300blk - Subsonic in Rattler "outperforms" BCM 9in

[Cool Breeze]

I don't know anything about ballistics so forgive me in advance. This just came out today. MAC suggests that subsonic will tumble out of the Rattler creating better terminal ballistics vs. zipping right through from the 9inch. No idea how watermelons stack up to ballistic gel or human tissue, but I was thinking about a Rattler or a 9inch AR pistol lately and I thought it might be interesting to discuss the ballistics of it all (subsonic and supersonic).

https://www.youtube.com/watch?v=rTxhMFqzqV0

[El Cid]

I don't know anything about ballistics so forgive me in advance. This just came out today. MAC suggests that subsonic will tumble out of the Rattler creating better terminal ballistics vs. zipping right through from the 9inch. No idea how watermelons stack up to ballistic gel or human tissue, but I was thinking about a Rattler or a 9inch AR pistol lately and I thought it might be interesting to discuss the ballistics of it all (subsonic and supersonic).

https://www.youtube.com/watch?v=rTxhMFqzqV0

I’ve only seen properly tested gel shots with the 110gr TTSX. But if SOCOM is fielding Rattlers... and they are buying the Winchester 190gr Sub-X... I think we can draw a correlation from that. I no longer have contacts in that arena to confirm anything though so that information is worth exactly what you paid for it.

[ccmdfd]

Sorry, but watermelons?

Really?

[flyrodr]

Sorry, but watermelons?

Really?

But bound to be certified genuine ordnance ballistic watermelon

[Xhado]

A non expanding 220 gr subsonic round will perform similarly to a pistol round.

It's not unexpected that it punches right through a melon.

[SecondsCount]

Sorry, but watermelons?

Really?

I stopped reading at the tumbling part.

[Grey]

Sorry, but watermelons?

Really?

Dude, human lungs are 83% water and watermelons are like 90% its a totally appropriate surrogate /sarcasm...

[Wondering Beard]

I’ve only seen properly tested gel shots with the 110gr TTSX. But if SOCOM is fielding Rattlers... and they are buying the Winchester 190gr Sub-X... I think we can draw a correlation from that. I no longer have contacts in that arena to confirm anything though so that information is worth exactly what you paid for it.

But could that correlation simply be that they have a niche use for it that is different than that of the rest of us civilians?

[Ndbbm]

But could that correlation simply be that they have a niche use for it that is different than that of the rest of us civilians?

Wouldn’t that niche use be quietly shooting unsuspecting combatants with a suppressed firearm.

Jason

[Wondering Beard]

Wouldn’t that niche use be quietly shooting unsuspecting combatants with a suppressed firearm.

Jason

I have no idea. I thought they went suppressed with pretty much everything in their inventory.

The only person I know here that has had operational experience with 300 BLK is Giving Back, but that may have been before the Rattler and the Hornady rounds got into their armory and, while he never went into much detail, he seemed to imply (if memory serves and I could be wrong) that it was an even more specific niche.

I imagine that Hornady's 190gr sub rounds do pretty well for their intended purpose; I've just never been really clear as to what that purpose was (excepting being really really quiet).

[ccmdfd]

I stopped reading at the tumbling part.

Smart move!

I should have done the same myself.

[RevolverRob]

We've talked before about how long, heavy, bullets at low velocity are more likely to yaw on impact. However, I've been led to believe and seen enough actual gel tests to conclude that yawing is not consistent unless high velocity bullets are specifically designed to do so.

I've read that the 220-grain Sierra Match King in .300BLK has been used 'operationally' (whatever that really means I do not know), but my understanding is, that it's use is primarily limited to things like sentry removal or other types of close-range covert work. Shot placement will emphasize immediate incapacitation (i.e., head shots). If you think about the roles that 147-grain subsonics from MP5-SDs were used for, that is now the realm of the .300BLK. I would figure the 220-grain SMK or the 190-grain Hornady Subsonic-X have superior terminal ballistics to a sub-sonic 9mm. However, for all intents and purposes sub-sonic .300BLK is just a big pistol round.

The advantage to a Rattler/other .300BO specific platform is the ease of suppression and the ability to swap to a far more effective loading when silence is no longer needed (i.e., the 110-grain Barnes loads) and gives you ~250-300y (maximum point blank) ability.

