.rotometals.com/product-p/30_antimony_70_lead.htm There are alloy calculators out there, but I would bet you could just email the guys at rotometals and ask them how much to add to get what you want.

 

If you want good accuracy from your current alloy, the first step is to bake it and quench it, which will get you 14-16 BHN, instead of the 12 or so air cooling gets you. This will give you good accuracy from load data that has max pressure of 20433--21196 PSI.

 

Remember how I said the data showed Hodgedon littlegun listed for the lowest PSI at max load for similar velocity? Maybe your Lyman, hornady, speer, etc. books will give different powder options for lower pressures and high velocities. It's worth a look.

 

Let's see how that plays out

 

From Lee 2nd ed at pp350

Lee's data for a 30 Carbine 110 grain lead bullet is 15.0 grn {compressed charge} max of H LIl Gun for ~2064 FPS @ 29800 PSI, a lot lower pressure for about the same velocity. This is where Lyman screws you up, by talking about velocity. Velocity tends to go up with pressure, but it doesn't always go at the same rates. 

 

So a bullet that sucks at 2000 FPS with one powder might do great at that velocity with another. people who talk about whether a cast bullet can handle a certain velocity might have a lot of experience, but they have been blundering around in the dark looking at the wrong factor. Their information only applies to their particular recipe with their particular alloy, and odds are they don't really know what they are talking about. I don't want to sound arrogant, many of them are smart people, but so were doctors before microbes were discovered and understood.

 

Back to the pressure table on pp 107: For a max PSI of 29800, the alloy we want is going to be between 22.7 and 23.8 BHN. That's quenched LinoType levels of hardness. i.e. A dramatically cheaper alloy and easier to work with, and not all that rare to find. Just be sure to check that your scrap LinoType lead has not been diluted by the print shop. It often is. 

 

So about 15 minutes of looking at the book and comparing data found something that is probably going to work pretty well with very common alloy in a fairly common powder. The accuracy would have sucked using a max charge of H110 and Soft lead bullets.

Edited by GunFun
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Thank you again.  Fifty years is a long time.  We were using wheel weight lead with no gas checks, as the gas checks were considered too expensive.  I think they were either .310 or .311.  And ... only my Rockola shaved or plugged up the port?  None of the other guys ever said different.  Now wondering if they also had leading problems.  .070 drill bits were common.  Long ago and far away.   Also the book back then said about 1975 to 2000 fps and that a max load was necessary for the brass to seal the M1 Carbine chamber and allow proper function.  Lyman 1965 or earlier edition.  This was/is the military load equivalent.  HB

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Right.

 

Lyman was looking at trends and attributed accuracy and leading to a function of velocity. Accuracy is really a function of bullet shape, twist rate, and the ratio of pressure to bullet compressive strength.

 

The factors that affect leading, in order are 1) Sizing (gas cutting leads way faster than a complete lack of lube)2)Lube/Jacket (also hardness acts as a jacket sorta) 3) Hardness / pressure ratio 4) temp.

 

Lube failure is related to velocity,as well as barrel length.  and Lyman still acts as though lube has not improved since 1965. It has. But it was also known false when Lyman was publishing back in 1965. In the 1890s target shooters were getting accuracy anyone would be proud of today using smokeless powder and paper patched (paper half jacketed) cast lead bullets. The paper survived the heat, and also more or less prevented lead fouling. It had other problems though.

 

 Lee published a series of tests which soundly prove that innacuracy comes from either bullets being so hard that they do not obturate to engage the rifling, or bullets so soft that they become deformed by the pressure. By matching the pressure to the hardness, the same bullet type could perform at effectively any velocity you could push it to. There is a limit at which even copper jacketed bullets will explode from the RPMs generated at high velocity, but 30 cal lead bullets were working well over 3000 FPS. These tests were published in the 1980s, but Lyman had hung its hat on the notion that velocity was everything.

