300 Blackout load data and questions

[localbrew]

So I've been search this forum as well as various other forums and the data I'm finding varies. I'm starting to load 300 blackout and have some questions on powder loads.

I have CFE BLK (I know may not be the best powder) but it's what I have for now.

I have Berrys 220 gr bullets and I'm loading them at 2.172 O.A.L. crimped.

My question is what should my starting powder drop be, I've seen some say 11 grains and some 12.2 etc. I want subsonic loads and I'm using a 9" BCM upper suppressed. I'm not hunting, just using it out at the range so looking for as much quietness as I can get. Not shooting anything over 100 yards either.

I appreciate any and all input, I will be getting A1680 in the future after I burn through my CFE BLK powder.

 

[Rsadams]

Buy several loading manuals and read them , you can't have to much data.... They will probably all have different data as far as beginning and max charges because manuals are just a safety reference in reality.. You will have a hard time finding book data that matches up with each other so I like to use the book for the bullet I will be using... IE , Hornady manual for Hornady bullets , Sierra manual for Sierra bullets etc etc... There's manuals out there that have sub sonic data... I know for some sub sonic rifle loads they use pistol powder BUT if you load up a rifle round with pistol powder not knowing EXACTLY what you're doing you will probably die... AT best lose you vision and/or fingers , it will be bad so don't...

I use berry bullets for pistol but not for rifle , their pistol bullets I treat as lead bullets and load with lead data I have no clue for berry rifle bullets.... If it were me I would buy a Hornady reloading manual and then some Hornady fmj bullets and start from there , you can use the berrys later when you figure out exactly what's up....

For instance , in 10mm using a Hornady fmj and 10.5gr of powder the speed was one thing...When I switched to extream bullets of the same shape and weight 10.2grs was faster than the Hornady fmj bullets because the extream and berrys bullets act like a lead bullet not like a fmj if I would have loaded them to a full power fmj load i would have probably blown up the gun.... If you don't know why then you definitely need to do some reading.... DON'T DO ANYTHING IF YOU'RE NOT 100 PERCENT SURE ABOUT WHAT YOUR DOING AND WHY..... Reloading is a safe hobby but you can make very serious mistakes in the blink of an eye.. Start low and work up is some real good advice....

 

[Lynn Brase]

I have a question, why would A1680 be a better powder? Same velocity at a higher pressure than cfe black as per Hodgdon reloading site? If you have not seen their website just look it up. Plus its free.

 

[Rsadams]

I have a question, why would A1680 be a better powder? Same velocity at a higher pressure than cfe black as per Hodgdon reloading site? If you have not seen their website just look it up. Plus its free.

Exactly , and exactly why I put what I did in my post.... Plus I am going to add do not use other people's data off the Internet.... I know reloaders that it's amazing they haven't killed themselves yet and I would never fire one of their rounds... Their great people but horrible reloaders....

 

[localbrew]

I have a question, why would A1680 be a better powder? Same velocity at a higher pressure than cfe black as per Hodgdon reloading site? If you have not seen their website just look it up. Plus its free.

No personal experience with this one, others have said CFE BLK is louder and doesn't meter as well as A1680, so I'm just reiterating what some have said. Also they said it was dirtier.

As for reloading, I'm not a beginner and I have several manuals/handbooks already. I'm simply looking to understand what others have tried and liked. I've been reloading .223 and other calibers for years, I'm now just starting to reload 300 blackout. I'm very precise with my data, I case gauge every single case I reload and I don't just whip through on my Dillon press, I take my time. I process all my own brass as well, which means inspecting every case. I also am not one to experiment with powder such as you suggest pistol powder in rifle cartridges, nor do I swap primers. To your point, I'm looking to hurt myself which is why I stick to to basics, tried and true

 

[6Creed73]

I've loaded 300BLK with A1680, CFE-BLK, and H110. By far A1680 is the best I've used for subs. CFE-BLK is dirty and loud and I get cycling issues with H110 at subsonic speeds. I no longer use CFE-BLK because it's just not that good, I use H110 for all of my supersonic loads and it's a great powder for that. If you'll be loading a lot of subsonic, I suggest getting some A1680.