That Rattler is kind of a niche tool in many ways, but it is a much wider niche than pistols or SMGs. I'd rather carry a Rattler, MCX, adjustable gas-system equipped .300BO with a 10" barrel and a bunch of 110-grain bullets and a few mags of 190 or 220 subsonics than a rifle and SMG or rifle and suppressed pistol.

[El Cid]

But could that correlation simply be that they have a niche use for it that is different than that of the rest of us civilians?

First I’m in no way a tier 1 anything. But my understanding is the subs are used when quiet is key. Once it’s a fight and everyone knows you’re there, use the TTSX supers and your weapon is louder but more effective. I presume they want a sub round that’s got the best terminal ballistics a sub can offer for obvious reasons.

I have subs for my 300BLK but use them to show off how quiet the gun is to my friends and for steel matches. If I have to use subs to be extra quiet while shooting people CONUS, the world as we know it is no more. That’s the niche use they have in my opinion - they do things overseas that most of us will never know about. It’s one of those things that doesn’t really translate to most of us. Buy brand X rifle because it’s mil spec and passed the torture tests at SOCOM? Cool! It’s reasonable to say it will be a good choice for us stateside because it should easily hold up to our use. But if SOF personnel need subs to drop monsters... that does not mean any of us here need them. Use supers and drive on.

[Odin Bravo One]

I have no idea. I thought they went suppressed with pretty much everything in their inventory.

The only person I know here that has had operational experience with 300 BLK is Giving Back, but that may have been before the Rattler and the Hornady rounds got into their armory and, while he never went into much detail, he seemed to imply (if memory serves and I could be wrong) that it was an even more specific niche.

I imagine that Hornady's 190gr sub rounds do pretty well for their intended purpose; I've just never been really clear as to what that purpose was (excepting being really really quiet).

Give me a day or two to come back to this. I’m up to my ears in NPO stuff right now, and the mind is racing a bit much for a coherent answer this second. If I don’t post a lucid answer by end of the week, call me out by name to remind me that I said I’d address this.

Thanks for your patience.

[HCM]

We've talked before about how long, heavy, bullets at low velocity are more likely to yaw on impact. However, I've been led to believe and seen enough actual gel tests to conclude that yawing is not consistent unless high velocity bullets are specifically designed to do so.

I've read that the 220-grain Sierra Match King in .300BLK has been used 'operationally' (whatever that really means I do not know), but my understanding is, that it's use is primarily limited to things like sentry removal or other types of close-range covert work. Shot placement will emphasize immediate incapacitation (i.e., head shots). If you think about the roles that 147-grain subsonics from MP5-SDs were used for, that is now the realm of the .300BLK. I would figure the 220-grain SMK or the 190-grain Hornady Subsonic-X have superior terminal ballistics to a sub-sonic 9mm. However, for all intents and purposes sub-sonic .300BLK is just a big pistol round.

The advantage to a Rattler/other .300BO specific platform is the ease of suppression and the ability to swap to a far more effective loading when silence is no longer needed (i.e., the 110-grain Barnes loads) and gives you ~250-300y (maximum point blank) ability.

That Rattler is kind of a niche tool in many ways, but it is a much wider niche than pistols or SMGs. I'd rather carry a Rattler, MCX, adjustable gas-system equipped .300BO with a 10" barrel and a bunch of 110-grain bullets and a few mags of 190 or 220 subsonics than a rifle and SMG or rifle and suppressed pistol.

.300 black out was designed as a subsonic replacement for/ improvement on suppressing SMGs. It about doubles the effective range suppressed. The ability to switch ammo to supers is a plus but the role the rattler fills is closer to SMG than anything else.

[Wondering Beard]

Give me a day or two to come back to this. I’m up to my ears in NPO stuff right now, and the mind is racing a bit much for a coherent answer this second. If I don’t post a lucid answer by end of the week, call me out by name to remind me that I said I’d address this.

Thanks for your patience.

Take all the time you need.

[Tokarev]

Sorry, but watermelons?

Really?Don't knock watermelons.

Legend has it that General Curtis LeMay, after shooting watermelons at a picnic, was so impressed with the AR15 he approved it for the Air Force on the spot.