 

Therefore Lyman has been ignoring better understanding because it was discovered by a competitor, and spreads information now shown to be partly false.This does the shooting community a huge disservice. Even their current cast lead handbook fails to account for the relevance of pressure to accuracy.

 

Both Lee and Lyman are in the business of selling lube and sizing systems that are based around outdated lube formulas. Most of those will fail around 2000 FPS.

 

Tumble lubing very lightly with 45/45/10 allowed me to shoot about 300 rounds of lead through a 30/06 with no apparent smoke, and no leading. Sure there was powder fouling, but it all came out with a patch. About half of that was loaded up to max charges for jacketed bullets of the same weight. Those bullets did not lead, but they grouped badly because their pressure was too high for the alloy I had. They were about 22 BHN. When I reduced the charge to levels  that would produce about 2600 FPS, they started shooting ~2 MOA. I now prefer to powder coat most everything, but I was having good results even before that.

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On a whim I decided to lookup the pressures for ~150 grain bullets in 300BO and try to work out the native alloy levels using some alloy calculators.

 

post-17871-0-69196700-1432588208_thumb.jpg

 

Looks like we need projectiles calibrated for something in the neighborhood of 46,000 PSI to match full power jacketed bullets...

 

So I plugged an alloy of pure lead + superhard in and increased the percentage until the nominal alloy got up to snuff.

 

post-17871-0-71243800-1432588181_thumb.jpg

 

So it looks like half  pure lead by weight at around 30 cents a pound + half super hard is in that range. However, this calculator is not perfect and is known to give wonky results outside a range of values. I forget exactly what those were. Also it outputs data for air cooled. If this were quenched as I talked about above, it would probably be 4-6 BHN harder, but possibly more. 

 

Based on these napkin type calculations, cloning jacketed bullets for jacketed performance with the powders above would end up costing ~20 cents a projectile. i.e. what you can buy match bullets for. 

 

However, I bet powder selection could bring those pressures way down. I'd be looking at what powder gives low pressures in 7.62X39 since the cartridge is so similar. Also with the long OAL you have loaded to, you are probably going to have lower actual pressures (and less consistency due to airspace) than the data states.

 

 

Some more projections for air cooled hardness:

 

post-17871-0-87157300-1432589562_thumb.jpg

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Unfortunately all of my books were published just before 300 BO became a hit, so they lack any data for that cartridge. 

 

Nosler gives a spread of velocity, but they don't seem to have pressure data: http://www.nosler.com/nosler-load-data/300-aac-blackout/

 

Sierra lets you download their data, which is nice since IIRC they are the same company as speer/CCI, which also sells books

https://sierrabullets.files.wordpress.com/2013/07/300-aac-blackout.pdf

 

They have data for 155 grain and 160, 165,168  grain match bullets, which is helpful since your bullets probably weigh ~160. No pressure data though.

Edited by GunFun
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The other thing I wondered is that your title describes Lee's AK round, and your description talks about the lee/midway 230 grain bullet mold. 

 

The picture looks more like the 230, I think, and those can run well at 1120 FPS just barely subsonic, using something like 5 grains of bullseye or AA #5, etc. -- Don't use that without looking up the data.  This is going to be basically pistol pressure and should work with pistol alloy just fine.

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ya, i am running 230s, cause they easy, but i would rather sling a hundred less grains and stay sub... possible?

im not set up for powder coating yet, seen the 223 lee bator mold? seens that would be a match made in heaven?

 

Bator is tricky to get working right. .223 works balistically because of very high velocity, and bullets capable of those pressures are hard to make for less than it costs to buy.

 

The 160 (really ~155) 312 2r TL mold lee sells should be a good fit though. As a subsonic, it would be on the edge of what you could get to cycle the action, but it might do. And you would be talking about pressures that pistol quality alloy would do fine with. If you have an adjustible gas block you are golden for this stuff, but on your AK, you might need a light recoil spring to make it work well. Just rememeber to put the proper spring back in for full power ammo.

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