300 Blackout Load Data

I am starting this thread to post my results of loads I try good or bad for the 300 BLK. and everyone is welcome and encouraged to add load data from there 300 Blackout load results.

My 300 Blackout is built on a Spikes Forged Upper and Lower receiver with a RRA Chrome BCG and Wilson Combat 16" SS Match Grade Barrel.

First I wanted to try some 110 Hornady SP Bullets. Wanted a good cheap round to shoot and even hunt with. I wanted to hopefully get 2400 FPS out of it with minimal signs of pressure and good accuracy is a must. First i just wanted to find what loads would keep me in between 2300 and 2400 FPS no accuracy test until i find the load range I have to work with. I will be doing this with almost every .308 bullet available from 110 to 165 grains and will post results on this page as I go.

This took place on 8/4/11 at 80F and 60% Humidity

Hogdon H110 Powder loaded in PMC .223 brass sized by Lee 300 Blackout dies over Tula NCSR-223 primers. Hornady 110 SP bullets OAL 2.00

19 Grains. No pressure signs but a little slow rifle did cycle fine LRHO

1. 2266
2. 2292
3. 2262
4. 2253
5. 2258

AV. 2272
ES. 33.78
SD 14.59

19.5 Grains. In the fps range I wanted no pressure signs rifle ran well

1. 2276
2. 2292
3. 2281
4. 2313
5. 2345

AV. 2301
ES. 68.79
SD. 28.21

20 Grains. In the middle of fps I wanted rifle ran fine no pressure signs

1. 2344
2. 2369
3. 2377
4. 2360
5. 2358

AV. 2361
ES. 33.15
SD. 12.70

20.5 Grains. Started showing signs not bad but 2400fps :D

1. 2409
2. 2391
3. 2424
4. 2439
5. 2409

AV. 2415
ES. 47.72
SD. 18.05

I tried 21.5 grains but only shot one round very flat primmer it ran 2454 fps but I will pull the rest apart to hot for me :tdown:. I will load up 6 round each with 19.8, 20, 20.2, 20.5 grains of H110 they should all be above 2300 fps and see witch one holds the tightest groups.

WARNING! SOME LOADS IN THIS THREAD MAY EXCEED RECOMMENDED CHAMBER PRESSURE FOR THE 300 BLACKOUT. DESPITE MY BRASS AND RIFLE NOT SHOWING ANY SIGNS OF EXTREME PRESSURE, YOUR RESULTS MAY VARY. IF YOU CHOOSE TO REPRODUCE THESE LOADS, DO SO AT YOUR OWN RISK

I found a post on silencertalk touting Unique as a good subsonic load. I ladder-stepped a load from 5.4 to 5.8 gr with 220 gr SMKs and Rem 7-1/2 primers. COL was 2.20".

Results were terrible. Velocity ranged from low 700s to 875 fps or so, even within the same charge weights. Groups were about 2" at 50 yds. for any given load. Obviously too much space in the case to have consistent powder ignition.

N110 is my next experiment, though the closest source is an hour away so it might be a while before I make it up there.

ETA - I also chronyd the Hornady 110 gr VMAX Whisper load and it was puulling 2450 fps out of my 16" barrel. Plenty potent for hogs or deer.

I have got the best accuracy and lowest SD/ES with Vhit N-110.

Not the quietest as N-110 is on the slow side, but if the accuracy is there I am ok with it.

With an AR I use H-110 or N-110 as I wont be shooting it past 150 yards or so. The H-110 is a bit dirtier with or without a can.

Subsonic loads with H110 or N110 are not good for a semi 300 BLK.

Quote:

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Originally Posted by Todd.K

Subsonic loads with H110 or N110 are not good for a semi 300 BLK.

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That is why I have an M-16 RR.

Why are subs not good with H110 or N110?

Those powders don't generate enough gas pressure to cycle the action within Colt M4 specs for cyclic rate. This also applies to semi autos as cyclic rate and bolt velocity are related.

You can make those powders cycle by using an oversized gas port, but then you can't shoot supersonic ammo without exceeding M4 specs for the upper range of cyclic rate.

The solution is to build guns like AAC and Noveske, and use subsonic powders, like A1680 - or factory Remington subsonic ammo, which can cycle the action with a normal sized gas port.

So is AA-1680 the best powder to use for Subsonic loads I do plan to work up some sub loads to because a Can for my Blackout is on my to buy list in the future.

Ed

Have you had any trouble with the magazines?

I think A1680 is the best powder for subsonic from an AR if the primary goal is reliable function. RE-7 can work also but the charges are rather compressed.

I am going o pick up some 1680 but good to know the RE-7 can also work I have that already I use it for my 6.8. How much RE-7 do I use to keep it in the subsonic range.

Ed

Quote:

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Originally Posted by rsilvers

I think A1680 is the best powder for subsonic from an AR if the primary goal is reliable function. RE-7 can work also but the charges are rather compressed.

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I have only shot about 30 rounds with mine up until now using a 30 round Pmag I only loaded 5 at a time never did try to pack it yet but it ran flawlessly.

Ed

Quote:

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Originally Posted by Logicalpath

Have you had any trouble with the magazines?

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You want to avoid a stuck bullet and pressure is not an issue, so start with 11 grains and work down to 1000 fps. 2.120 OAL for a Sierra 220.

Quote:

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Originally Posted by Todd.K

Subsonic loads with H110 or N110 are not good for a semi 300 BLK.

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I should say auto loading 300 BLK, they are fine in a bolt action.

A better subsonic load that cycles closer to the supersonic ammo is an often overlooked improvement of the 300 BLK.

OK went through some more loads today down at the Grove. Just doing hi and low of the 5 shot strings now. All groups 100 Yards all loads in LC brass with Tula 223 primers


178Gr Hornady Match AA1680 14.4 Grains 2.22 OAl could go hotter very consistent velocity's but not very accurate I was surprised 2" or bigger groups
SD 7.14
ES 18.39
AV 1736
HI 1743
LO 1725

110gr Barnes TTSX H110 19.4 Grains 2.05 OAL good velocity not supper accurate 1 1/2" groups nothing to brag about.
SD 14.01
ES 34.77
AV 2424
HI 2435
LO 2400

110gr Barnes TTSX H110 20 Grains 2.05 OAL groups opened up even more with this load I need to try a lighter load I think
SD 8.00
ES 19.58
AV 2463
HI 2474
LO 2455


110gr Hornady Vmax H110 20 Grains 2.05 OAL good groups almost 1MOA.
SD 10.04
ES 25.69
AV 2401
HI 2412
LO 2386

110gr Hornady Vmax H110 20.5 grains 2.05 OAL Best groups 5 shots all touching under 1" very pleased pressure signs were light this will be the load I use.
SD 6.63
ES 16.09
AV 2431
HI 2437
LO 2420

110gr Hornady Vmax H110 21 grains 2.05 OAL to much signs of pressure but she was fast but groups did open up as well as to hot of a load.
SD 17.74
ES 45.74
AV 2501
HI 2517
LO 2471


__________________
Ed

NRA Member
Utah CCW Holder
MD Designated Collector
Gun Fanatic

Here are some more from earlier in the week Same thing LC brass Tula .223 primers 16" Wilson Combat barrel groups at 100 yards.

165gr Speer SPBT H110 16 grains 2.15 OAL shot OK 1 1/2-2" groups no signs of high pressure.
SD 6.16
ES 17.19
AV 1827
HI 1835
LO 1817



125gs Nosler BTBT H110 18.6 grains 2.13 OAL showed minimal pressure signs nothing that worried me shot very well 4 out the 5 touching ever group always had one a Little outside could be me and my 7 power scope but group were under 1 1/2" every time
SD 13.11
ES 39.47
AV 2197
HI 2216
LO 2177

150gr Nosler BTBT H110 16.7 2.13 OAL no pressure signs grouped OK nothing to brag about 125gr are much better in my rifle. If i could get 2000fps with the 150 and tighten the groups just a bit I think it would be a good deer round.
SD 10.19
ES 28.89
AV 1945
HI 1953
LO 1924


__________________
Ed

NRA Member
Utah CCW Holder
MD Designated Collector
Gun Fanatic

The 125gr NBT doesn't come apart much, the 150gr may not upset at all at the lower velocity.

The slower speeds in the 300 BLK means you can use bullet weights that would be considered varmint weight in a 308/30-06, and they will hold together and penetrate enough.

What is a good bullet for the Blackout I wanted to go with a 125 or 130 grain bullet if I could.

Ed

Quote:

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Originally Posted by Todd.K

The 125gr NBT doesn't come apart much, the 150gr may not upset at all at the lower velocity.

The slower speeds in the 300 BLK means you can use bullet weights that would be considered varmint weight in a 308/30-06, and they will hold together and penetrate enough.

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Back in the mid 1990's I was working with a small sako action and the 7.62 x 39 cartridge built by Bill Wiseman for me. Before taking it on a mountain lion hunt I decided to try it on a deer for terminal effectiveness. My muzzle velocity was in the 2225 ft/sec range and the impact distance was approximately 100 yards. The bullet performed like a controled expansion soft, held together very well. I would think them excellent for pigs. The mountain lion also suffered the fate of the BT.

http://i181.photobucket.com/albums/x...o/DSCN0124.jpg

http://i181.photobucket.com/albums/x...o/DSCN1410.jpg

I am loading 125 grain Sierra Pro Hunters now and am getting 2300fps out of them I will be using them on deer this year.

