300 blackout load data

blackmaxx85

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This is my first post as I am new to the firing line. I just got 500 130gr sost bullets in and need some help with powder, charge weight, and oal. I also got about 300 125 smk to use too.
Any and all help or advise is welcome.
 
What powders do you have??

Im assuming this is for loading SUPERSONIC ammo for an AR??

You might want to check out 300blktalk.com. Im on there under the same name. LOTS of good load data for most bullet weights. 90gn-245gn. Mtpl powders. COAL advise, etc.

Im traveling and dont have my notes with me, or i'd throw out some charge weights and powders

I know ive got recipies for the 125SMK with H110 & 4227 that run good in my 9" AR. My COAL is right at 2.26 (max mag length) and i run P mags in my blkout.
 
For supersonic loads, Just about any fast rifle powder will work.
Usually between 16 and 17.5 gr of most.
300 Black out is real easy to load. It uses a small case so all loads will be in the 90% plus fill rate.

H110, 296, 4198, 4227, RL-7, 5744, Lil Gun are all good powders.
The most accurate loads will usually be about a grain under the max load. I load 125gr pills ahead of 16.5gr of any of these powders and get pretty much the same results. RL-7 being the most accurate but the dirtiest loads. While Lil Gun gives you a faster load than any of the others. Usually at least 100 fps faster. but not quite as accurate.
 
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I've found Lilgun to be the most accurate in my Ruger RARR. 18.1grns with a #41 primer behind a hornady 125 SST COAL 2.100, works great for me. this is however above published data USE AT YOUR OWN RISK!! I RECOMMEND STARTING LOWER AND WORKING UP.
 
I use Lil Gun for lightweight Supers that I wanna run HARD!!! I use H110 for 125gr+ Supers running at a good velocity. I use 4227 for 90% of loads, sub-sonic 230gr cast-lead to 125gr Supers, it is the most comfortable and versatile 300BLK powder in my opinion, always gets my rifle to cycle without coming even close to max loads/pressures, case capacity can be an issue with lighter loads if your wanting full-throttle bullets. NOTHING BEATS LIL GUN FOR VELOCITY!!!! if I was making hunting rounds, lil gun would be my choice. If you have powders on hand and are in need of specific data that has been tried and true, let me know what you got. If you are going to buy powder and just want to start out with good plink loads, grab the 4227, it's widely available and safer than others. 300bk can be a chore to reload, but it's not really any worse than any other medium cartridge, it is most difficult when riding the fine ine between staying "sub-sonic" and reliable feeding/cycling, supers as the same as any other bullet.

p.s. I also use mag pistol primers
 
Yes sharkbite it is a supersonic load for an ar.
I don't have a powder for it yet, as I reload for 223, 270, 308, 45 acp, 357 mag.

Thanks for all the help and starting point superspirit and coz.
 
your 357 powder should be fine, so long as they are actually magnum powders and not 231/hp38 or TiteGroup or something similar. Most all "magnum" pistol powders run in the 300BLK.
 
if have neither, H110 is a good versatile powder as well, just not as comfy as 4227, but not as harsh as lil gun. I would save the lil gun for hen your a little more experienced with reloading 300blk, ut that's just my opinion, you may well do just fine with it. but it does have a small window of running great, running hot or just running rampant. my accuracy load is Lapua Cuting Edge 90gr .308 bullets, with max capacity of lil' gun, fun round and blows those watermelons to pieces.

but as a good beginner load, any of the 110-125 BLK bullets with H110 will be very simple and have lots of data to look at. Lots of people obsess over 2400 and 1680 for sub-sonics as well. also lots of data exists for the 147gr pulls, generally with H110 as well. Also look for AA#9

blue dot is sometimes ud in sub sonics, not very popular though, but I see a od for 208gr AMAX starting at 7.0 and maxing at 10.0 with accuracy in the 8-9gr range, will it cycle?not sure. really only see Blue Dot being used in sub-sonic "bolt-action" 300's. GOOD LUCK, have fun and be patient.

are you forming your own brass?
 
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I finally was able to pick up some 4227 to start some load development with. Another question is what depth should I seat the bullet to. Hornady manual states 2.100 for 130gr bullet oal. The federal mk319 mod 0 sost bullet is 1.0185 long, I was going to seat the bullet to its first groove for a oal length of 2.150 and start at 14.5 grs of 4227 for first load. Does this sound good or bad?
 
AR's will limit COAL to about 2.26 or shorter. I like to run my bullets on the longish side. I think they feed better that way.

I load my 125SMK's to that length over 4227 and H110. So far that has been completely reliable. The H110 load gives higher velocities then can be achieved with 4227, but for plinking/training the 4227 load is fine.

I dont have access to my load data but most reloading books will give this data.
 
i have a rem md 7 modified by aac in 300blk and load 17.5 win 296 with a nosler BT 125gr bullet. and it shoots to the same POI as rem factory 120 gr OTFB bullets. the rifle is good for groups better than a inch. i just recieved 500 300blk cases reformed from .223 that are prepped( formed,deprimed sized and cleaned) for 72.20 delivered. the cases are ready to load and as i don,t have dies for the 300blk i use the seat die for the 762x39 with no problems at all. eastbank.
 
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