As far as load data, just do a powder ladder. I wouldn't rely on anyone else's data.

 

[localbrew]

I've loaded 300BLK with A1680, CFE-BLK, and H110. By far A1680 is the best I've used for subs. CFE-BLK is dirty and loud and I get cycling issues with H110 at subsonic speeds. I no longer use CFE-BLK because it's just not that good, I use H110 for all of my supersonic loads and it's a great powder for that. If you'll be loading a lot of subsonic, I suggest getting some A1680.

As far as load data, just do a powder ladder. I wouldn't rely on anyone else's data.

This is great and I appreciate it. And yes I’m only planning on loading subs for 300 bo. I’ll pick-up some of the A1680. I was going to ladder up whereas others have said to ladder down. I prefer the more cautious approach

 

[6Creed73]

This is great and I appreciate it. And yes I’m only planning on loading subs for 300 bo. I’ll pick-up some of the A1680. I was going to ladder up whereas others have said to ladder down. I prefer the more cautious approach

I actually ladder down with 300BLK. Pretty low chance you'll be at any risk of over pressure and I'd prefer not to stick one in the barrel by starting too low.

With CFE-BLK, I'd probably start at 12.5gr and work down.

 

[P1ZombieKiller]

I also use A1680. I found it to be as accurate subsonic as it is super sonic. I use 208 amax at 10.4 grains puts it just under 1000 fps. I could go a little more and still be sub, but the accuracy is less.

Look up @dellet and read some of his stuff. It helped me alot. I am no where near the shot he is, but I am happy with 2" groups at 100 yards. I dont shoot much past that except for steel plates.

Here was my load development targets. These were at 50 yards, but very transferable to 100 yards.

 

[P1ZombieKiller]

Here is a 100 yard target.

 

[Lucky6547]

I also use A1680. I found it to be as accurate subsonic as it is super sonic. I use 208 amax at 10.4 grains puts it just under 1000 fps. I could go a little more and still be sub, but the accuracy is less.

Look up @dellet and read some of his stuff. It helped me alot. I am no where near the shot he is, but I am happy with 2" groups at 100 yards. I dont shoot much past that except for steel plates.

Here was my load development targets. These were at 50 yards, but very transferable to 100 yards.

View attachment 1474054
View attachment 1474055
View attachment 1474056

What twist?

 

[dellet]

If you spend any time at all working with 300 Blackout, you will go crazy. There are no rules that you can apply, that there will not be an exception for. It can be frustrating, it can also teach you a lot about internal Ballistics if you are open minded and want to learn.

Just as an example, to do you ladder up or down for subs?

It’s a trick question, it depends on the powder used. With a slow burning, low pressure powder like CFE BLK, I would work it down. There is almost zero chance of an over pressure load, and a high chance of a stuck bullet. With low density loads I have seen velocity swings over 300 fps with CFE BLK. With a long barrel that’s a good chance of a squib.

Fast pistol powders like #9, work it up. Not much chance at a squib, and plenty of chance for a load over 50,000 psi.

1680, could safely go either way.

Most manufacturers load data for subsonic loads is complete BS. Hodgdon is among the worst. Old Accurate powder data, which is still available online was some of the best. Sierra bullet data is probably best currently available.

If you look at Hodgdon data, you find that max loads for Sub-sonic loads are based on velocity, not pressure. You have no clue what a safe max load is, and for the most part heavy bullets, 200 grains and up, are not listed for supers. That is a serious bit of missing information.

Old Accurate data had categories for both sub and super with pressures listed for both, so you could extrapolate safe loads.

Sierra gives you max loads based on pressure and velocity, for all bullet weights.

This data point, max pressure, becomes vital with barrels shorter than SAMMI test length of 16”. If you look at data that is capped at 1050 fps in a 16” barrel, and shoot a 9” barrel, you might stop at the max load, and only attain 900 fps. With a max pressure of 30,000 psi. If you’re not smarter than the data, it becomes frustrating.

Most people who shoot sub sonic are looking for quiet, here is why CFE BLK misses the mark, and why people gravitate towards faster powders.

Smokeless powder needs pressure to burn correctly. As a rule of thumb, the higher the peak pressure, the cleaner it burns, the higher percentage of the powder charge burns, and the lower the muzzle pressure is.

The less unburned powder coming out the end of the barrel, with less pressure relates to the less muzzle flash and and less pressure that the suppressor has to mitigate. That means a quieter shot.
Since the suppressor creates a lot of back pressure, that means more of the unburned powder blows back into the action and stays in the barrel creating fouling. In a semi auto it also means it blows back out the ejection port into your face. You can have more noise coming out the ejection port, than the end of the suppressor.

So with a load of even 1680, and a 200 grain bullet, you will be around 11 grains with an 85-90% burn of the powder charge, CFE will be 80-85% of 12 grains. Compare that to #9 and 95-100% of 8 grains, in a 9” barrel.

Quickload or programs like it are your friend, to sort this out.

What powders like 1680 and CFE have going for them is that they will easily cycle even the the most sloppily put together AR under almost any conditions. The faster the powder, the harder the load is to tune, and the more precise the rifle needs to be assembled. With load matched to bullet. This is where most people bad mouth the cartridge. They shoot off the shelf ammo and are disappointed with the results, more so with subs. If you’re not afraid to step outside the box, can safely navigate hand loads and have reasonable grasp of how the manipulate the powders pressure curve with seating depth, the cartridge can be a handloaders dream. If all you have ever done is look at numbers in a book and assemble cartridges, it’s going to be a very frustrating experience.

I use CFE BLK a lot as an example of marketing gone wrong. Testing the powder when it first came out, I used the book data for a 208 ELD. Got 3” groups at 50 yards with an ES around 200 fps. Dropped the powder charge 1/2 grain, seated the bullet on the powder by shortening the COL something like .150” and it was about 3/4” group with an ES around 40. This is what I mean when I say you have to be smarter than the published data.

For what it’s worth, 1680, and H110/296 are probably the two most versatile powders for the cartridge. Both work very well sub and super. I use 1680 almost exclusively for supers 150 grains and above. H110/296 for subs in my carbine gassed barrels. Pistol gassed barrels get faster powders for subs.
Bullets under 150 grains get H110/296 for supers.

Short answer to your original question, if you can’t slightly compress CFE BLK with your chosen bullet at a length that will cycle and keep the velocity sub-sonic, I’d change powder or bullet. It’s just not worth the grief.

 

[P1ZombieKiller]

What twist?

This rifle is 1:7

 

[dantiff2]

Black Out

300 black out, blk out

www.acmebullet.com

 

[padom]

I've strictly loaded and shot 300blk supers for many years using H110. Specifically the 125smk and 125tmk.. I'll always heard 300blk wasn't accurate, it was just a fun range toy.

I set out on a mission to find out going through various bullets and powders with horrible results so I turned to the barrel. Went through 3 different barrels and was unhappy with the results. I finally said 1 more barrel and thst barrel proved to be the key. It was a Rainier Ultramatch 10.5" 300blk (shilen blank). I've even tested their newer Ultramatch Mod2 (criterion blank) and it shoots just as good.


Here my initial testing first shots down the barrel with 125smk working from top left and moving across and down...

https://imgur.com/K4NNhBC

Here is my 125 TMK load workup

https://imgur.com/SC8J3FG

And here is my final 100yd load confirmation test. 7x5 AGG 0.521".. stupid accurate

https://imgur.com/scIEA5v

I didn't build this gun for long range precision. I wanted head shot accuracy from 100yd and in. But since I was testing accuracy, I temporarily put a Gen2 Razor on it to see what it could do during initial load workup along with bipod and rear bag.