Sent from my SM-A505U using Tapatalk

[Norville]

I could give the watermelons a pass, but if he says “hydrostatic shock” one more time I’m out.

[paherne]

Have the NRA Attack Ninjas silenced MAC, yet? I watch his videos. I'm not sure whether I should be drunk or not when watching them, though.

[the Schwartz]

Don't knock watermelons.

Legend has it that General Curtis LeMay, after shooting watermelons at a picnic, was so impressed with the AR15 he approved it for the Air Force on the spot.



Sent from my SM-A505U using Tapatalk


Even if they aren't the best choice for a test analog, watermelons sure make for one helluva a visual display, don't they?

Given that not many folks pack 10% ordnance gelatin to picnics, I can see why the watermelons were chosen to 'stand in'. :)

[the Schwartz]

I don't know anything about ballistics so forgive me in advance. This just came out today. MAC suggests that subsonic will tumble out of the Rattler creating better terminal ballistics vs. zipping right through from the 9inch. No idea how watermelons stack up to ballistic gel or human tissue, but I was thinking about a Rattler or a 9inch AR pistol lately and I thought it might be interesting to discuss the ballistics of it all (subsonic and supersonic).

https://www.youtube.com/watch?v=rTxhMFqzqV0

Might be worth it...

The Hornady 'subbie' offering looks to offer some pretty decent performance:

59147

[Navin Johnson]

Might be worth it...

The Hornady 'subbie' offering looks to offer some pretty decent performance:

59147


What does this bring to the table ballistically compared to quality service caliber pistol rounds?

I can see better expansion relative to diameter and the high sectional density likely provides very consistent penetration.

Thanks for all your input.

[Sensei]

What does this bring to the table ballistically compared to quality service caliber pistol rounds?

I can see better expansion relative to diameter and the high sectional density likely provides very consistent penetration.

Thanks for all your input.

As others have said, itÂ’s the ability to insert a magazine loaded with these rounds once a supersonic crack is no longer an issue:

59242

The ability to shoot sentries in the head with a reasonably lethal subsonic round on infiltration, and then be able to immediately switch to a supersonic round with outstanding barrier penetration on exfiltration is very desirable to some parts of our military.

For civilians, even the best subsonic loads should only be used for things like nighttime hunting when you donÂ’t want to wake the neighbors. ItÂ’s fine for coyotes or boar. However, IÂ’d never take a subsonic load over the Barnes 110 grain black tip when my life is on the line.

[Odin Bravo One]

As some of you may know, I don’t give a fuck what gelatin test results look like. I care what meat and bone testing results look like. They are different often enough that the former holds very little sway over my ammunition selection decisions.

I’ve only used 110 TTSX and 220 OTM subs for social work, and if given the choice, I’ll take the subs all day.

The 110’s do a lot of damage to be sure. But they don’t suppress well, for what (I hope) are obvious reasons. The subs often don’t look terribly impressive on paper or in gel but the results they produce when popping skulls open is undeniable, and they are substantially quieter than their supersonic half-weight counterparts.

Since most infantry engagements are inside 200 yards, and most civilian engagements are substantially closer than that, the terminal differences between subs and supers are negligible. As for “outperforms” claims, according to who and in what capacity? When it comes to shooting assholes, If you can shoot, whatever you are shooting will outperform the ammunition being used by people who can’t shoot.

[the Schwartz]

Might be worth it...

The Hornady 'subbie' offering looks to offer some pretty decent performance:

59147



What does this bring to the table ballistically compared to quality service caliber pistol rounds?

I can see better expansion relative to diameter and the high sectional density likely provides very consistent penetration.

Thanks for all your input.


As a projectile expands in 10% ordnance gelatin or in human soft tissues, erosion kinematics briefly governs its behavior as a Bernoulli interface-stress balance expressed as ½ρ(V-U)² + YR = ½ρU² + RT within that regime. In the Bernoulli equation, V is the projectile's impact velocity and U is the nose-target interface velocity which is determined by the square root of the ratio of target to projectile densities. YR and RT are projectile and target yield strengths respectively. After the expansion/erosion regime ends, post-expansion projectile length dictates penetration depth in terms of a Poncelet flow regime expressed as X = LN(Vo/Vcritical)(SD/CD).

