Best long range 300 Blackout load?

[Bug Splat]

Thanks a lot guys I'll start with some 155gr SMK and see how fast I can push them. My goal is to be +1100fps at 800 yards which I think is very possible if I can find the right powder that will end burn at 15-16 inches and still hit max pressure.

[Fjold]

At 1,000 feet of elevation and 72 degrees, JBM says that you need 2,300 fps at the muzzle to get 1102.9 fps at 800 yards.

The reputable sources like Hodgon says 2,100 fps second with a 135 grain bullet is a maximum load. It looks like you're trying to put an afterburner on a turtle.

[Bug Splat]

Most load data is going off 10" barrels not 16". Like I said I need to find a powder with the right burn rate for the bore size and length. I've pulled 300 more fps out of my 6.5-284 rifles, I can do the same with another round. Telling me it can't be done only makes me want it more.

[OIF0708]

Most load data is going off 10" barrels not 16". Like I said I need to find a powder with the right burn rate for the bore size and length. I've pulled 300 more fps out of my 6.5-284 rifles, I can do the same with another round. Telling me it can't be done only makes me want it more.

I like your attitude. I have been looking for similar information. I am just now getting into reloading, the 300 will be my first. Buying primed brass off gunbroker for the first run, save me from having to have "everything" to get started. I will measure all cases for length and weight then load with a hand held single loader. Looking for powder, bullet and oal measurements to help save on time and money also. I am not really looking for 800m, more along the lines of 200-250m. But any info/experiences I can take note of I will. Good luck and thanks for sharing.

[3006mv]

do you have a 1:8 twist? try 208 gr Amax or Barnes tsx 110 gr w/ N110 or 155 gr Lapua scenar.
you'll have to use quite a bit of holdover rise to get to your distances. Like 12' to 15' .

[Fjold]

Most load data is going off 10" barrels not 16". Like I said I need to find a powder with the right burn rate for the bore size and length. I've pulled 300 more fps out of my 6.5-284 rifles, I can do the same with another round. Telling me it can't be done only makes me want it more.

The load data from Hodgon is from the rifle data section.

You got a 300 fps loading your 6.5x284 hot which is about a 10% increase depending on bullet weight.

The 300 AAC maxes out at 2393 fps with a 115 grain bullet and 2127 fps with a 135 grain bullet. Extrapolating that ratio, it says that the 155 grain bullet will max out at 1861 fps.

Trying to get to 2300 fps means you have to load for a 439 fps increase. That's a 23.6% increase in velocity over maximum. Then you have to add in more powder because you're loading for a gas gun that bleeds pressure off to cycle the action.

Proportionally that would be like a 2800 fps, 142 grain load in your 6.5x284 being loaded up to 3,460 fps.

I say go for it! Load 25% over maximum, what can it hurt?

[6mmintl]

Good luck on your fantasy.

[FMJBT]

Nosler 125 BT loaded to around 2200 FPS should get out to around 550 yards before going subsonic. I haven't shot these yet to see how well they transition into subsonic, just a lot of number crunching in the ballistic calculator. Best bet would probably be to find something lightweight, around 110 grains with a pronounced boat tail to help it transition into subsonic without tumbling. I don't think you're going to find a load that will stay above 1100 FPS out to 800 yards, maybe 600-650. The key to getting further out will be finding a bullet that can transition well into subsonic. Either that, or get a scope with a ton of internal travel and launch big BTHP subsonic rounds like artillery shells.

[Whiterabbit]

Good luck getting anyone to comment on that one besides me. I wrote exactly that in post #15.

According to JBM, at 2500 ft elevation (typical shooting roundabouts me), a 180 grain sierra prohunter (prohunter = my standard for cheap jacketed) going 1050 fps (no transsonic region to contend with) can go to 1050 yards with 200 MOA of drop. 800 yards is 140 MOA of drop.

The vortex viper PST CQB scope with 1-4x mag (exactly what I would expect to find on any AR-type sporting arm) is cheap and has 220 MOA adjustment in the turret. Need more? There's 30 MOA in the reticle too.

250 MOA of adjustment gets you to 1250 yards.

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new bullet?

The 220 grain round nose has the same BC, no help there.

Lets go for the 240 SMK.

800 yards is 125 moa, 250 moa is close to 1400 yards. if you can see that far at 4x.

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Pretty sure for man sized targets this will pan out just fine.

[Whiterabbit]

aaaaaaaaaaand rereading your OP Bugsplat, I would give serious consideration to making your long range round and your subsonic round one and the same. Truly.

Having a tailored do-all im sure is nice, but having a do-all with ONE load is much nicer.

[klewan]

http://www.thebangswitch.com/1000-yard-shot-with-the-300-blackout/

Here's an article about a 1000 yard shot. He used PNW factory ammo, but you could try and emulate that with your reload.

[Ninety]

Wow the hate is high in this thread.

OP make sure you check back in with what you find..
I'm sure everyone has seen this .. but over 1000meters.. so man size target at 1000meters.. He is using a much shorter barrel though..

He's using 155 grain PNW supersonic at the long distance shot