.300 AAC Blackout Load Data

[Rumbler]

I have been doing some load development this week and have come up with a couple of notable loads in my opinion.

As always DO NOT consider these loads safe in your gun. Work up to these in the case of Supersonic velocities, and work down to them in subsonic velocities. Remember that a load below "manufacturers listed minimums" can be every bit as dangerous as loading beyond "manufacturers listed maximums".

The gun is a 16" AR platform. Standard buffer, carbine length gas system. The barrel is a CMMG heavy barrel in stainless steel with a 1:7 twist.

----------------------------
9.4gr Hodgdon H110
Winchester small rifle primers
208gr Hornady A-Max
2.260 COAL

1022
1038
1057
1066
1057
----------------------------

16.2 Hodgdon H110
Winchester small rifle primers
150gr Sierra Game King
2.140 COAL

1998
2009
2011
1999
2006
---------------------------

I have other loads, just gotta find the notes. Will add to this as I do. I have some 230gr, 168gr, 130gr data that will knock your socks off. Too. :p

[BlueBronco]

You have a shiney rifle barrel?

[Rumbler]

Uuuuum, yeah. :pde:

But I do carry a couple of different colors of drab paint in my big red range bag. Including flat black! :naughty:

[BR549]

Being a total newbie to reloading, I know nothing...on the lighter loads, subsonic, how much of the case is "empty" if there is less powder inside? If a case has a void in it, and the round lays on it's side with the powder sloshed up toward the front of the round, is there a risk of power not being ignited? I always wondered that. Most every factory load I ever took apart was full to the brim with powder.

[FLT]

The small capacity of the 300BLK is ideal for subsonic loads that is in fact one of the primary reasons it was developed. The loads that Rumbler list for the 208 grain subsonic load fills the case about half full and doesn't create a problem . The danger as he stated is that if you start at to low of a charge there is a danger of having a bullet get stuck in the barrel that is why you start a little high and work your way down to subsonic .

[Rumbler]

FLT is right.

But there is more to it than that. Depending on the load, bullet weight, and powder used, the subsonic .300 Blackout generated between 35,000 - 40,000 PSI of pressure.

Ain't no barrel going to stand that outside a ballistics testing lab where the barrel is 8" in diameter with a .308 hole through the center of it.


So . . . time in the bore, and gas expansion rate also comes into play. In the case of ALL the things we think of as modern firearms a great deal of science is put into the speed of gas expansion versus barrel length.

You can see this in action in any gun that shoots a ball of fire out the end when discharged. THAT is like smoking your tires at the drag strip; it looks cool, but it is actually not what you want because it is non, or even counter productive. That ball of fire is powder being burned AFTER the bullet has left the barrel.

Anyway, back on track . . . the problem with "below minimum loads" can be that the pressure spikes too soon. Before the container (the space behind the bullet to the back of the cartridge case) is large enough to accommodate it without catastrophic failure.

Remember that pressure/volume relationships are inversely proportional, and that resistance to flow is what causes pressure. The farther down the barrel the bullet gets the more pressure there can be without 'blowing up' the person or the gun.

It gets pretty scientific, right up until you 'go to far' then it simply gets really painful . . . or not.

[Rumbler]

18.2gr Hodgdon H110
Winchester small rifle primers
125gr Hornady SST
2.091 COAL (crimp to canelature)

2195
2198
2207
2200
2203
This is JD's hog busting load. He says "they don't take a step, they just roll over dead".
----------------------------------------------------------------------------

[FLT]

Rumbler are you using cases formed from 5.56 brass for these loads?

[Rumbler]

Yes. 100%

All NATO brass.

[marcus6176]

Yes. 100%

All NATO brass.
I did all the brass conversion for them. I knew it would not be long before mike went over to the black side ;)

[marcus6176]

Right now I am working on some loads that exceed 3,000 fps with no pressure signs

[Rumbler]

I wanna do that. With a 230gr bullet. :love:

And yes for sure, Marcus's brass is as good or better than any factory brass I have worked with. Because I tend to push the limits little stuff like overall case length is a critical dimension. It is also a good indicator of the quality of work put into the brass because that is a very easy place to get lazy.

Thus far, and I have loaded hundreds at this point, I have yet to have to reject or rework a single case because of an OCL issue.:hail:

[marcus6176]

230 gr bullet for a super? Wow! My only advice for that is to switc to a different powder other than h110. I would try lil gun because it is a little more forgiving when it comes to maxing out a load to try even push that heavy ass bullet for a supersonic

[FLT]

A supersonic load for the Sierra 220 grain MKHP is 15.6 grains of AA1680 with a 7 1/2 Remington primer loaded in A Remington 300BLK case to a over all length of 2.190 . A 16 1/2 inch barrel S&W AR 15 was used to record A average velocity of 1520fps. A Oehler 35P chronograph was used to record these velocities . The the air tempature was 70 degrees at the time they were recorded . This load was safe in the rifle used for these test there were no FTF or FTE the bolt locked open on the last shot. As always use at your own risk . Start at 10% under listed maximum load and work up.