Since subsonic rounds are limited in terms of their maximum velocity (< 1,000 fps), the projectile's momentum must be increased to drive a fully expanded projectile deeper while retaining greater instantaneous velocities at depth. Increasing a projectile's momentum is most easily accomplished by increasing its mass. In both flow regimes, maximum terminal penetration depth is extremely sensitive to projectile length so a heavier—and commensurately longer—projectile afforded by larger (rifle) case length that allows for deeper seating of longer projectiles without impinging upon propellant volume makes sense. Even at subsonic velocities, greater post-expansion length (sectional density) equates to greater terminal penetration depth and higher velocities at depth.

Compared to service pistol-caliber rounds?

The larger case volume and length of rifle cases can launch significantly longer and heavier projectiles which means that post-expansion length (sectional density) surpasses that of the lighter, and much shorter, projectiles that are mandated by the limited case volumes available in service pistol-caliber cartridges. In addition to greater penetration depths, greater post-expansion sectional density (length) also means that the projectile retains higher velocity at those depths translating to greater strain energy storage within the tissues surrounding the bullet's path and increasing the likelihood of tissue damage needed to produce incapacitation.

[Wondering Beard]

As some of you may know, I don’t give a fuck what gelatin test results look like. I care what meat and bone testing results look like. They are different often enough that the former holds very little sway over my ammunition selection decisions.

I’ve only used 110 TTSX and 220 OTM subs for social work, and if given the choice, I’ll take the subs all day.

The 110’s do a lot of damage to be sure. But they don’t suppress well, for what (I hope) are obvious reasons. The subs often don’t look terribly impressive on paper or in gel but the results they produce when popping skulls open is undeniable, and they are substantially quieter than their supersonic half-weight counterparts.

Since most infantry engagements are inside 200 yards, and most civilian engagements are substantially closer than that, the terminal differences between subs and supers are negligible. As for “outperforms” claims, according to who and in what capacity? When it comes to shooting assholes, If you can shoot, whatever you are shooting will outperform the ammunition being used by people who can’t shoot.

Did you use barrels as short as the Rattler's 5.5" with subs?

It would seem that the velocity loss could really affect things, but I have no experience with either.

[Odin Bravo One]

Barrel length may make a difference on marginal hits (i.e., shitty shot placement). But I’ll lay dollars to pesos that if you drill them between the running lights, things like barrel length, subs versus supers arguments become irrelevant. But that’s my opinion, and worth what you paid for it.

[entropy]

Crap. I signed up to this thread as an elective. I didn’t know math was required.

I’m outta here!

[the Schwartz]

Crap. I signed up to this thread as an elective. I didn’t know math was required.

I’m outta here!

Basket-weaving and pottery class is down the hall, first classroom on the left past the custodian's closet. If you go past that, you'll end up in Poli-Sci class and you'll be on your own there. ;) /kidding

No real heavy math is needed. Don't let the equations bug you. Simply put, there are two regimes. Hydrodynamic regime is the first, where the projectile material flows/deforms under pressure like a liquid. After that is the Rigid/Static regime, where expansion stops, momentum decreases until the projectile comes to a stop. That's what the equations say, just in ''Nerd-ese''. :cool:

[SecondsCount]

Crap. I signed up to this thread as an elective. I didn’t know math was required.

I’m outta here!

Well, I think professor Giving Back just made it easier on you. It would seem that while the math and science are useful, what counts is time on the range so you can hit the target where it counts :cool:

[Odin Bravo One]

Now to be clear, (‘cause I don’t want people to misunderstand that what I’m saying is testing is junk science and should be ignored), I too once worshipped at the altar of ballistic gel. It has its uses. Mostly good for killing time when you cannot otherwise be shooting, or between wars, whatever. But an inordinate amount of time gets spent wrapped up in concerning oneself in minutiae that you do not need to concern yourself when it comes to shooting for all the marbles. A miss is a miss. Bad guys don’t care what ballistic gel studies showed. They often times don’t give a fuck about marginal hits either. One thing that cannot be argued, is that bad guys respect well placed shots, because they don’t have a choice in the matter.

