Which powder to use?

[Nick Danger]

Im looking at 190 gr subsonic loads for 300 blkout on hodgdon site. I notice powder loads are almost the same and the presssure for three different powders are like 18K, 22k and 23k in PSI. So if you have all three powders which would you choose?

Twist: 1:8.000"
Barrel Length: 16.000"
Trim Length: 1.363"
BULLET WEIGHT
190 GR. HDY SUB-X
CASE
HORNADY
PRIMER
REMINGTON 7 1/2, SMALL RIFLE MAGNUM

	Starting Load		Maximum Loads
	Manufacturer	Powder		Bullet Diam.	C.O.L		Grs.	Vel. (ft/s)	Pressure		Grs.	Vel. (ft/s)	Pressure
	Hodgdon	CFE BLK	BUY NOW	0.308"	2.050"			null			12.3	1,062	18,700 PSI
	Hodgdon	Lil'Gun	BUY NOW	0.308"	2.050"			null			8.3	1,044	23,100 PSI
	IMR	IMR 4198	BUY NOW	0.308"	2.050"			null			11.4C	1,032	22,800 PSI

 

[spife7980]

Not sure what the mystery powders in question are and I’m not gonna bother searching but try cfe blk. It’s even in the name. For subs I’d start at 10 and work up to 12, you’ll probably find the sweet spot right when the powder fills enough to just touch the bullet when seated, likely more towards 12 than not. But start low and work up.

 

[Nick Danger]

Not sure what the mystery powders in question are and I’m not gonna bother searching but try cfe blk. It’s even in the name. For subs I’d start at 10 and work up to 12, you’ll probably find the sweet spot right when the powder fills enough to just touch the bullet when seated, likely more towards 12 than not. But start low and work up.

Thx for the reply but... Im asking about the pressures? I guess im asking should I load to a lower PSI or the higher one?

 

[Gwak2006]

Is this for an AR?

 

[Nick Danger]

Is this for an AR?

yes 10.5" 1:8 barrel

 

[Gwak2006]

yes 10.5" 1:8 barrel

I would try the higher pressure to help reliability. Subs in short ARs can be a problem. Especially if you don't have a pistol length tube.

 

[spife7980]

Thx for the reply but... Im asking about the pressures? I guess im asking should I load to a lower PSI or the higher one?

Well that would depend entirely on the powder now wouldn’t it

 

[Nick Danger]

Not sure what the mystery powders in question are and I’m not gonna bother searching but try cfe blk. It’s even in the name. For subs I’d start at 10 and work up to 12, you’ll probably find the sweet spot right when the powder fills enough to just touch the bullet when seated, likely more towards 12 than not. But start low and work up.

I use CFE blk & 12.3 gr and I get about 1068fps.

 

[spife7980]

I use CFE blk & 12.3 gr and I get about 1068fps.

That’s right around perfect in my book, I landed in 12.1 with my preferred 220prohunter.

But in my addition to my comment pressure depending on a powder, it’s more burn rate dependent and especially platform dependent. Peaking at 18k with a pistol powder won’t work the bolt because it’s not enough residual, 18k peak with a slower burning cfeblk will have enough port pressure to cycle the thing, 18k with a slower still like h4350 won’t work the bolt again because it’ll be likely be impossible to get enough powder in the case. Many considerations in powder selection

 

[Shoots 700's]

Ive used 4198 with 220's and its very quiet, and runs unsurpressed and suppressed

 

[ARShooter91]

N120 works very well and N110 does as well if it cycles your gun. N110 is by far the most quiet powder I've used for 300blk

 

[GCBigTex]

I know that this does not answer your question, but I have tried CFE BLK and found it to be noisy (too much gas) in my AR platform vs factory Hornady 190 gr SubX ammo. I tried H110 and it was much quieter and produced plenty of gas to reliably cycle my 16" barrel gas gun.