300 Blackout Accuracy
- Thread starter Bryan_t
- Start date
A lot of that is going to be dependent upon barrel length, projectile weight, twist rate and distance of target.
My Origin 16" 300blk will do sub-moa with most loadings between 110 and 130 grains.
The 300 blackout is not a .5 moa cartridge. It is a hard hitting shorting cartridge. For accuracy it will take a 16” quality barrel and great ammunition. I am building a a couple 16” uppers the first was a Wilson Combat 16”. It is sub moa with 110 Barnes tipped solids. I am still working on another using a 16” proof stainless in a JP thermal fit upper. I am hoping do better with it than the Wilson.
Sub-MOA is possible with the right rifle and ammo, but most people don't build precision rifles in this caliber.
I've never seen a AR-15 SBR /pistol that could put ten shots sub MOA consistently. Cherry pick a 3 or 5 to post on the Internet, sure.
I have four SBR that all shoot 1-1.5 with supers and 1.25-2.5 with subs. I occasionally get a lucky group, but I'll skip the Internet embellishments.
I have a bolt action Tikka with a preferred barrel that is 1 MOA with 110gr V-Max supers. Never tried to find a true match bullet though.
My goal was a great subsonic shooter, and I got it with 1 MOA using Lapua Subsonic 200gr bullets.
I've never seen a AR-15 SBR /pistol that could put ten shots sub MOA consistently. Cherry pick a 3 or 5 to post on the Internet, sure.
I have four SBR that all shoot 1-1.5 with supers and 1.25-2.5 with subs. I occasionally get a lucky group, but I'll skip the Internet embellishments.
I have a bolt action Tikka with a preferred barrel that is 1 MOA with 110gr V-Max supers. Never tried to find a true match bullet though.
My goal was a great subsonic shooter, and I got it with 1 MOA using Lapua Subsonic 200gr bullets.
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High Vel. rounds, I shot the best groups with using the old original Rem. 30-221 reamer in boltaction before the renamed/saami 300blk with it's added freebore to handle the longer heavy subsonic bullets .
BLK and Subsonic average group size I really have never had better than 2 MOA @ 100 yrd.
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Excellent, great shooting! That is far better than I have seen before. Actually exceptional shooting! What optic are you running?
Thats target was shot with my Gen2 Razor 4.5-27 with a bipod and rear bag from the bench at 100yds to confirm my load. It performed WAY better thsn expected. 125 TMKs hammer.
Because of this target, I took it to the long range to see what it could do with its permanent Leupold MR/T 1.5-5 CM-R2 and went 5 for 5 at 200, 300, 400 and 500M on steel.
I built the gun for 100yd and in head shots. I tested 4 barrels before this one to prove 300blk was an accurate cartridge or just a fun blasting cartridge. The first 4 barrels shot like shit. This one hammered.
Since then, Rainier sent me additional samples of the same barrel i tested, and they shot just like this.
This is the way
Rainier Arms Ultramatch MOD2 300BLK AR-15 Barrel - 10" Polished https://share.google/Hi7w9CJGn9Qn9CmUw
Little cheaper here
Rainier Arms AR Ultramatch MOD2 300BLK Barrel | Up to 10% Off w/ Free Shipping and Handling https://share.google/IhEfJSBtnp1yGcRHJ
Here another sample Rainier sent me, that I tested and compared to my first sample that shot that 7x5...
It was shooting 5 shot groups like this out the gate only 20rd down the barrel with 125 smk.... the TMK's shoot even better!
It was shooting 5 shot groups like this out the gate only 20rd down the barrel with 125 smk.... the TMK's shoot even better!
What is the rifle? Target says .02 off lands, what is your coal? I have a big jump on my 110g load.
I have a 16 inch DTA Covert that will shoot 9 out of 10 shots into around a 1/2 MOA group. But for some reason, the first shot (cold or warm bore) goes way low. Frustrating.
My older 300 Whisper bolt gun would often shoot Berger 215 or 230s into 1/2 MOA groups.
My older 300 Whisper bolt gun would often shoot Berger 215 or 230s into 1/2 MOA groups.
I have that same barrel and while mine has not shot groups quite as good, always makes me smile at 100 yards and somewhat farther. I have only shot mine with a 1-6 LVPO. I am referring to supersonic loads here.
Since this is the bolt action section, I secretly bought a Ruger RAR in 300BO that I have put many times it's purchase price in (stock, scope, suppressor, triggers, and small parts). That barrel will shoot! Believe or not, the barrel doesn't look bad at all inside. I can also run faster powders under heavy bullets subsonic loads than I can with an AR.