Even then, there is nothing in the Bible of Ballistics that says an asshole will stop being an asshole with one well placed shot. Pick a round that works in your gun, is reasonably accurate (Sub-MOA/minute of asshole is sufficient), and you can shoot enough of to become proficient. Graveyards have been built for the people killed with supposedly shit ball military ammo. I’m confident that if you brain someone with any high powered rifle, your troubles with that person will be over rather quickly.

[the Schwartz]

Now to be clear, (‘cause I don’t want people to misunderstand that what I’m saying is testing is junk science and should be ignored), I too once worshipped at the altar of ballistic gel. It has its uses. Mostly good for killing time when you cannot otherwise be shooting, or between wars, whatever. But an inordinate amount of time gets spent wrapped up in concerning oneself in minutiae that you do not need to concern yourself when it comes to shooting for all the marbles. A miss is a miss. Bad guys don’t care what ballistic gel studies showed. They often times don’t give a fuck about marginal hits either. One thing that cannot be argued, is that bad guys respect well placed shots, because they don’t have a choice in the matter.

Even then, there is nothing in the Bible of Ballistics that says an asshole will stop being an asshole with one well placed shot. Pick a round that works in your gun, is reasonably accurate (Sub-MOA/minute of asshole is sufficient), and you can shoot enough of to become proficient. Graveyards have been built for the people killed with supposedly shit ball military ammo. I’m confident that if you brain someone with any high powered rifle, your troubles with that person will be over rather quickly.

I never took any of your commentary as suggesting that testing is junk science and should be ignored. Quite the contrary.

Good hits matter. More good hits matter more.


Even then, there is nothing in the Bible of Ballistics that says an asshole will stop being an asshole with one well placed shot.

Anyone who confuses ''terminal ballistic testing'' with ''tactics'' runs the risk of making the faulty assumption that terminal ballistic testing will predict the outcome of a gun fight. It won't.

In terminal ballistic testing we are concerned only with what the test medium does to the bullet (verifying that it'll expand correctly, especially after barriers), not with what the bullet does to the test medium.

Shoot—and hit—the threat until it is neutralized.

Of course, you already know that. :)

[Sensei]

As we approach the final moments of our society, anyone who shows up to the Great Battle of Our Lifetime with a PCC or a 300BO loaded with subs deserves to get punched in the nuts.

[Odin Bravo One]

Well there you have it.......

[Baldanders]

As we approach the final moments of our society, anyone who shows up to the Great Battle of Our Lifetime with a PCC or a 300BO loaded with subs deserves to get punched in the nuts.

I liked your post, but as someone who turned a sub2000 into a kick-ass Zombie Apocalypse gun, which I am proud to be handing back to my dad so he has a longarm for the these troubled times, I must also call you a fascist. 😉

One of my friends has it in his head that. .300BLK is optimal 200 yard hyper accuracy clambering for an AR build. Valid?

[HCM]

One of my friends has it in his head that. .300BLK is optimal 200 yard hyper accuracy clambering for an AR build. Valid?

If he is really your friend kick him in the nuts.

If not tell him him he is 100% correct.

[Sensei]

I liked your post, but as someone who turned a sub2000 into a kick-ass Zombie Apocalypse gun, which I am proud to be handing back to my dad so he has a longarm for the these troubled times, I must also call you a fascist. 😉

One of my friends has it in his head that. .300BLK is optimal 200 yard hyper accuracy clambering for an AR build. Valid?

I don’t know if I’d call it hyper-accurate. I’ve found the Barnes 110 grain black tip to be as accurate as any barrier blind factory 556 load out to 100 meters, and maybe a bit more up close (it creates a ragged hole under 1 inch when fired from the shoulder at 50 yards). Where the Barnes load shines is outstanding terminal performance (as judged by gel, boar, and deer) and reasonable external ballistics out to about 150 meter from a 9” barrel. You might be able to extend that out to 250ish meters with a 12” barrel but all of my 300blk rifles are 9” or less.

The problem with the 300blk is 1) legs beyond 300 meters or so in terms of external ballistics; choose 6.8SPC, 6.5CM, or even a heavy 556 for shots out to 300+ meters as the 300blk coming out the barrel at 2100 fps is dropping like a rock, 2) a bit of over penetration; expect about 20”.

[SecondsCount]

If he is really your friend kick him in the nuts.