[Rumbler]

Got this load proofed just the other day.

10.9gr of AA1680
230gr Berger Hybrid bullet
WSR primer
2.238 C.O.A.L.

1055
1047
1066
1049
1063

Hits like a sledgehammer at 100 yards.

Apparently my blackout is breaking in nicely. Carbine gas system on a 16" 1:7 barrel. No suppressor, but this load functions flawlessly. Feeds, extracts, locks the bolt back.

[Rumbler]

19.1gr Lil Gun
130gr "barrier" bullet*
Winchester Small Rifle Primer (WSRP)
NATO Brass
Medium crimp (Lee factory crimp die)
2.038 C.O.A.L.

---------------------------------------------------------------------------------

19.1 Lil Gun
110gr Nosler Varmageddon bullet
NATO Brass
WSRP
Medium Crimp
2.025 C.O.A.L.
-------------------------------------------------------------

* - Pulled carefully from MK319 Barrier Ammo. The best description of this bullet would be a "two bullets in one projectile" The front is an OTM, jacketed. The back is a solid copper 'slug'.

A couple of days ago JD (using my blackout) shot a full grown male hog right through it's armor. Entry and exit holes. Pig hit the deck, twitched a little, and expired. This bullet is no joke!

[Cattle/Horses]

I just ran across this link that I had saved. I shows the cross sections of a lot of various rifle and pistol ammunition.

http://www.ar15.com/ammo/project/Ammo_Cross_Sections/index.htm#9x18_Makarov

Thought some of you would find it useful also.

[Rumbler]

Latest . . .

20.2gr of H110
110gr Barnes TAC-TX
#400 CCI SRP
2.240 C.O.A.L.

The Barns data said this should run 2415FPS out of a 16" barrel. The problem - in my view - is that their recommended C.O.A.L. was 2.250 . . . or just exactly enough to touch front and rear of my USGI magazines. They would fit, but there was absolutely zero "wiggle room". SO . . . . I shortened them .010, dropped off .3 of powder and started working back up from there.

Where I ended is above. Chronograph said:

2450
2442
2460

I can live with that. For now . . . :cool:

[BR549]

Honest no BS question, assuming one had brass, what does it cost to get setup to reload, and then what does it cost per round to reload the 300 BLK?

[BR549]

I need a complete idiots guide to reloading setups, tools, extras, etc.

[Rumbler]

The honest no-bs answer to what it costs is: it depends.


I'd have to say that the price of bullets are the biggest variable. But that variable can be huge. Just a few days ago I paid $54.00 for fifty bullets. On the same day I paid $63.00 for 100. Last week, 1000 bullets for $150.00.

See what I mean?

It may be more illustrative for you to know that on average, a box of 300 BLK that sits on the shelf at $35.00 can be made identically for about ten to fifteen bucks. And the ammo you make, can easily be more consistent (consistency = accuracy).


Presses and peripheral equipment is also a variable, but the closer you can narrow down what you want to do - or not do - the more those variables can be narrowed down in terms of cost.


I know that this is no small task in itself, but if there is some time/day you can catch me sitting still with enough time to go over to the reloading room with you, I can show you basic to exotic and explain the differences to you. JD & Charlie have blessed me with an amazing facility to make/reload ammunition and given me the run of it.

I think that you'd be silly not to take advantage of seeing /fondling the equipment before you start making decisions regarding what to buy or not buy.

[BR549]

The honest no-bs answer to what it costs is: it depends.


I'd have to say that the price of bullets are the biggest variable. But that variable can be huge. Just a few days ago I paid $54.00 for fifty bullets. On the same day I paid $63.00 for 100. Last week, 1000 bullets for $150.00.

See what I mean?

It may be more illustrative for you to know that on average, a box of 300 BLK that sits on the shelf at $35.00 can be made identically for about ten to fifteen bucks. And the ammo you make, can easily be more consistent (consistency = accuracy).


Presses and peripheral equipment is also a variable, but the closer you can narrow down what you want to do - or not do - the more those variables can be narrowed down in terms of cost.


I know that this is no small task in itself, but if there is some time/day you can catch me sitting still with enough time to go over to the reloading room with you, I can show you basic to exotic and explain the differences to you. JD & Charlie have blessed me with an amazing facility to make/reload ammunition and given me the run of it.

I think that you'd be silly not to take advantage of seeing /fondling the equipment before you start making decisions regarding what to buy or not buy.

I'm in. I'll holler at you next time I head to the range.

[Rumbler]

10-4. :cool:

[mapper]

Any more load data?
I need to search for some for 147-150 gr ball..
But if you have tried any that would be great..
I found this....
http://www.ar15.com/archive/topic.html?b=6&f=42&t=414655

But I like to check multiple sources..

[FLT]

Hornady 9th edition. Accurate 1680 powder 15.4 grains 1500 fps. Starting load -- 22 grains 2050 fps. max load this is for a 150/155 grain bullet. Sierra manual A5744 powder 17.8 grains 1862 Fps. starting load--19.8 grains 2073 fps. max load also for 150 /155 grain bullet.