Since this is the bolt action section, I secretly bought a Ruger RAR in 300BO that I have put many times it's purchase price in (stock, scope, suppressor, triggers, and small parts). That barrel will shoot! Believe or not, the barrel doesn't look bad at all inside. I can also run faster powders under heavy bullets subsonic loads than I can with an AR.
This same barrel shoots 220smk with cfe black subs stupid accurate and quiet too.
If we are talking subs its pretty tough i think, but a fun and workable goal.
At 100 yards sub 2 moa consistently is fantastic with subs compared to what factory stuff usually does. Thats usually my goal and anything better is a bonus for practical subsonic work. 1.5 is attainable usually with some work. Better often is possible, but a good deal harder to nail down consistently.
Treat it like youre shooting elr and you have a great chance of making it happen. Heres what ive had work, assuming the rifle and optic are good to go.
Use good brass... prep the brass the best you can. Sort the brass by weight at least. If youre feeling froggy, sort fired brass by h2o capacity and make some nice little brass families. This dropped my SD more than anything else with subs. Seems the faster powders REALLY like uniform cases. Keep track of any that seem to shoot out of the group for velocity, cull them if repeatable.
Keep in mind we dont have to be at 1050 fps... sometimes it will shoot best at 975fps and be quieter.
Ive had good luck using faster and happily quieter powders that give decent case fill and are tolerant of low charge volumes. In the single shots, red dot, unique, herco, 800x, and blue dot have all been fantastic.
Blue dot and 800x have been loudest, but generally most consistent as long as i have good case fill with a 200g maker or similar.
Dont be an idiot about the fast powders. If you dont know what youre doing, then dont fuck with it until you really do.
Sort your bullets by weight and ogive if necessary depending on what youre working with.
Try different primers, and often dont worry about loading long coal rounds... eat up that case volume if your rifle will still shoot well with shorter overall cartridge length.
Random... saw the low first shot on the DTA mentioned above.. ive had a couple barrels that like a thin coat of lube on the jacketed bullets. Imperial or something like hbn or moly. Really made a difference for a couple barrels. Other times no change. Worth a shot!
You really want sub 10 Sd, closer to 5 is better, and should probably be your goal here.
At 100 yards sub 2 moa consistently is fantastic with subs compared to what factory stuff usually does. Thats usually my goal and anything better is a bonus for practical subsonic work. 1.5 is attainable usually with some work. Better often is possible, but a good deal harder to nail down consistently.
Treat it like youre shooting elr and you have a great chance of making it happen. Heres what ive had work, assuming the rifle and optic are good to go.
Use good brass... prep the brass the best you can. Sort the brass by weight at least. If youre feeling froggy, sort fired brass by h2o capacity and make some nice little brass families. This dropped my SD more than anything else with subs. Seems the faster powders REALLY like uniform cases. Keep track of any that seem to shoot out of the group for velocity, cull them if repeatable.
Keep in mind we dont have to be at 1050 fps... sometimes it will shoot best at 975fps and be quieter.
Ive had good luck using faster and happily quieter powders that give decent case fill and are tolerant of low charge volumes. In the single shots, red dot, unique, herco, 800x, and blue dot have all been fantastic.
Blue dot and 800x have been loudest, but generally most consistent as long as i have good case fill with a 200g maker or similar.
Dont be an idiot about the fast powders. If you dont know what youre doing, then dont fuck with it until you really do.
Sort your bullets by weight and ogive if necessary depending on what youre working with.
Try different primers, and often dont worry about loading long coal rounds... eat up that case volume if your rifle will still shoot well with shorter overall cartridge length.
Random... saw the low first shot on the DTA mentioned above.. ive had a couple barrels that like a thin coat of lube on the jacketed bullets. Imperial or something like hbn or moly. Really made a difference for a couple barrels. Other times no change. Worth a shot!
You really want sub 10 Sd, closer to 5 is better, and should probably be your goal here.
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I have a few 300 blackout's One being a Remington 700 It lives on a diet of 190 grain hornady sub-x I use 1680 powder for loading sub;s . Its purpose in life is toasting predators trying to eat my poultry . I am surrounded by timber so seldom do I shoot any further than 50-60 yds plus I am new to night vision so this has been an interesting learning curve .View attachment IMG_5414.jpeg
I tried H110, 1680, h4227, CFE Black, and blue dot for Subs (they all work for Supers more or less), but the problem with the above powders was the higher sd's.
I tried one of my favorite "medium" revolver powders (HS-6) and found great accuracy and single digit sd's. I prefer the Hornady SubX 190 for subs as they are relatively inexpensive, shoot very well, and if I ever hunt with it they would be a good choice.
I shoot my 300BO's at 100 yards at least and those high sd's showed up on target by the vertical spread. With HS-6 and it's single digit sd's, surprising groups are the rule. They will not cycle my 10.3" Ultramatch AR though.
