Mold for 300blk

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  • Melnic

    Ultimate Member
    MDS Supporter
    Dec 27, 2012
    15,282
    HoCo
    OK,
    My 309 Lee 160grn mold seems to be no good for 300 blk
    https://leeprecision.com/mold-dc-c309-160-r.html

    Maybe its the HiTek coating is not tough enough or maybe the bullet seating but it gets gouged when I load a round in my 300BLK.

    I'm going to try traditional powder coating but I"m also looking to get a mold a better mold more suitable for 300blk.

    What are you guys using and what kind of smokeless powder?
    It would be nice if I could do subsonic with it.
     

    Postell

    Banned
    BANNED!!!
    Nov 5, 2018
    291
    I'm not a Lee person but getting a Lee Expander/flaring die will flair the end of the neck and make seating cast bullets /oversize bullets easier.
     

    Melnic

    Ultimate Member
    MDS Supporter
    Dec 27, 2012
    15,282
    HoCo
    Just to be clear
    Problem is when charging the chamber of the rifle with a round
    I was testing loading an unprimed and uncharged round into the AR
    These had gas checks and no problems seating the bullet

    When I googled around saw no one using this mold in 300blk


    Sent from my iPhone using Tapatalk
     

    Postell

    Banned
    BANNED!!!
    Nov 5, 2018
    291
    Lees 230 grain boat tail was designed for 300 blackout.
    Are they chamber marks or land & groove marks?
    I would change to the 230's if I was to go subsonic.. Lots of load data out on the web.


    Personally I would shoot what you have and see how well they shoot.
     

    Melnic

    Ultimate Member
    MDS Supporter
    Dec 27, 2012
    15,282
    HoCo
    I was eyeballing the Lee 230gr mold.
    I’d like to mold up a bunch of what ever I end up with while sheltered in place as I don’t think I’ll have a chance to shoot for a while.


    Sent from my iPhone using Tapatalk
     

    outrider58

    Eats Bacon Raw
    MDS Supporter
    Jul 29, 2014
    49,818
    OK,
    My 309 Lee 160grn mold seems to be no good for 300 blk
    https://leeprecision.com/mold-dc-c309-160-r.html

    Maybe its the HiTek coating is not tough enough or maybe the bullet seating but it gets gouged when I load a round in my 300BLK.

    I'm going to try traditional powder coating but I"m also looking to get a mold a better mold more suitable for 300blk.

    What are you guys using and what kind of smokeless powder?
    It would be nice if I could do subsonic with it.

    Kinda light for subsonic. I wouldn't go lower than 180gr and I'm a big fan of 200+ grain projectiles. I load all my 300blk subs with Accurate 1680. I've tried all the others and this has been a solid, consistent performer throughout. I use hotter primers as well. Rem. 7.5 BR

    It gets gouged when loading a cartridge or loading into your gun? As Postell suggested, you need to flare the cases when loading lead pills, no matter the coating.
     

    John from MD

    American Patriot
    MDS Supporter
    May 12, 2005
    22,734
    Socialist State of Maryland
    OK,
    My 309 Lee 160grn mold seems to be no good for 300 blk
    https://leeprecision.com/mold-dc-c309-160-r.html

    Maybe its the HiTek coating is not tough enough or maybe the bullet seating but it gets gouged when I load a round in my 300BLK.

    I'm going to try traditional powder coating but I"m also looking to get a mold a better mold more suitable for 300blk.

    What are you guys using and what kind of smokeless powder?
    It would be nice if I could do subsonic with it.

    I have shot thousands of that bullet both with traditional lube and PC. It's a great bullet for the 300 BO. I am using 17.0 grains of H110 and my barrel twist is 1 in 8.

    For subsonic, most folks use the 230 bullets and a 1 in 7 twist.
     
    Last edited:

    Melnic

    Ultimate Member
    MDS Supporter
    Dec 27, 2012
    15,282
    HoCo
    John
    What OAL did you use?
    I do have enough H110 to make up a test batch to shoot and up to 120 rounds


    Outrider, per post #4 when loading chamber of the rifle
    See pic below (exposed lead on left side).

    Lead hardness is about 10-12


    I think I have a die I can use to add a flair for seating easier

    b7b77ee1122a73cfc0b2f83fd37cc0e5.jpg



    Sent from my iPhone using Tapatalk
     

    outrider58

    Eats Bacon Raw
    MDS Supporter
    Jul 29, 2014
    49,818
    John
    What OAL did you use?
    I do have enough H110 to make up a test batch to shoot and up to 120 rounds


    Outrider, per post #4 when loading chamber of the rifle
    See pic below (exposed lead on left side).