[Rumbler]

Check here. It is kinda the mother lode:

http://www.300blktalk.com/forum/viewtopic.php?f=141&t=81567

LOTS of loads for 150 . . . . and all the rest for that matter. :)






Any more load data?
I need to search for some for 147-150 gr ball..
But if you have tried any that would be great..
I found this....
http://www.ar15.com/archive/topic.html?b=6&f=42&t=414655

But I like to check multiple sources..

[Jas8340]

FYI: The 9th Edition of the Hornady reloading manual has some errata with the .300 BLK COL:

http://www.hornady.com/assets/files/9thEdErrata.pdf

[FLT]

Thank you.

[FLT]

Check here. It is kinda the mother lode:

http://www.300blktalk.com/forum/viewtopic.php?f=141&t=81567

LOTS of loads for 150 . . . . and all the rest for that matter. :) Damn . Mike I believe they have tried every combination of powder and bullet known to man. It's as you said the mother lode.

[Rumbler]

Agreed. I have gotten some great guidance from that data.:)

[Dale Gribble]

19.1 Lil Gun
110gr Nosler Varmageddon bullet
NATO Brass
WSRP
Medium Crimp
2.025 C.O.A.L.
-------------------------------------------------------------


Mike I'm getting ready to make this load. Its going to be in a 8" barrel. Obliviously I need to back off (10%, more?) but any other suggestions or updates?

[Rumbler]

Should be GTG, Dale.

Lil Gun is a great shorter barrel powder, and Nosler's data for that load says "18.0 min, 20.0 max" (16 inch pac-nor barrel) though at 20 grains it is a compressed load, which is why I backed off to 19.1. By my ciphering, using NATO brass anyway, that is the case "full but not compressed" point.

Believe me, even at 19.1 that load will knock the snot out of whatever you shoot with it.:cool:

[Dale Gribble]

Should be GTG, Dale.

Lil Gun is a great shorter barrel powder, and Nosler's data for that load says "18.0 min, 20.0 max" (16 inch pac-nor barrel) though at 20 grains it is a compressed load, which is why I backed off to 19.1. By my ciphering, using NATO brass anyway, that is the case "full but not compressed" point.

Believe me, even at 19.1 that load will knock the snot out of whatever you shoot with it.:cool:

Thanks.

[Dale Gribble]

My first 2 300 blackout rounds made with Rumbler Power.

https://lh6.googleusercontent.com/-gtKnOLge-_U/VLj-WygOOXI/AAAAAAAAJaE/wbu3I5KEu_A/s800/20150116_061539.jpg

The first round was test fired at 9pm last night. It caused a tear in the space time continuum, allowing me to have a conversation with Thomas Jefferson. When I told TJ the state of things in this country he was pissed and bitch slapped me, twice.

My reloading setup.

https://lh6.googleusercontent.com/-p2G_QC0pmdc/VLj-W1_ii9I/AAAAAAAAJaI/rsAbACqj_FI/s800/20150116_061552.jpg

[Danman]

Rep'd for TJ reference.

[Rumbler]

Nice !! :headbang::headbang:

Now, 998 more and you are ready for a day at the range! :goodjob:

[Dale Gribble]

Nice !! :headbang::headbang:

Now, 998 more and you are ready for a day at the range! :goodjob:



I think I will make a magazine or 2 full for testing before I go full retard!

[Dale Gribble]

BTW, by my calculations using Rumblers 19.1 grain lil gun recipe, with brass, the cost per round is .53 cents.

Once you reuse the brass (now its free) the cost is .33 cents.

Even cheaper if you don't over pay for your powder.

[Dale Gribble]

Marcus. I need a deal on some lead bullets.

[Rumbler]

Marcus. I need a deal on some lead bullets.


Me too!!

But they need to be heavy. :)

[JMW4570]

Have you tried these? Coated Missouri 245 grain bullets? https://www.youtube.com/watch?v=SGDenUyinAc

[Rumbler]

Have you tried these? Coated Missouri 245 grain bullets? https://www.youtube.com/watch?v=SGDenUyinAc

I just got some of their 250gr "pin buster" .452 hardcast. Lets see how they stand up to "Rumbler" loads.

[mlawrence]

These ( http://www.leatherheadbullets.com/products.php ) have a pretty good reputation at 300blktalk.com, but I haven't tried any yet.
I have 500 of these ( http://lucky13bullets.com/index.php?main_page=product_info&cPath=29&products_id=156 ) on order. Try coupon code 'ENOS' for 5% off.

[marcus6176]

How heavy mike?

[Rumbler]

200 on up . . . I figure if I'm going to shoot them subsonic they should at least be carrying all the energy they can have. :cool:

[marcus6176]

I am about to order a 240 gr hollow point mold. Just waiting for some more feedback on it, before I pull the trigger on Buying it.

[Rumbler]

I sure like the 230gr jacketed hybrids, which are the only heavy ones I have loaded. They hit haaaaard. I can only (joyously) imagine what a reasonably soft cast 240gr hollowpoint would do to a "target".

:headbang: