Upper question 300 BO

SDIVER2006

SDIVER2006
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So I’m looking at getting a 300 BO upper, so a few questions

1) Are the PSA ones any good?
2) what’s the Recoil? For the wife
3)What’s the better length between 7-10 inches

Used for Range toy, and for the house..

As always thanks guys
 
I have a PSA ar15 and KS47 both work fine. I do not have experience with their 300 stuff but I am sure they are fine.
I have a 300 aac I assembled, I used a 7 inch BA barrel.
Recoil is very light when shooting subs, have not yet run supersonics but will in about an hour or so.
Mine is targeted for home defense.
p9TPyTkl.jpg
 
I’m no expert but I have a couple 300’s and did a good amount of research/reading beforehand.

Many report the PSA uppers are perfectly fine. I opted to stay away from them because they only offered 1/8, not 1/7 twist, and knowing that the Honey Badger was made with a 1/5 to ensure those heavy subs stabilize, I opted for 1/7 as a min.

Recoil doesn’t feel much different to me, if anything it’s a little less snappy, comparing 55gr .223 vs 125gr 300BLK supers.

I found that the Aero/BA 8” barrels shoot great and function everything from 110-220gr suppresses and unsuppressed, so I’ve become a little biased. I have 2 of them now.

B6E49BCB-7342-4A7B-8F65-44BA433D50CA.jpeg
 
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If you’re close to Charlotte (not sure what part of Pineland you’re in), you could borrow two of mine and see.

I have a 10” KAC upper with a Noveske barrel (1:8), and a 7.5” (1:7) PSA complete upper. The 7.5 was recently purchased from the BST here and I’ve yet to shoot it.
 
I bought a PSA 8.5" 300BO about a year ago and it's a lot of fun. It's a 7 twist barrel and they offer a lot in 7 twist. I have shot subsonics and supersonics through it and have used a flash can and a suppressor. Recoil isn't bad at all. My wife uses it. I also use it for range fun and the house. It wears a light on it now as well. I plan to buy another soon.

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@Michael458 has more info on this than you want to read! He did all the pressure and ballistic work on these and came to the conclusion that 10 inches was the cat's meow. He built me a PSA 10 incher and says he will give me ammo for life. That was a year ago, so far I still have the first 100 loaded in mags and stacked by my bed. He has killed Several foxes with his.
 
@Michael458 has more info on this than you want to read! He did all the pressure and ballistic work on these and came to the conclusion that 10 inches was the cat's meow. He built me a PSA 10 incher and says he will give me ammo for life. That was a year ago, so far I still have the first 100 loaded in mags and stacked by my bed. He has killed Several foxes with his.

#jealous


Sent from my iPhone using Tapatalk
 

I've had one of the DSG/Seekins 'Black Friday' uppers since the original run of 'em back when. Makes a damn nice little gun. With 120gr supers, it'll easily ring a 8" gong at 100yds with just a cheap RDS.

Fixin' to re-barrel with a 1/7 twist, 8" BA in preparation for my Dead Air Sandman-K getting out of jail.
 
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I've had one of the DSG/Seekins 'Black Friday' uppers since the original run of 'em back when. Makes a damn nice little gun. With 120gr supers, it'll easily ring a 8" gong at 100yds with just a cheap RDS.

Fixin' to re-barrel with a 1/7 twist, 8" BA in preparation for my Dead Air Sandman-K getting out of jail.
I bought mine when they were selling what amounted to an SBR kit for like $500.
 
I have a 10" PSA upper and a 7.x " PSA upper , and they're all good. I shoot mine mostly suppressed and I love it. It's one of my favorite rifles to shoot!
 
Recoil is not a concern at all. I shoot NTCH & I can't tell any difference vs 5.56. Huge bonus to me is the greatly reduced muzzle blast vs 5.56.
 
I went 10.5” 2nd time around.

