Sizing 312 to 309

[WFO2]

I have a couple of bullets that are going to cast at .311 and .312 . I was wondering if sizing them down to .309 is to much on one step . I plan on using an inverted Lee c press and Lee sizing dies .I will be powder coating after sizing and then sizing again .

[NavyVet1959]

I bought the Lee C312-155-2R (https://www.midwayusa.com/product/752956/lee-2-cavity-bullet-mold-c312-155-2r-762x39mm-312-diameter-155-grain-2-ogive-radius-gas-check) mold last year and have used it for my Type 99 (7.7x58) Arisaka and resized for a .300 AAC. I've only resized one batch so far and it's been awhile, but I seem to remember doing it in one step.

Next time I cast some more of them, I'll try it again to verify...

[MT Chambers]

It will be more of a problem if they are cast hard or quenched.

[Phantom30]

Been there done that. If you have a long drive band on the boolit design, good luck. I start with Lee .314 to make sure they are round or you can mic them out, then press with the .311, This usually requires case lube, then the .309, finally the .308, So why 308, well a HiTek coating is going to add back about .001 to the diameter but ESPC could add .002 to the radius and depending on the chamber requirements you may need to be able to size back to .3085 for 300 BLK or you might be ok at .311 for an AK. I decided to cast smaller diameter PB and just size the ESPC boolit from there, much less work, much nicer product. But you have to have a casting die that throws smaller pre-coated diameter boolits. PS don't forget to clean the sizing lube off and dry the boolits before PC

[WFO2]

Yes looking at 300 blkout .I have three molds coming to try . The Lee TL309-230-5R , Lee C312-155-2R , and the NOE 311-230-FN . I know that the C312 can be used for other 30 cal if it does not work . I'm wanting to powder coat these as I want to run them subsonic and suppressed .I plan on using them PB powder coated .

[Dan Cash]

If you use a good push through type sizer or other nose first setup, you will have good results. Base first sizing can cause crooked bullets and/or swelled noses.

[Dragonheart]

You can nose first size it in one step, but I don't think .003" will be easy on a Lee Press.

[Phantom30]

Well, look up the "Powder Coating 300 BLK BTHP Boolits" thread on page two of coatings and alternatives. The last entries shows the 215gr Accurse Mold 31-215G mold design converted to HP, along with the analysis for mating with the 300 BLK chamber. I am casting this .306 drive band mold this week, ESPC, and should confirm next week that they fire without jamming. They are loaded for 1600 fps and 1100 fps from both 16 and 10.5 inch barrels. HP boolits ESPC very well on an inverse HP spike board.

[WFO2]

Dam interesting Phantom . Wish I had that data before I ordered 3 molds .So what I get form reading the thread you mention you have about got it worked out . Two questions . One can any of the mold I listed be modified to work . Two if a group by happens by Erik let me know . Sounds like the **** for a 10.5 with a can for hogs at my ranch .

[popper]

You can go a little heavy with tin and get them to be smaller. Mould/alloy temp also changes dia. a tad. Problem with sizing down in one step is the pusher plug may leave tails on the PB. I size down in steps, then PC so I can check the PC thickness. If you use lube to size, clean it off before PC - it won't stick to lube. You could get some of the high temp exhaust paint to coat the mould, I haven't tried it - pretty pricey. Just sized some PB for the 30/30 with the Lee setup, 313 to 311, no problem and these are almost all drive band. PCd they come out 313 again, size to 311, no problem. You can use sizing lube after PC.

[Phantom30]

WFO2, Popper is right alloy makes a difference, I have gone from 3% to 6% SN and not only are they smoother and harder but the drive band OD is slightly smaller when it cools. As for Erik@hollowpointmold.com you need to have a mold with enough room at the bottom for the conversion. The Lee TL 309-230-5R does not. Got three of those suckers. The accurate mold 2 Cavity XXL in AL has enough room but the boolit must be less than 1.3xx" long, ask Erik. The largest I have had converted was the 31-240A length 1.33". The largest Accurate makes is 1.375" in length. I am taking the reduced Drive Band 31-240A HP and 31-215G HP to the range Tuesday. Have uncovered a few interesting things about PC not reported as I can tell yet. Will add to that thread when finished next week.

[Loudy13]

Well I tried nose first sizing to .309 the other day with 150gr NOE bullet and I had added a gator check after powder coating (Just trying different options). I ended up having to punch that bullet out with hammer. My fault it didn't have lube and it wasn't gonna go through that way. The bullets that were coated with a Gas check went right through nice and easy. Lesson learned again

[WFO2]

Thanks all I will probably size down in steps .

[Tackleberry41]

I bought the NOE set up, and go in steps on something like that. Have even managed to size already PC coated .314 rds down to .309 without messing up the coating, just do it .001 at a time.

You will probably be way happier with that NOE mold than the Lee 230gr. I was given some of the lee somebody had cast, few were close to 308 much less 309, and then was only one band the rest were undersized. Had to Leement both my 150 and 170gr Lee molds. Still do not shoot very well. The NOE .311-230gr works in my mosins and 308 rifles.