Page 1 of 1

300 BLK load development.

Posted: Mon Jun 17, 2013 3:42 am
by Aussie contractor
Probably of limited use unless you have a 300 Blackout and are developing subsonic loads, but I thought I would post the load data for you. The numbers after the projectile are the FPS readings from an F1 Chrony.
9.0gr AR2205, 208GR AMAX 1288, 1306, 1307, 1276
7.4gr Trail Boss (compressed) 208 GR AMAX 899, 957 (Third failed to chamber due to powder in the neck)
7.0gr Trail Boss (compressed) 208 GR AMAX 810, 859, 771.
6.4gr Trail Boss 208 Gr AMAX 705, 669, 772.
5.8gr Trial Boss 208 GR AMAX 530, 610, 435.
6.4gr Trail Boss 125 GR SAKO 1003, 1000, 951.
6.4gr Trail Boss 165 GR Lead with Gas check 1074, 1079, 1062, 1093, 1080, 1063.
6.4gr Trail Boss 175GR Lapua 818, 850, 921.

The learnings:

Trail Boss is OK with lighter projectiles in the 300 BLK. The larger projectiles need to seat too deep to use Trail Boss effectively - its just too bulky for the .300BLK. It is however a good choice for the .308win.
AR2205 at 9.0 GR throws them too fast to be subsonic. Its a tougher job to get the heavier pills to fly subsonic consistently. Lead gas check bullets are much more slippery than jacketed projectiles.

The next series of tests will be AR2205 in .3gr reductions. And AS30N starting at 6.0gr and working up in .2 gr increments.

Re: 300 BLK load development.

Posted: Mon Jun 17, 2013 3:45 am
by Aussie contractor
Oh - Rifle is a Remington 700 with factory 16.5 inch threaded barrel.

Re: 300 BLK load development.

Posted: Mon Jun 17, 2013 5:26 pm
by Dr.K
I guess my load development is slightly different than some.

I use the balance to make sure I have a good starting charge, then load a few, shoot, adjust the powder bar load a few, shoot, until I reach the desired velocity, then load'em up in bulk.

I only use the balance again, to make sure I'm not going over max charge weight, but for subs usually I'm nowhere close, so I don't have as much to offer based on charge weight.

Re: 300 BLK load development.

Posted: Fri Jun 21, 2013 3:09 am
by Homer
G'Day Fella's,

Aussie Contractor, thanks for that load data and nice to catch up for a phone chat yesterday!
There have been a lot of the factory Rem 700's sold in this chambering, and I assume for use with Sub-Sonic loads!!!

Doh!
Homer

Re: 300 BLK load development.

Posted: Sat Jun 29, 2013 8:57 pm
by Aussie contractor
OK Good news. All speeds in FPS, all projectiles 208Gr A-Max with moderator fitted. Remington 700 1:7 with 16.5 inch Barrel.
I can present the following results.
8.0Gr AR2207 - Projectile stuck in bore - No good!
8.8Gr AR2207 395FPS, Stuck in bore - no good.
8.0Gr AR2205 634, 719, 778, 865, 685 (too slow for consistency)
5.0Gr AS30N 721, 751, 796, 660, 807.
6.0Gr AS30N 959, 1039. 1015, 981, 1004.

The 6.0Gr AS30N was far quieter than the 8.0Gr 2205, despite the higher velocity. I suspect that is because all the powder is burnt before the projectile exits the barrel with the AS30N?

Now will they cycle the Mini 14?

Re: 300 BLK load development.

Posted: Sun Jun 30, 2013 9:03 pm
by emrisg
Try some accurate #5. 7 grains should get you 1025 with 208 amax and 16.5 barrel ( with suppressor). I have found the faster the powder the quieter the gun is.

Re: 300 BLK load development.

