bolt action blackout loads

• Feb 10, 2016

• #1

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

I've searched the web and came across a few loads for subsonics that do not involve having to make a bolt cycle. I'm starting this thread just for that purpose. These are loads that do not particularly have to work in an AR platform. Let me know what you have, what works, and what is junk. My two are below:

I started with Unique. 6.0 grains, a 208 HPBT, and CCI primer. The OAL was 2.210" This load shot about a 1.5" 4-shot group at 25 yards. Not good. Didn't play with it anymore. No chronographed loads.

Second load was 6.0 grains of Red dot. Same bullet, primer, and OAL. Shot approximately a .33" 4-shot group at 25 yards. Looks promising with the average speed of 965 fps. I loaded a few more to shoot at 100 yards. This is where the wheels fell off. The best 3-shot group I could put together was somewhere in the ballpark of 2.5". The worst was around 5".

I will be testing more loads/powder combinations in the future and will update the thread as I can. The rifle I am using is a R700 with a 16.5" barrel and an HS precision stock.

 

• Feb 10, 2016

• #2

M

mtlcafan79

Ultimate Member

Sep 11, 2008

1,284

PG

Some posts on 300blktalk about how Red dot isn't the best for the heavies (200gr+) accuracy wise. H110/296 seems to get it done. Been my experience too so far.Working on some Sierra 220 RN loads with N320. Super clean and quiet. I'd like to try some N110 too if I can find some.


These should get you going:

http://www.300blktalk.com/forum/viewtopic.php?f=141&t=92768

http://www.300blktalk.com/forum/viewtopic.php?f=141&t=82856

http://www.300blktalk.com/forum/viewtopic.php?f=141&t=91549

http://www.300blktalk.com/forum/viewtopic.php?f=141&t=97273

Trail Boss and XTP 90's or 110 Varmageddeon's are a hoot if you can find some.

 

• Feb 10, 2016

• #3

j8064

Garrett Co Hooligan #1

Feb 23, 2008

11,635

Deep Creek

I'm getting very nice accuracy with my 150gr 300BLK supers in my Ruger American using IMR4227:

JBs: Average 1774 fps with 17.0 grains
CBs w gas checks: Average 1735 fps with 16.2 grains

 

• Feb 10, 2016

• #4

Sticky

Beware of Dog

MDS Supporter

Mar 16, 2013

4,502

AA Co

Accurate 1680 has worked will with subs for me, but it's in an AR platform, so bolt function is also important.

10.7gr A1680 behind a 208gr Amax for a velocity of about 1050fps

Also been playing with 220smk's and LD 194ME's and several heavy casts for subsonic loadings

 

• Feb 11, 2016

• #5

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

Thanks guys.....when I google search, I find a lot of info on 300 blk out, but not too much along the lines of fast powders/big bullets. I'm going to play with unique a little more. I think I may need a bit more powder behind the bullet. I'll keep updating this thread with what works and what doesn't. I know I can always fall back on H110 and A1680 if things don't work out.

 

• Feb 11, 2016

• #6

Klunatic

Ultimate Member

Feb 28, 2011

2,923

Montgomery Cty

Lil gun works as well

 

• Feb 27, 2016

• #7

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

Today I played with unique and red dot some more. I jumped the powder on the red dot to 6.2 grains and 6.4 grains on unique. The red dot load sucked. About a 3" group at 50 yards and speeds from 999-1068. The unique proved much better. I had a 5 shot group under 1" at 50, but the speeds varied from 1010-1060. I'm going to keep playing with unique. I'll update again as I can. 2moa with subsonics and pistol powder will keep me happy.

 

• Mar 17, 2016

• #8

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

Reloaded 8 more of the 6.4 gr unique. Couldn't repeat the results. Loaded 8 with a longer oal. Didn't change much. Bought H110 yesterday. I'll update with that as I get time.

 

• Mar 17, 2016

• #9

S

Speed3

Ultimate Member

Aug 19, 2011

7,835

MD

PoPo3 said:

2moa with subsonics and pistol powder will keep me happy.

Click to expand...

Dang... I hope you find some better loads than 2MOA, I haven't attempted to get subs loaded yet, but that is disappointing if that is all we can get at 50 yards.

 

• Mar 18, 2016

• #10

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

Speed3, I am messing with powders way outside the range the blackout calls for. Unique is super fast burning compared to the normal blackout powders. I am starting the process with a more suitable powder (H110) and will expect much better groups. I will update as I get time. I was just hoping unique would work because the explosion would be reduced which equals quieter round through a suppressor.

 

• Apr 1, 2016

• #11

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

Bought some H110 and loaded a few rounds. Three of each at 8.8, 9.0, and 9.2. The below picture is a 3-shot group at 35 yards with the 9.2 grain load, OAL 2.260" and a 208 match bullet. Speed is a little low (980 fps), but if I can reproduce this load and it shoots as well as it did, I will deal with the lack of speed. Looks like it has potential.

 

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• Apr 3, 2016

• #12

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

retested the 208 bullet and 9.2 grains of H110 at 100 yards this time. This is the result. Did not run it over a chronograph, but I'm assuming it is a speed difference causing the vertical stringing (for some reason the picture is sideways). I have heard that throwing more powder behind the bullet helps with this so I will be testing a more stout load in the future. Going to try 9.4 grains and see what happens. More to come.

 

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• Apr 3, 2016

• #13

S

Speed3

Ultimate Member

Aug 19, 2011

7,835

MD

Getting consistent velocities has been a struggle in 300blk subs

 

• Apr 4, 2016

• #14

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

Absolutely. ive been using cci400 primers. Going to switch to federal a and see if the deviation gets any better

 

• Apr 4, 2016

• #15

S

Speed3

Ultimate Member

Aug 19, 2011

7,835

MD

You are close to me...if you want to try some CCI BR4 or CCI 41's I have some.

 

• Apr 19, 2016

• #16

M

mtlcafan79

Ultimate Member

Sep 11, 2008

1,284

PG

You can get consistent blackout loads, especially with a bolt or single shot. I've found it's all in the powder though. I have a load that is 6.4gr of VV N320 behind a Sierra 220 Pro Hunter. ES of 17 and a SD of 5 for a ten shot group. They fly just over 900fps and are significantly quieter than the same bullet at 1050fps.

 

• Apr 27, 2016

• #17

B

BW460

Member

Mar 8, 2012

89

Please be careful with light loads of H110. I know that is a long bullet, and I didn't run the numbers to see what kind of case fill that would be, but anything less than a 90% case fill with H110 is asking for big trouble. Search the web, - you can get a secondary explosion with less than 90% fill. H110 is my go to for supers, but it is not a good choice for subs.

 

• Apr 27, 2016

• #18

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

I just started running 4198 for my sub loads. Haven't had a chance to chrono yet, but decent groups and pretty quiet. Gonna save the H110 for supers. Thanks for the info

 

• May 4, 2016

• #19

P

PoPo3

Active Member

Oct 26, 2009

364

Hagerstown, MD

Haven't posted any results in a while, but I found an acceptable load. After 150 rounds of load development, my best/most consistent subsonic load is 11.2 grains of IMR4198 over a 190 SMK. OAL is 2.230". Getting consistent 1 moa groups at 50 and 100 yards. That being said I've shot two 5 shot groups at 50 and two 5 shot groups at 100. Haven't chronographed yet because of rain, but definitely subsonic. Not sure if it will cycle in an AR platform.