Seeing how accurate it was, my buddy and I one day said let's see how this 125 TMK load holds up at distance. We were on a 200-500M range. I had zero issues going 5 for 5 on steel @ 200, 300, 400 and the ram at 500M.


The 125smk is a accurate plinking bullet but the 125TMK expands like crazy. It's what black hills loads in their 300blk defensive ammo. We did some back yard expansion testing with wet phone books, denim and water jugs.. the 125smk stayed 100 together and just bend like a banana. The 125 TMK expand like a 9mm HST pistol round with sharp pedals opened up.


Last year I decided to play with some 300blk subs... I was really surprised with the accuracy. 220smk and CFW Black. Stupid quite too.

https://imgur.com/6hlTO0w

 

[localbrew]

@padom and @dellet and all the others thank you, this is very helpful and I appreciate the information.

Since I'm running a 9" BCM which are notoriously over gassed to start with and suppressed, I'll start at 12.1 and work down from there. I'm using Berry's bullets 220 gr. with a COL of 2.172" and crimping. I figure I should be pretty safe to not get a squib with that short of a barrel and staying in the 11 - 12 gr. of CFE BLK. I will only run subs in this rifle and don't plan on reloading any supers, my main goal is to get it as quiet and accurate as possible. I've got 3 lbs of CFE BLK so it's going to be a bit before I start testing A1680. Here she is below, the only thing I'm going to swap is I'll be putting my PERST laser on this one to slim it down a bit up front.

 

[MSS]

I've strictly loaded and shot 300blk supers for many years using H110. Specifically the 125smk and 125tmk.. I'll always heard 300blk wasn't accurate, it was just a fun range toy.

I set out on a mission to find out going through various bullets and powders with horrible results so I turned to the barrel. Went through 3 different barrels and was unhappy with the results. I finally said 1 more barrel and thst barrel proved to be the key. It was a Rainier Ultramatch 10.5" 300blk (shilen blank). I've even tested their newer Ultramatch Mod2 (criterion blank) and it shoots just as good.


Here my initial testing first shots down the barrel with 125smk working from top left and moving across and down...

https://imgur.com/K4NNhBC

Here is my 125 TMK load workup

https://imgur.com/SC8J3FG

And here is my final 100yd load confirmation test. 7x5 AGG 0.521".. stupid accurate

https://imgur.com/scIEA5v

I didn't build this gun for long range precision. I wanted head shot accuracy from 100yd and in. But since I was testing accuracy, I temporarily put a Gen2 Razor on it to see what it could do during initial load workup along with bipod and rear bag.

Seeing how accurate it was, my buddy and I one day said let's see how this 125 TMK load holds up at distance. We were on a 200-500M range. I had zero issues going 5 for 5 on steel @ 200, 300, 400 and the ram at 500M.


The 125smk is a accurate plinking bullet but the 125TMK expands like crazy. It's what black hills loads in their 300blk defensive ammo. We did some back yard expansion testing with wet phone books, denim and water jugs.. the 125smk stayed 100 together and just bend like a banana. The 125 TMK expand like a 9mm HST pistol round with sharp pedals opened up.


Last year I decided to play with some 300blk subs... I was really surprised with the accuracy. 220smk and CFW Black. Stupid quite too.

https://imgur.com/6hlTO0w

Twist rate?

 

[padom]

Twist rate?

1-7.5

Rainier Arms Ultramatch MOD2 300BLK Barrel - 10\

Rainier Arms Ultramatch MOD2 300BLK Barrel - 10\

www.rainierarms.com

 

[Konocti's Wigwam]

With CFE-BLK, I'd probably start at 12.5gr and work down.

Not a very good approach, the Hodgdon site shows 12.1 grain as max for a 220 grain projectile.

 

[localbrew]

Not a very good approach, the Hodgdon site shows 12.1 grain as max for a 220 grain projectile.

See dellet's comment above; doesn't sound like Hodgdon is that great in terms of their data. I think you'll just get super sonic if you go over the 12.2 range like some have reported. Other things will increase the velocity as well, crimp, suppressor etc.