The BlackOut was my first choice when I first got my hands on these rifles. The low velocity (1900fps) with 125 Nosler BT caused me to rethink that first impulse. I really think I can get a bit more out of it the barrel has 5R rifling so I think it could be pretty fast.
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Caliber Choice? Piston System...
- Thread starter CaptnC
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That's incredibly slow for a 125 out of a 16". I'm running the 150gd at 1875 out of a 7.5".
A good friend who has shot the BO for a while said the barrel length didn't really matter. He said you can't get much more velocity of the BlackOut . He told me up front it wouldn't really gain much with the longer barrel. He too shoots a 7.5 barrel.
What powder are you using?
What powder are you using?
You'll gain anywhere from 125 - 200fps going from 7.5 to 16. I'm running CFE BLK. The bullet is only seated about half way down the neck, but I'm crimping with a Lee fcd and haven't had an issue. There's a few others running around this load. Obviously start low and work up if you try it!
Edit: that was shot with irons at 50m
CaptnC, if you read your own posts, you've already made your mind up on the 7.62X39mm and...that's fine! Honestly, the ballistic 'difference' between it and the .300 BLK is nothing. They are 'the same' for all intents and purposes. If you already have the dies and WANT the 7.62X39, then go for it. Done. Moving on...
What you don't seem to want to hear is what so many are telling you - DON'T SCRAP THE .300 BLK. It is the 'better' option all around. Better bullet selection. A .308" bore firing .308" bullets. The ability to go sub-sonic in the future, if you decide to play in that sandbox. Brass is easy to make from .223/5.56 which is always laying on the ground at my local gun range. It is 'cheap' to load as it doesn't use much powder. Mags are the same as .223, so those are everywhere. Bolt head is the same as for .223, so that's nice should parts become an issue when we get our next Dem president and people go into panic buying mode again. This round is VERSATILE, and SIMPLE with lots of components to pick from.
Revisiting the 7.62X39mm. It takes a different magazine than 'normal'. It uses a different bolt head. It's bore can be anything from .308" to .312" and anything between those two. That's why 7.62X39mm dies usually have two different sized expander balls (.308" and .311") What bullets to use? What about pressure when running a .311" bullet down a .308" bore? It WILL go up. How much is a matter of testing and none of us has a piezoelectric transducer attached to our barrels to really measure it. Just because the gun didn't come apart doesn't mean it 'liked' it. Accuracy - generally the .300 BLK will be more accurate, but that's more a matter of finding the right load for your gun, which is easier when the bore is .308" and the bullets are .308". Obviously a good, accurate load can be found for a 7.62x39mm but it might take more work. On the plus side, you can buy super cheap, steel cased 7.62X39 ammo to just blast away with when you want to get your Rambo-freak on. That's fun! There is no 'cheap', comparable .300BLK ammo out there
The 6.8 SPC guns can be made into a Spec II guns, which is better from a reloading standpoint, but who cares? You are already geared up for the 6.5 Grendel and the 6.8 SPC isn't going to give you anything you don't already have. Maybe make those into 6.5 Grendels since you already like that round and are geared up to load for it.
You are going to go with the 7.62X39mm. Your posts already point that direction. Awesome! Just go into it eyes wide open and realize that the .300BLK you have that is already shooting great would be 'just as good' and perhaps easier/better in the long run (reloading components, mags, bolt heads, brass, sub-sonic capability 'built-in', just being some of the pros over the Russian round.) Since you reload, you are golden either way. But I wouldn't let the $30 cost for some LEE dies prevent me from keeping the .300BLK around to play with and experiment on. What's it hurt to keep that gun 'as is', keep the 7.62X39mm you have 'as is' and just tinker with the 6.8 SPC guns since they don't seem to be shooting worth a dang anyway?
It's your circus and your clowns so you can run the big top as you see fit. Keep us posted on what you decide to do.
