300 blackout subsonic for dummies
- Thread starter kooman
- Start date
gary paugh
New member
Start high and work your way down to sub vel loads that will still cycle your gun.
There are plenty of recipes out there, but they all behave differently in each gun. I would recommend getting a chrono and finding the combo that gets you consistently in the 1050-1100 fps range. Then adjust your gas block to properly cycle your AR.
I use lil gun and AA1680 for my subs.
I use lil gun and AA1680 for my subs.
Originally Posted By: Lazerus..recommend getting a chrono and finding the combo that gets you consistently in the 1050-1100 fps range. Then adjust your gas block to properly cycle your AR. I use lil gun and AA1680 for my subs.
+1,
also used Do63 that is very similar to 1680 for subs.. and use Lil-Gun for 110 gr supers.
+1,
also used Do63 that is very similar to 1680 for subs.. and use Lil-Gun for 110 gr supers.
Plant.One
Well-known member
you'll probably want to stay closer to 1020-1050 than the 1050-1100 range.
the closer you get to 1100 fps, the less atmospheric variation you'll have while the bullet stays subsonic. if you live in an area where it gets cold in the winter, and develope a 1100 fps load in the summer, it could quite easily go super on you in the dead of winter. i have a load that's 1053 fps avg that if the humidity is super high - like right after a rainstorm or when its foggy - i get supersonic cracks out of it.
as mentioned above - get a chrono. its almost mandatory for truly getting into the sub game. If you expect ANY kind of accuracy much beyond 50 yds finding a load in your gun with as low of an ES Possible is critical. Think single digits type ES. dont think it matters, try shooting a load with a 50fps ES at 50 yds. then repeat the same load at 200 yds. an inch group at 50 is going to look like a shotgun pattern at 200.
Besides that load data for someone else's firearm with chrono data may not work in yours.
I have two blackouts - a 9" pistol and a 16" rifle. i use the same sub load for both. that load has over 50 FPS variance between the two barrels. here's the shocker - the 9" barrel is the faster of the two.
regarding powders, 1680 is good, but tends to be fairly dirty. especially suppressed. DO63 is a lot cleaner, and runs about the same powder usage (i had to drop ~ .3 gr from 1680 data). 4227 should also give you some good results, along with a wider selection of powders. DO63 is commonly sold under the name Shooters World Blackout.
HTH
the closer you get to 1100 fps, the less atmospheric variation you'll have while the bullet stays subsonic. if you live in an area where it gets cold in the winter, and develope a 1100 fps load in the summer, it could quite easily go super on you in the dead of winter. i have a load that's 1053 fps avg that if the humidity is super high - like right after a rainstorm or when its foggy - i get supersonic cracks out of it.
as mentioned above - get a chrono. its almost mandatory for truly getting into the sub game. If you expect ANY kind of accuracy much beyond 50 yds finding a load in your gun with as low of an ES Possible is critical. Think single digits type ES. dont think it matters, try shooting a load with a 50fps ES at 50 yds. then repeat the same load at 200 yds. an inch group at 50 is going to look like a shotgun pattern at 200.
Besides that load data for someone else's firearm with chrono data may not work in yours.
I have two blackouts - a 9" pistol and a 16" rifle. i use the same sub load for both. that load has over 50 FPS variance between the two barrels. here's the shocker - the 9" barrel is the faster of the two.
regarding powders, 1680 is good, but tends to be fairly dirty. especially suppressed. DO63 is a lot cleaner, and runs about the same powder usage (i had to drop ~ .3 gr from 1680 data). 4227 should also give you some good results, along with a wider selection of powders. DO63 is commonly sold under the name Shooters World Blackout.
HTH
We don't have to worry about it getting cold and spiking our loads....lol. But great advice. It's good to heard from different parts of the country because I never would have thought about that as we do;t deal with it.
I am going to get some of that DO63 and try it too. Sounds like a winner because mine gets DIIIIIIIIRTY.
I am going to get some of that DO63 and try it too. Sounds like a winner because mine gets DIIIIIIIIRTY.
Originally Posted By: LazerusWe don't have to worry about it getting cold and spiking our loads....lol. But great advice. It's good to heard from different parts of the country because I never would have thought about that as we do;t deal with it.
I am going to get some of that DO63 and try it too. Sounds like a winner because mine gets DIIIIIIIIRTY.
The cold does not "spike" your load. The speed of sound varies with air density. Air density varies with temperature and humidity, a load that is subsonic but right on the edge can be supersonic with different atmospheric conditions. Still the same speed of bullet, but speed of sound varies.
I have to run about 1000fps to maintain subsonic here at 8400' of elevation and winter.
I am going to get some of that DO63 and try it too. Sounds like a winner because mine gets DIIIIIIIIRTY.
The cold does not "spike" your load. The speed of sound varies with air density. Air density varies with temperature and humidity, a load that is subsonic but right on the edge can be supersonic with different atmospheric conditions. Still the same speed of bullet, but speed of sound varies.
I have to run about 1000fps to maintain subsonic here at 8400' of elevation and winter.
Originally Posted By: koomanI am the dummy but I want to learn, I have the brass and the dies so does anyone have any load info to load subs? any help would be great. shooting them suppressed from an ar pistol
I liked 1680 and found that it would reliably cycle subs with or without the can on a 16" barrel (carbine gas, not adj gas block). I was in the 10.7-10.8 grains with a 208 a-max loaded at mag length. Velocity hovered in the 1040 ft/s range and was very accurate.
I liked 1680 and found that it would reliably cycle subs with or without the can on a 16" barrel (carbine gas, not adj gas block). I was in the 10.7-10.8 grains with a 208 a-max loaded at mag length. Velocity hovered in the 1040 ft/s range and was very accurate.
In my 10.5" pistol and 16" RARR, I found that working back to get velocity avg of 980 or a bit less using 1680 with a 208 Amax, gave me great accuracy and reliable function. In the cold temps, almost anything over 1020 was not quiet, sonic crack occurred randomly. Thus the reason my load development was done in the cold, Brrr. Winter coyote freeze [beeep] cold.
Plantone is right, 1680 is a bit dirty, but it just plain works. Now, if he would just send me a sample of Shooters World to try...
Plantone is right, 1680 is a bit dirty, but it just plain works. Now, if he would just send me a sample of Shooters World to try...