12.5” per Mr Guns and Gear seems to be the best length for 300blk. With supers, you gain a lot.
 
My PSA seems fine. Don't care for the handguard. Twist may be a little slow for the longest heaviest subs.

Went 10.5, for reasons I can't recall.

Oh I do think it is on the heavy side, barrel is fatter than it needs to be.
 
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I built 2 using PSA lowers. No problems. One is 16" and the other is 10.5".

Barrels brand are different in each gun.
 
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What twist do you think it would need?
No first hand knowledge just reading, some folks report instability with long bullets like the 240gr SMK in 1:8. Some say they shoot fine. 1:7 doesn't seem to have any debate.

I've only shot cast 230gr I researched the round a bit, bought the upper, then lost interest. When I get back to playing with it I foresee mostly supers. 1:8 has been fine, 1:10 might even be better. Depends on a person's plans.
 
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Was just asking as PSA makes 7 twist also. Seems like that is plenty fast for any bullet even subsonic. Don't know many using the 240s subsonic. Mostly the 220s.
 
For me, I’d immediately rule out the bottom one due to 1:8 twist.

With the top one, the rail is longer than the barrel. That’s fine if you always intend to run the flash can. But if you wanted to run a silencer, there aren’t really any choices for 300BLK that fit inside of the PSA lightweight M-Lok rails, even though it’s only going in <1”. Even most other muzzle devices (flash hiders or brakes) will leave ports inside the rail and potentially damage it.

So if you ever plan on running it in another configuration that it comes, you need the second one...or just know you’ll be changing handguards.
 
Ive built several 300 BO's over the years as short as 6.5" and as long as 16" . Put THOUSANDS of rounds down rage with them and converted thousands of 5.56 rounds to 300 BO myself. They are generally lighter recoiling than .223 and out to a couple of hundred yards are as accurate in the supersonic loadings. Also they arent very finicky about barrel length and functioning. Having said all that I have to say my way over the top favorite 300 BO upper is the SIG Rattler top end on a standard AR lower. You see the entire kit with 5.5" barrel as cheap as $1200 sometimes which comes with everything but a semi stripped lower.. Add a stock or brace and your'e in business.

Heres mine of a SIG SBR'd M400 lower but you can use ANY standard patter lower.

jRneTa.jpg


oWquEy.jpg
 
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Ive built several 300 BO's over the years as short as 6.5" and as long as 16" . Put THOUSANDS of rounds down rage with them and converted thousands of 5.56 rounds to 300 BO myself. They are generally lighter recoiling than .223 and out to a couple of hundred yards are as accurate in the supersonic loadings. Also they arent very finicky about barrel length and functioning. Having said all that I have to say my way over the top favorite 300 BO upper is the SIG Rattler top end on a standard AR lower. You see the entire kit with 5.5" barrel as cheap as $1200 sometimes which comes with everything but a semi stripped lower.. Add a stock or brace and your'e in business.

Heres mine of a SIG SBR'd M400 lower but you can use ANY standard patter lower.

jRneTa.jpg


oWquEy.jpg
Is there a suppressor that will work well and for a significant amount of time with a barrel that short?
 
Is there a suppressor that will work well and for a significant amount of time with a barrel that short?
Sure. Its a much lower pressure round than a 5.56 . Ive been shooting supersonic 300 BO for years with 6.5" barrels through a SIG 7.62 Ti and a silencerco specwar. No issues. The 5.5" Ive shot thousands of rounds of subs and supers through the 7.62 Ti with no signs of erosion.

XialVT.jpg
 
I've got a 8.5 PSA 1/7 twist upper and it just works. It's my wife's favorite AR and one of mine as well. Recoil is minimum with an H buffer.
 