Posted: Mon Jul 01, 2013 5:09 am
by Aussie contractor
emrisg wrote:Try some accurate #5. 7 grains should get you 1025 with 208 amax and 16.5 barrel ( with suppressor). I have found the faster the powder the quieter the gun is.
Thank you - I am inclined to agree RE Powder speed. The AR2207 only produced 395FPS but was noisy! AA5 is an AS50N equivalent http://www.adi-powders.com.au/handloade ... alents.asp the AS30N is a red dot equivalent - so even faster. In Australia I am developing these loads just based on what I can learn from your guys. Thanks.

Re: 300 BLK load development.

Posted: Fri Jul 05, 2013 4:07 am
by Aussie contractor
Image

This is rifle I have been developing loads for.

Re: 300 BLK load development.

Posted: Fri Jul 05, 2013 11:17 pm
by paper9
300 BLACKOUT
POWDER /GRAIN/BULLET/GRAIN/DESCRIPTION/LENGTH/AVERAGE/MAX/MIN/PRIMER/OAL /CHRONOGRAPH

TRAIL BOSS/4.6/ HORN SP/110 /SP FB #3010 /16 INCH/1039 /1077/ 1000/REM 7.5/2.045/MAGNETO

TRAIL BOSS/5.5/HORN VMAX/110/ORANGE TIP #23010/16 INCH/1123/1191/1032/REM 7.5/2.045/MAGNETO

A1680/10.7/SIERRA MK/200/HPBT/16 INCH/1075/1097/1055/REM 7.5/2.20/MAGNETO

A1680/10.7/HORN AMAX/208/ORANGE TIP/16 INCH/1119/1153/1067/REM 7.5/2.1834/MAGNETO

Re: 300 BLK load development.

Posted: Sun Jul 07, 2013 5:00 pm
by bts0irv
8" Noveske gun with pistol gas, Yankee Hill suppressor
8.5 grains of H110 behind a cast lee 230 grain bullet with blue angel lube
lake city reformed brass, Federal primers.
Ejects all and bolt holds open. Very quiet.

Re: 300 BLK load development.

Posted: Wed Jul 10, 2013 8:46 pm
by grrifles
I have not shot for accuracy yet.

110 hor SP with 5 grains of trail boss for 1040 fps
245 cast with 3.5 grains of N 310 for about 750 FPS extremely quiet

Remington 700 16.5 barrel

Re: 300 BLK load development.

Posted: Tue Jul 16, 2013 4:26 am
by Aussie contractor
Thanks Guys. I will look for equivalents and try them. I am realising that accuracy and flat trajectory are important because even throwing the 208GR at 1030FPS you still need to hit vitals to stop anything. So weight of 125gr or 220gr are not THAT important when you need a head or heart/lung shot to kill. I have been shooting roo's on tags for while and unless you hit something that stops blood pressure or the brain, they just keep running.

Re: 300 BLK load development.

Posted: Tue Jul 16, 2013 7:07 am
by Homer
G'Day Fella's,

Aussie Contractor, that's an impressive looking set up you have there!
Especially that compact looking "Can" on the end of it!!!

So, I'd be interested to know how's the "Can" performing for you?

Doh!
Homer

Re: 300 BLK load development.

Posted: Tue Jul 16, 2013 7:09 am
by Aussie contractor
Homer wrote:G'Day Fella's,

Aussie Contractor, that's an impressive looking set up you have there!
Especially that compact looking "Can" on the end of it!!!

So, I'd be interested to know how's the "Can" performing for you?

Doh!
Homer
Homer, after using faster powders its FAR better than it was. Later in the month I hope to meet up with you and we can do some back to back testing?
The muffling effect is far better with faster powders.

Aussie.

Re: 300 BLK load development.

Posted: Wed Jul 17, 2013 2:10 am
by Homer
G'Day Fella's,

Aussie Contractor, good to hear it's doing what you want!

No probs, looking forward to an outing!
As mentioned before, I'm happy to have secure you gear here while your in town!!!

See you soon.

Regards
Homer