Pick one bullet for 300 Blackout supersonic

[Elkins45]

I have accumulated far more expensive custom molds than a human should ever have to buy in a quest to have the best and most accurate possible subsonic suppressed Blackout load for urban hunting and quiet shooting with a 10” SBR. That’s a quest that may well continue for years.

I also have a 16” upper that I’m planning on dedicating just to AR practice, plinking, blasting and banging around. As such, I want to settle on one load for it and then crank them out in quantity. One requirement is that I would prefer something that is available in a 4-6 cavity design. Right now my three most likely contenders are:

1) Lee 155-2R. I already have a six cavity and it shoots well.

2) NOE 175 Saeco clone HP. I have an RG4 version. It’s a hollow point, so it might have feeding issues....haven’t tried it yet.



3) Original TL version of the Ranch Dog 165. I have a six cavity. Because it’s a TL design I would probably use the HiTec coating on them. The flat point might not be ideal in an AR.

Are there any other designs I should think about? I own a few other multi cavity 30 caliber bullets, but most are heavier than the midweight designs I would probably prefer. For volume casting the lighter bullets can save an appreciable amount of alloy.

 

[mattw]

Yes, look at the NOE 311-152-sp1... it shoots very well. Also should look at the Accurate 31-150W. The reduced nose diameters really help with feed.

Kinda crappy photo, but here is the NOE and it shoots really well! I push mine up around 1850 fps. I think they would go faster, but shoot well at that speed.

 

[Bruce Drake]

If you can find it an ideal/lyman 311359 mold, it puts out a 120gr spirepointed bullet that is really nice for a supersonic round in 300BLK. or if you PC Coat them, a Lyman 311410 drops at 130gr, but many of those molds were bevel based and not designed for use with gaschecks which I think you should still keep at less than 1600fps unless the PC coating also covered the base of the bullet to provide some protection.

I've had decent luck using Lees 155gr Spitzer bullet with my 300BLK Ar Upper in super-sonic loads but I like the other two molds above for that along with Lee's 180gr RN .309 bullet seated deep in the cartridge for subsonic loads. I might be able to coax super-sonic speeds from the 180gr bullet but at this point, I know visually what I have loaded and I also know the lighter bullets can work to shoot accurately out to 200 yards.

Bruce

 

[fiver]

the 359 works great in the wifes 300 it won't chamber in mine.
mine likes the rcbs 165 silhouette bullet, my buddy's rifle won't chamber it,, period. well maybe with a hammer.

 

[Ian]

Anyone try the Lee C309-120R?

 

[mattw]

The 311359 will chamber in mine, does take some nose damage if the length is not perfect.

 

[popper]

I use the 31-142C PB, push it to 2100 fps PCd. You need to find the throat size as most of the bullet sits there, not in the bore. I also use a RD style with slightly smaller meplat that works (AR15) but look at the extension feed ramps - if wide cut OK else stay with pointy or small meplat. I find that large number of cavities gives me poor sprue cut - one side is hard before the other end hardens. So all my PB moulds are 2x. Just poured half a pot (some 400) of the 142 and got maybe a dozen culls, mostly from bad pours. These are for plinkers in the 30/30 and accuracy tests are good so far.

 

[Ian]

Pour the whole row "bloop, bloop, bloop,..." etc. and then run the whole plate back across the stream to daisy-chain the sprues together into one long centipede. Makes great PB bullets that way.

 

[Josh]

31-155W from Accurate Moulds it's designed for the 7.62x40. It gives reliable feeding in an AR and a sizable meplat

 

[Hawk]

I run the 31-155W from Accurate, PC'ed, in my 7.62x40WT in the AR platform and have no feeding issues at all.
Mine cast at around 158 gr. from COWW at .310.
PC and size to .309 and load 'em up.

 

[popper]

31-155W is close to the 170 & 185 I use in the 30/30 and BO.
I choose the 142(145) as it's the higher impact effect and trajectory (BC) + it's PB. Case cap., pressure and mass for the BO. 40wt can prob. go with the 150-160.

 

[popper]

Ian, that was my old Lee RD 6x mould and just got to much for me. It didn't really fit my marlin either so down the road. I just use 4x now that I can handle - pistol or GC only. These are grooveless for PC.

 

[L Ross]

How about the 30 XCB mould? I use it in a 7.62x39 in an AR with satisfaction.

 

[fiver]

good luck getting one of those.

 

[L Ross]

good luck getting one of those.

Has that become another one of "those" moulds?

 

[waco]

good luck getting one of those.

They been out of stock for awhile?

 

[Ian]

Hound Al about it on his forum and he'll bump it up the stock run list. I'm surprised he would let himself get low on those as much press as it gets.

 

[fiver]

last I looked he had like 1 plain base and one half and half brass mold.
I think it's got a lot more orders and want's than is let on, I get PM's about it 3-4 times a year, and about every time a thread about it gets started showing groups etc. at speed I get more.

 

[waco]

Nothing currently in stock.

310-165-FN-H3, NOE Bullet Moulds

 

[Bruce Drake]

7.62x41 (30 Herrett Rimless) with a poly-coated and gaschecked Lyman 311359 on the left (gray bullet) for one of my .30 caliber AR15s. Lee's 155gr .309" Spirepoint (gas checked base in orange paint) on the right. 2 coats of polycoating sandwiching a hornady gas check and then sized to .310" for both of them over 22.5grof AA1680. The -359 mold weighs at 124gr with the PC and gascheck. The Lee-309-155 mold weighs at 159grs with the. The Lee Reduction Formula places a projected muzzle speed at 2100 and 2000 fps for the two different bullets but same powder load, but I haven't had a chance to run them through my chronometer to verify the math in conjuction with the four inch decrease from a 20" rifle barrel to a 16" AR15 carbine barrel either.
modifications are needed to to use this cartridge with the AR15-style firearms: 1) recut the 300BLK chamber to a 30 Herrett chamber 2) 6.8 SPC magazines for mag changes. 3) and finally, 4) change to a 6.8 bolt head to reflect the different cartridge head dimensions in the brass.
30 Herrett Rimless brass is made from 6.8SPC brass that is necked up to 308 and then trimmed down to 30 Herrett length.

Bruce