Ed

That may be a little warm. 2250 fps is probably where I would stop. depending on your powder and OAL. The factory 125 grain ammo is about 2220 fps.

Quote:

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Originally Posted by rsilvers

That may be a little warm. 2250 fps is probably where I would stop. depending on your powder and OAL. The factory 125 grain ammo is about 2220 fps.

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Yes it is a little hot but I am loading them a little long as well. I am loading 20.5 grains H110 in LC Brass at 2.05 OAL (Not recommended always work your way up) 2307fps average hot yes but should be a good round for deer but I need to check expansion at 100 yards.

Ed

300aacblackout.com has gel tests of that. Just figure out at what range you will have the same velocity.

http://www.300aacblackout.com/resour...t06OCT2010.pdf

The gel test was at 2095 fps. So if you start at 2300 fps, then you will reach 2095 fps at 70 yards.

http://img713.imageshack.us/img713/8...wshot1copy.jpg

http://img707.imageshack.us/img707/2...wshot1copy.jpg

http://img854.imageshack.us/img854/3...cn0495copy.jpg

Quote:

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Originally Posted by rsilvers

I think A1680 is the best powder for subsonic from an AR if the primary goal is reliable function. RE-7 can work also but the charges are rather compressed.

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Lil'Gun has worked pretty well for me in both super and subsonic roles.

I have RE7 and IMR4198, but haven't bothered with them.

How much chamber pressure you figure is required to cycle the action?

About 25,000 psi - but only with slower powder like RE7, H4198, or A1680. If you make 25,000 psi with Bullseye pistol powder, it won't cycle.

Any opinion on handgun powders? I initially saw someone post that a .45 ACP load for 230g FMJ would be about subsonic.

Never tried it, maybe I oughta. You figure it won't cycle?

45 Auto has a different bore dimension and case capacity so it is not comparable.

You want a burning rate and bulk density around RE7, A1680, or H4198.

http://www.reloadbench.com/burn.html

Todd.K
I beg to difer with you. My Speer Hotcor 150 gr BT opened up very nicely all the way out to 200 yards. All the bullets I found were very nice mushrooms. :D So out to 200 yards they should work very well on pigs and deer. If you need more distance then the 130 gr Speer HP's should do well out to 250 yards.

I was out test firing an AR yesterday afternoon at the public range. There was some cat shooting a non-NFA 300blk with a loud brake.

This guy was a strange BLK boy. He left his brass there... which I took for a member here who's shooting this caliber....

But when I asked him about going shorty, silenced, sub sonic, etc.... He was like... "that's too much paper work".

Struck me that he's missing any upside to the round by just shooting a full sized gun. :confused: AND not loading the round or saving his brass.

300 BLK is simply a 30 caliber AR15. So when I hear that, it sounds like anyone shooting a 30-30 or 7.62z39mm needs to have a short barrel and a suppressor.

Quote:

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Originally Posted by markm

I was out test firing an AR yesterday afternoon at the public range. There was some cat shooting a non-NFA 300blk with a loud brake.

This guy was a strange BLK boy. He left his brass there... which I took for a member here who's shooting this caliber....

But when I asked him about going shorty, silenced, sub sonic, etc.... He was like... "that's too much paper work".

Struck me that he's missing any upside to the round by just shooting a full sized gun. :confused: AND not loading the round or saving his brass.

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Newbie with money to burn? NFA. Is a PITA, but it's the only game in town.

Quote:

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Originally Posted by Maryland_Shooter

Newbie with money to burn? NFA. Is a PITA, but it's the only game in town.

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I couldn't even fathom the notion that he was leaving the brass. Sometimes I'll ask for brass from people shooting .223 who look like they don't care about the brass... but a caliber like this?

The guy I build a 300 BLK upper for loads the ammo, so someone will get to use it.

Quote:

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Originally Posted by GunnutAF

Todd.K
I beg to difer with you. My Speer Hotcor 150 gr BT opened up very nicely all the way out to 200 yards.

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I was talking specifically about the Nosler Ballistic Tip.

http://www.300aacblackout.com/resour...t06OCT2010.pdf
The 125 NBT was the toughest of the 125gr and 130gr tested, showing the least upset and deepest penetration. The 150gr NBT would probably upset less, or with a low enough velocity not at all.

I also see no good reason to use any 150gr for deer with the results of the lighter bullets.

Todd.K
That why I choose the Speer bullets- thinner jacket. I stopped using them in my '06 cause of that. Moved up to 180 gr Speers/SEI to stop blow ups! The NBT's are a thicker jacket though not the 125gr they are a varmit bullet in the '06. I going have try a find some of those 125 gr SEI's :D