Two Black Friday's ago I picked up the PSA 8.5" Pistol Length Nitride 300 AAC 1/7 2A Armament Keymod Upper to go on an Anderson lower with a CMC trigger, LAW folder and a KAK brace. Without the folder it was a $400 build including the dot. It'll fit in a laptop bag and can be carried as a concealed pistol.
If the KAK brace happens to come back and hit your shoulder, it's not as comfortable as the SBA3 it now sports.300P.c.jpg 300Pfc.jpg

This is a 10"SBR used for hunting and HD, expensive build, and a shooter :D 300BLKc.jpg

So far they've both been reliable. I did add a piece of fuzzy velcro on the brass deflector to lessen the case mouth deformation upon extraction.

*edit* These threads should merge- https://www.carolinafirearmsforum.com/index.php?threads/adding-a-300blk.49036/#post-982974
 
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Is there a suppressor that will work well and for a significant amount of time with a barrel that short?
There are a handful warrantied with no barrel length restrictions.
 
Two Black Friday's ago I picked up the PSA 8.5" Pistol Length Nitride 300 AAC 1/7 2A Armament Keymod Upper to go on an Anderson lower with a CMC trigger, LAW folder and a KAK brace. Without the folder it was a $400 build including the dot. It'll fit in a laptop bag and can be carried as a concealed pistol.
If the KAK brace happens to come back and hit your shoulder, it's not as comfortable as the SBA3 it now sports.View attachment 184755 View attachment 184756

This is a 10"SBR used for hunting and HD, expensive build, and a shooter :D View attachment 184757

So far they've both been reliable. I did add a piece of fuzzy velcro on the brass deflector to lessen the case mouth deformation upon extraction.

*edit* These threads should merge- https://www.carolinafirearmsforum.com/index.php?threads/adding-a-300blk.49036/#post-982974
What went into that hunting/HD build?
 
Sure. Its a much lower pressure round than a 5.56 . Ive been shooting supersonic 300 BO for years with 6.5" barrels through a SIG 7.62 Ti and a silencerco specwar. No issues. The 5.5" Ive shot thousands of rounds of subs and supers through the 7.62 Ti with no signs of erosion.

XialVT.jpg
What would you consider the effective range of supers and subs out of that 5.5" barrel?
 
What went into that hunting/HD build?
10” McGowen SS hand lapped dual fluted bead blasted barrel, Syrac adj block, Seekins 10” guard, Hogan billet ambidextrous lower, Geisssele SSA-E trigger, WMD NiB black Cerakoted upper, WMD NiB BCG, Magpul grip, MFT Minimalist stock, Aimpoint T2, TBAC Ultra7 can mounted on flash suppressor.
End w/o can:
IMG_1972.JPG
 
What would you consider the effective range of supers and subs out of that 5.5" barrel?


100 yards with subs and 250 with super. The Rattler will cycle on just about anything but like most 300 BO you want a fast burning powder. Lets be honest , if you are shooting 300 BO with factory loads you are making a mistake. 1680 and H110 will do just about everything you need in a 300 BO and you are going to tailor your subs to run a thousand fps no matter the barrel length and 125 to a150 supers easily hit 2500 ish fps without overpressure even from a 5.5" barrel.
 
100 yards with subs and 250 with super. The Rattler will cycle on just about anything but like most 300 BO you want a fast burning powder. Lets be honest , if you are shooting 300 BO with factory loads you are making a mistake. 1680 and H110 will do just about everything you need in a 300 BO and you are going to tailor your subs to run a thousand fps no matter the barrel length and 125 to a150 supers easily hit 2500 ish fps without overpressure even from a 5.5" barrel.
Hang on, are you saying if I get a 300 BO, I have to start reloading?! ;)
 
OK 60 cents a round. Still 5x what you can reasonably do hand loading meaning you can shoot 5 times as much . You can pick up 500 rounds in the $280 to $300 range or you can load up a few thousand rounds for the same money. Pays for itself pretty quick.

300BO shines in its ability to run subsonic. You can tailor up some pretty impressive 220-240 grain loads that hit hard at 1000 FPS.
 
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