What you don't seem to want to hear is what so many are telling you - DON'T SCRAP THE .300 BLK. It is the 'better' option all around. Better bullet selection. A .308" bore firing .308" bullets. The ability to go sub-sonic in the future, if you decide to play in that sandbox. Brass is easy to make from .223/5.56 which is always laying on the ground at my local gun range. It is 'cheap' to load as it doesn't use much powder. Mags are the same as .223, so those are everywhere. Bolt head is the same as for .223, so that's nice should parts become an issue when we get our next Dem president and people go into panic buying mode again. This round is VERSATILE, and SIMPLE with lots of components to pick from.
Revisiting the 7.62X39mm. It takes a different magazine than 'normal'. It uses a different bolt head. It's bore can be anything from .308" to .312" and anything between those two. That's why 7.62X39mm dies usually have two different sized expander balls (.308" and .311") What bullets to use? What about pressure when running a .311" bullet down a .308" bore? It WILL go up. How much is a matter of testing and none of us has a piezoelectric transducer attached to our barrels to really measure it. Just because the gun didn't come apart doesn't mean it 'liked' it. Accuracy - generally the .300 BLK will be more accurate, but that's more a matter of finding the right load for your gun, which is easier when the bore is .308" and the bullets are .308". Obviously a good, accurate load can be found for a 7.62x39mm but it might take more work. On the plus side, you can buy super cheap, steel cased 7.62X39 ammo to just blast away with when you want to get your Rambo-freak on. That's fun! There is no 'cheap', comparable .300BLK ammo out there
The 6.8 SPC guns can be made into a Spec II guns, which is better from a reloading standpoint, but who cares? You are already geared up for the 6.5 Grendel and the 6.8 SPC isn't going to give you anything you don't already have. Maybe make those into 6.5 Grendels since you already like that round and are geared up to load for it.
You are going to go with the 7.62X39mm. Your posts already point that direction. Awesome! Just go into it eyes wide open and realize that the .300BLK you have that is already shooting great would be 'just as good' and perhaps easier/better in the long run (reloading components, mags, bolt heads, brass, sub-sonic capability 'built-in', just being some of the pros over the Russian round.) Since you reload, you are golden either way. But I wouldn't let the $30 cost for some LEE dies prevent me from keeping the .300BLK around to play with and experiment on. What's it hurt to keep that gun 'as is', keep the 7.62X39mm you have 'as is' and just tinker with the 6.8 SPC guns since they don't seem to be shooting worth a dang anyway?
It's your circus and your clowns so you can run the big top as you see fit.
Keep us posted on what you decide to do.CaptnC, if you read your own posts, you've already made your mind up on the 7.62X39mm and...that's fine! Honestly, the ballistic 'difference' between it and the .300 BLK is nothing. They are 'the same' for all intents and purposes. If you already have the dies and WANT the 7.62X39, then go for it. Done. Moving on...
It's your circus and your clowns so you can run the big top as you see fit.
Sir you seen right through me! I know I have a strong bias towards the 7.62x39!
And that girls and boys is why I posted the thread. I'm hard headed as hell (as many here have seen, my EABCO 6.5x284 thread is a prime example). Because of that known element I wanted to seek the advice of those who know the benifits of the "other" cartridges.
I'm like MudRunner, 6.5 Grendel to my core. I have already been digging around looking for a 16" SS heavy profile carbine length gas system before I even started this thread.
I've had 7.62x39 AR's in the past still do. But it lacks the thump at longer range that I had been waiting from the AR platform. Then the Grendel comes along and I scrap almost all of my 5.56 rifles to convert them into Grendel's. I even scrapped a 7.62x39, but ended up buying the parts to build it back again.
Then this deal comes along an throws a monkey wrench into.my world. I don't care too much for the ballistics of it so far, but the accuracy has my attention! The 6.8 will most likely ride the bench for a while. The 6.8 with the piston may be turned into a 6.5 Grendel. I have two more 6.8's so is not totally over for that round.
But thank you sir for keeping honest! The hunt next week will be done with the 7.62x39, but I believe the Osprey 300BO will wear the can this fall once I get just a bit more HP out of it!
I will post the load from the 6.8 tomorrow...I want to say the powder was 2200...27.5gr of it. The velocity was knocking on the door of 2700fps with 110 VMax....IIRC
Keep it coming guys!
I'm only hard headed...not brain dead!
