Cast 300 blackout load data

[Silence is golden]

Hi I just picked up a new AR15 in 300blk and I can't really find a lot of load data for it that will reliably cycle the bolt anyone have a favorite load it has a 16" 1-7 twist barrel and a carbine gas System
Jesse




The bullets I have are


LEE .312-155-2R


LEE .309-180-R


LEE TL309-230-5R


As for powder I have


IMR 4227


Varget


Red dot


Blue dot


Green dot


Bullseye


Trail boss


Unique


2400


Leverevolution

[wlc]

You will probably have the best luck with the 4227 with your sub loads for the lee 230 grainer. The latest Hornady book has a bunch of loads for the blk. I would suggest starting there. Another place to look is over on 300blktalk.com. Lots of knowledge over there concerning loads etc. for the blk. 'Lil gun, h110, and 1680 are some of the best powders while there are others that work you will probably find more loads using those. I've used RL7, AA5744, 'Lil gun, 4227 and 1680. 1680 works best for me with subs. I don't load supers.

ETA: some of the powders you have listed will make for some really quiet subs, but you can forget about them cycling the action.

[claude]

4227 in light loads will be dirty.

[Silence is golden]

The problem I have is that AA1680 is impossible to find and Lil gun/5744/H110 and RL7 aren't easy to find either I was lucky to find 2 pounds of 4227

[flyingrhino]

I use the C312-155-2R, sized to .309, 17.0 grains 4227 seated 2.055. Chrono's 1885. 17.3 grains gives me 1950 fps. Very accurate load. I powder coat and gas check. 16" 8 twist barrel.

[claude]

Don't misunderstand, 4227 is a good powder, but it likes it's pressure to burn clean, sub loads are low pressure and 4227 will not burn clean under low pressure, lots of smoke, unburned powder, and sooty gritty buildup. If you want to load subsonic, 4227 will be dirty, if you load supersonic, it'll clean up as the pressure rises, and burns very clean and consistent. YMMV, but this has been my experience and I have used many pounds of it, and I like it.

here is some data you may be able to use.

http://www.2ndefense.com/300-aac-bla...eloading-data/

[garym1a2]

I run this bullet with 15.0grs of 4227, my bullet is gas check conventional lube. my speed is only 1750fps. Since I wanted an economical(cheap) load I have went as low as 14.2grs with decent results. I use a carbine gas system 16 inch Midway barrel.

I use the C312-155-2R, sized to .309, 17.0 grains 4227 seated 2.220. Chrono's 1885. 17.3 grains gives me 1950 fps. Very accurate load. I powder coat and gas check. 16" 8 twist barrel.

[dh2]

To get the Lee 230 gr to cycle for me with W296 or H110 I have to go. 5gr over hodgon requemendation

[Jeff Maney]

Lee 312-155, sized to bore plus 0.001/0.002". H110/W296/16.0 grains, runs & shoots great in my DPMS 16" carbine.

Jeff

[kweidner]

depends on gas tube. Pistol or carbine? I have found pistol length to be much more forgiving. I do use a bit of 4227 in subsonic in my pistol length 10.5 and 16.5. runs fine but does not play ball well with carbine length tubes.
I hinestly believe manufacturers missed the mark and should have been honest with the world and said the best profile would have been a pistol length tube with selective gas system. It is really almost an outright lie that the carbine, mids, and rifle only need barrel swaps. The industry led the consumer to believe a barrel swap and you would get 100 percent reliability.

[Trinidad Bill]

I use 16.5gr of H-110 for 150gr jacketed bullets.

[Silence is golden]

bumped

[xacex]

I have used the red dot for subs, but it wont cycle your AR if that is what you are using to shoot them out of. Super quiet out of a suppressor if you don't mind working the action. I just bought 5 pound of RL-7 from Butch's reloading supplies so it is around. Cabelas had it last week, but it is now on back-order. I don't like the price, but it is out there. With the carbine gassed 300 BLK you are really limited as far as subsonic loading, but you should do OK with supers. The 4227 will do fine with the Lee AK 155 grain boolit. With the blackout and supers I just use starting jacketed data, and it usually is pretty close to accurate if I can get it to cycle. Your best accuracy will not be pushing the envelope with that one.

[Whistler]

I use 17.0gn 1680 equivalent powder with the LEE .312-155-2R. Reaches major power factor from my 18" and performs well.
I powder coat and gas check, sized to .311.

[ipijohn]

I do the same as this load except I size to .312 and don't PC the bore rider section of the boolit. 17 grn of 1680 under a Lee 312-155-2R

[Paulinski]

10.7 gr of 1680 with 247gr NOE. Cycles and locks on open 16" LMT MRP barrel with pistol gas length.

[flyingrhino]

I run this bullet with 15.0grs of 4227, my bullet is gas check conventional lube. my speed is only 1750fps. Since I wanted an economical(cheap) load I have went as low as 14.2grs with decent results. I use a carbine gas system 16 inch Midway barrel.

I'm going to try your load. Mine is also carbine gas system on a 16" barrel. I put a JP Captured spring in mine and have it tuned just right so it must be time to jack around with something! Anyway, I use my 17 grain load for hogs. They don't like it much.