If not tell him him he is 100% correct.

I laughed out loud.


I don’t know if I’d call it hyper-accurate. I’ve found the Barnes 110 grain black tip to be as accurate as any barrier blind factory 556 load out to 100 meters, and maybe a bit more up close (it creates a ragged hole under 1 inch when fired from the shoulder at 50 yards). Where the Barnes load shines is outstanding terminal performance (as judged by gel, boar, and deer) and reasonable external ballistics out to about 150 meter from a 9” barrel. You might be able to extend that out to 250ish meters with a 12” barrel but all of my 300blk rifles are 9” or less.

The problem with the 300blk is 1) legs beyond 300 meters or so in terms of external ballistics; choose 6.8SPC, 6.5CM, or even a heavy 556 for shots out to 300+ meters as the 300blk coming out the barrel at 2100 fps is dropping like a rock, 2) a bit of over penetration; expect about 20”.

I still see 300 BLK as a round that has a lot of energy out of a short barrel. 5.56 out of a 14.5 or 16" barrel has a flatter trajectory and half the wind drift, better accuracy in wind, higher velocity to insure fragmentation/expansion- not over penetration, costs less to manufacture/reload, and works awesome in the AR-15 that was designed for it.

In the middle we have 6.5G and 6ARC. While they may not have the energy of the BLK, they are more versatile for my type of uses.

[littlejerry]

I laughed out loud.



I still see 300 BLK as a round that has a lot of energy out of a short barrel. 5.56 out of a 14.5 or 16" barrel has a flatter trajectory and half the wind drift, better accuracy in wind, higher velocity to insure fragmentation/expansion- not over penetration, costs less to manufacture/reload, and works awesome in the AR-15 that was designed for it.

In the middle we have 6.5G and 6ARC. While they may not have the energy of the BLK, they are more versatile for my type of uses.

Technically the 6.8 SPC, 6.5G, and 6ARC all have more energy than 300 BLK at the muzzle, and they carry that advantage down range.

300 BLK is much closer to 5.56 when measuring ft-lbs of energy. Makes sense considering it uses the same case. The SPC, G, and ARC all use larger cases.

This is for a standard 16" barrel. Once you go short the larger diameter projectiles have an advantage in losing less velocity, but I'd still wager the 6.8 and 6.5 put down impressive numbers from SBRs

[Corse]

I don’t know if I’d call it hyper-accurate. I’ve found the Barnes 110 grain black tip to be as accurate as any barrier blind factory 556 load out to 100 meters, and maybe a bit more up close (it creates a ragged hole under 1 inch when fired from the shoulder at 50 yards). Where the Barnes load shines is outstanding terminal performance (as judged by gel, boar, and deer) and reasonable external ballistics out to about 150 meter from a 9” barrel. You might be able to extend that out to 250ish meters with a 12” barrel but all of my 300blk rifles are 9” or less.

The problem with the 300blk is 1) legs beyond 300 meters or so in terms of external ballistics; choose 6.8SPC, 6.5CM, or even a heavy 556 for shots out to 300+ meters as the 300blk coming out the barrel at 2100 fps is dropping like a rock, 2) a bit of over penetration; expect about 20”.

Even with the Sig rattler the Barnes 110 should expand out to 250 yrds.

[SecondsCount]

Technically the 6.8 SPC, 6.5G, and 6ARC all have more energy than 300 BLK at the muzzle, and they carry that advantage down range.

300 BLK is much closer to 5.56 when measuring ft-lbs of energy. Makes sense considering it uses the same case. The SPC, G, and ARC all use larger cases.

This is for a standard 16" barrel. Once you go short the larger diameter projectiles have an advantage in losing less velocity, but I'd still wager the 6.8 and 6.5 put down impressive numbers from SBRs

I think we are saying the same thing. The shorter the barrel, the better suited for 300 BLK but the other calibers, such as 6.5G, 6ARC, and 6.8 would work well and have better bullet offerings for extended distances.

[Sensei]

Even with the Sig rattler the Barnes 110 should expand out to 250 yrds.