Well, I bought the 300AAA BlackOut dies and CFE-BLK today. So I will be giving it a go to see if I can hit at least 2200fps with a 125gr HPM or the 110 VMax..
We shall see if it can bump the 7.62x39 out of my favor! LOL
I'm interested to hear about your results. Should be about 'equal' - ballistically speaking - to the 7.62X39mm but with fewer quirks to deal with over the long term (i.e., bullets and barrel .308", mags same as .223, bolt head same as .223, and more subsonic options if/when you get around to trying that out with your suppressor.) ARs are fun and playing around with new cartridges is enjoyable, too.
It looks like you SHOULD be able to get a 125 gr bullet to 2,200fps (per the Nosler data) but you'll need 300-MP powder to do it
With the CFE BLK powder, you will easily get above 2,200fps with the 110gr bullet.
It looks like you SHOULD be able to get a 125 gr bullet to 2,200fps (per the Nosler data) but you'll need 300-MP powder to do it
With the CFE BLK powder, you will easily get above 2,200fps with the 110gr bullet.
I agree it has quite a few pros over the cons of the 7.62x39.
Brass is the first thing that comes to mind. I find buckets of BlackOut brass when at the range. My buddy got tired of me bringing it to him.
Bullets is another. Won't have to deal with the .310 bullets. Although I do have some 308 bullets loaded up in my 7.62x39 for testing at 200yds to see if they stabilize.
So I will report back after the next range trip.
Brass is the first thing that comes to mind. I find buckets of BlackOut brass when at the range. My buddy got tired of me bringing it to him.
Bullets is another. Won't have to deal with the .310 bullets. Although I do have some 308 bullets loaded up in my 7.62x39 for testing at 200yds to see if they stabilize.
So I will report back after the next range trip.
I'm curious to hear if your .308" bullets stabilize in your 7.62X39mm. I think it was Sierra that tried some .311" through a .308" bore in .7.62X39mm just to see what would happen (pressure and accuracy) and apparently it wasn't the dumpster fire one might imagine. The effects are all theoretical until someone with the equipment tests it out. Wish I could find a write up with their actual results. It would be a good read.
Still, best to stick with correct bullet size for bore size and that dang 7.62X39 has been made in a lot of different bore sizes making it 'interesting'. The .300BLK simplifies all those issues nicely.
Still, best to stick with correct bullet size for bore size and that dang 7.62X39 has been made in a lot of different bore sizes making it 'interesting'. The .300BLK simplifies all those issues nicely.
If you're set on 110-125gr then H110/w296, or lil gun will get you higher velocities. Just can't cram enough CFE BLK in the case.
cohunt
Well-Known Member
I get 2200 with the tac TX bullet using h110 in my 8.5" barrel, Iirc guys are getting around 2400 with 16" barrels
Well...hell...wish I had known this yesterday when I went to the store.
I recently ran out of my top three powders RL-26, 4831SC and Benchmark. So I ran to one of the main gun stores in Houston. They happen to have everything I was looking for, plus they had the CFE BLK. I bet they would have had H110 too. I think I see that one kind of regularly at the smaller stores I visit.
I also have a bunch of Sierra 155 Palma HP bullets. Would the CFE BLK be ok for the larger bullets?
Frog, I had some guys report the 308 bullet shot great at 50yds, but group size opened up quickly. I assume it's because there was not enough bite in the lands so the bullet lost stability, then kind of knuckle balled at longer range.
I recently ran out of my top three powders RL-26, 4831SC and Benchmark. So I ran to one of the main gun stores in Houston. They happen to have everything I was looking for, plus they had the CFE BLK. I bet they would have had H110 too. I think I see that one kind of regularly at the smaller stores I visit.
I also have a bunch of Sierra 155 Palma HP bullets. Would the CFE BLK be ok for the larger bullets?
Frog, I had some guys report the 308 bullet shot great at 50yds, but group size opened up quickly. I assume it's because there was not enough bite in the lands so the bullet lost stability, then kind of knuckle balled at longer range.
H110 and W296 are the same powder, and pretty popular. It's magnum pistol powder.