    Lead hardness is about 10-12


    I think I have a die I can use to add a flair for seating easier

    b7b77ee1122a73cfc0b2f83fd37cc0e5.jpg



    Sent from my iPhone using Tapatalk

    I use Dillon funnel/flare in my 550 and the Lee Factory crimper on the final stage.

    I don't cast bullets so probably John would be a bigger help as far as lead malleability is concerned.
     

    John from MD

    American Patriot
    MDS Supporter
    May 12, 2005
    22,734
    Socialist State of Maryland
    John
    What OAL did you use?
    I do have enough H110 to make up a test batch to shoot and up to 120 rounds


    Outrider, per post #4 when loading chamber of the rifle
    See pic below (exposed lead on left side).

    Lead hardness is about 10-12


    I think I have a die I can use to add a flair for seating easier

    b7b77ee1122a73cfc0b2f83fd37cc0e5.jpg



    Sent from my iPhone using Tapatalk

    I'm sorry, I was looking at the 160 and missed the .309. That is a completely different bullet than the one we use in 300BO. The bullet we use is .312-160. I have tried the .309-180 which has the same profile as your and it did the same thing and would always jam.

    The .312 - 160 was designed by Ed Harris for the SKS. When the 300 BO came along, those of us who used it in the SKS tried it in the 300 BO and it worked.
     

    John from MD

    American Patriot
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    May 12, 2005
    22,734
    Socialist State of Maryland
    No, I size them down to .310 with a Lee sizer while watching Combat on TV. :D

    For the .312-160, the COAL is adjusted to what will feed in your mags. I like the Lancer 300 BO mags as they have a very smooth feed. The magpuls work but seem to give me more friction and my last round doesn't lock back when using them.

    Do you have carbine gas or pistol gas?
     

    Melnic

    Ultimate Member
    MDS Supporter
    Dec 27, 2012
    15,282
    HoCo
    SBR is Pistol length gas and Rifle is Carbine length gas
    Both Rifle and 10.5” SBR will cycle 220gr subs I got from Tom Kat
    Both are 1:8 twist


    Sent from my iPhone using Tapatalk
     

    John from MD

    American Patriot
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    May 12, 2005
    22,734
    Socialist State of Maryland
    I have found that the carbine length gas likes 1680 better than H110 using a 150 gn bullet. For my 16 inch carbine gas barrel, I had to juggle the spring weight to get it to work reliably with H 110. Accuracy with a 1 in 8 twist and cast bullets without serious culling is still 2 MOA at 100 yards with a Sig Romeo sight. If I use 125 gn factory loads and a scope, my barrel will give me sub 1 inch groups off the bench.
     

    Melnic

    Ultimate Member
    MDS Supporter
    Dec 27, 2012
    15,282
    HoCo
    I'd be happy with 2MOA and PC bullets.
    I do have a lighter spring on the lower that I use on my dissipater upper.
    I have more uppers than lowers so I pick and choose the lower to match the upper.
     

    John from MD

    American Patriot
    MDS Supporter
    May 12, 2005
    22,734
    Socialist State of Maryland
    I think I also use a H3 buffer with the carbine gas and H110. If you use 1680, you don't have these problems. However, 1680 is a hard powder to find since Accurate sold out to Western Powders.
     

    Melnic

    Ultimate Member
    MDS Supporter
    Dec 27, 2012
    15,282
    HoCo
    so, I made the jump and ordered 2 molds direct from Lee website.
    Low and behold, already have a tracking # from Lee.

    90307 MOLD DC TL309-230-5R 1
    90361 MOLD DC CTL312-160-2R

    I can always use the 312 mold for my Mosins eventually (John (think it was you), still have not finished the pulled surplus I got from you years ago on a trade).

    I however right now only have a 309 sizer

    I played around with my existing coated bullets which are gas checked. So long as I champhered the inside of the neck, it does not scrape any coating off. I seated 4 bullets and then pulled them to inspect. I however think I'll give the cases a kiss with the universal expander in addition to champhering them.
     

    inkd

    Ultimate Member
    Aug 4, 2009
    7,512
    Ridge
    John
    What OAL did you use?
    I do have enough H110 to make up a test batch to shoot and up to 120 rounds


    Outrider, per post #4 when loading chamber of the rifle
    See pic below (exposed lead on left side).

    Lead hardness is about 10-12


    I think I have a die I can use to add a flair for seating easier

    b7b77ee1122a73cfc0b2f83fd37cc0e5.jpg



    Sent from my iPhone using Tapatalk

    Have you had luck with any round nose bullets? I have the weirdest issue with my .300Blk if I try RN bullets. I can get through the whole magazine and the last one will fail to feed, every time. I doesn't matter if I have 30 rounds, 5 rounds, 10 rounds or whatever, that last one will always get hung up.
     

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