I’ve published chrono results for the Sig Rattler with 110 Barnes at the bottom of the first page here:

https://pistol-forum.com/showthread.php?26978-Factory-Ammo-Chrono-Results-from-Various-Barrel-Lengths

You are getting roughly 1800 fps which is down to 1270 at 250 yards. You’ve also got a 2-foot holdover at that distance. My understanding of the Barnes load is that it expands down to 1400 fps which is going to be closer to 170 yards where the drop is a more manageable 7 inches.

[Baldanders]

If he is really your friend kick him in the nuts.

If not tell him him he is 100% correct.

Nah, he's a big dude like me and in better shape. He'd kick my ass.

[Baldanders]

I don’t know if I’d call it hyper-accurate. I’ve found the Barnes 110 grain black tip to be as accurate as any barrier blind factory 556 load out to 100 meters, and maybe a bit more up close (it creates a ragged hole under 1 inch when fired from the shoulder at 50 yards). Where the Barnes load shines is outstanding terminal performance (as judged by gel, boar, and deer) and reasonable external ballistics out to about 150 meter from a 9” barrel. You might be able to extend that out to 250ish meters with a 12” barrel but all of my 300blk rifles are 9” or less.

The problem with the 300blk is 1) legs beyond 300 meters or so in terms of external ballistics; choose 6.8SPC, 6.5CM, or even a heavy 556 for shots out to 300+ meters as the 300blk coming out the barrel at 2100 fps is dropping like a rock, 2) a bit of over penetration; expect about 20”.

I don't think my boy cares much about terminal ballistics, so .223 is probably better?

[RevolverRob]

I’ve published chrono results for the Sig Rattler with 110 Barnes at the bottom of the first page here:

https://pistol-forum.com/showthread.php?26978-Factory-Ammo-Chrono-Results-from-Various-Barrel-Lengths

You are getting roughly 1800 fps which is down to 1270 at 250 yards. You’ve also got a 2-foot holdover at that distance. My understanding of the Barnes load is that it expands down to 1400 fps which is going to be closer to 170 yards where the drop is a more manageable 7 inches.

1350, per Barnes Ammo Technician - https://pistol-forum.com/showthread.php?42065-300-AAC-Blackout-Enabling-Thread-(Mags-ammo-optics-barrels-etc-)&p=1075994&viewfull=1#post1075994

So, if you consider ~200y as the max engagement distance with a Rattler and 110 Barnes you should be good to go, might be right on the edge there. Basically, I think of a Rattler shooting supers as equivalent to a 16" .30-30. Yet, I can carry 60-rounds of Barnes and the gun in a backpack with some armor and med kit...It's f'ing ridiculous.

Still, none of it matters if you don't put the bullets on target. Which ultimately means practicing and training with the gun in question, whatever it is.

[RevolverRob]

I don't think my boy cares much about terminal ballistics, so .223 is probably better?

5.56 guns are a lot cheaper to shoot, period.

Even reloading 5.56 is cheaper. I'm cutting down and making .300BO brass and reloading my own. Still, my costs are roughly 0.23/round which is about 40% over what it cost to reload 5.56, and I'm using the cheapest .308" bullets I can (Speer TNT).

When it comes to cost .22LR, 9mm, 7.62x39, and 5.56 are the cheapest solutions out there.

[Corse]

I’ve published chrono results for the Sig Rattler with 110 Barnes at the bottom of the first page here:

https://pistol-forum.com/showthread.php?26978-Factory-Ammo-Chrono-Results-from-Various-Barrel-Lengths

You are getting roughly 1800 fps which is down to 1270 at 250 yards. You’ve also got a 2-foot holdover at that distance. My understanding of the Barnes load is that it expands down to 1400 fps which is going to be closer to 170 yards where the drop is a more manageable 7 inches.

Revolver Rob already passed the info, but this is from another thread:


The minimum IMPACT velocity required for reliable expansion and penetration on these 30 caliber bullets is as follows-
For the-

#30321 110 gr TAC-TX (with the large black colored tip designed for the 300 Blackout) needs 1350 fps.
#30320 120 gr TAC-TX (with the large black colored tip designed for the 300 Blackout) needs 1350 fps.

#30358 110 gr TAC-TX (with blue tip designed for 308 Win velocities and higher) needs 2000 fps.
#30362 110 gr TTSX (with blue tip designed for 308 Win velocities and higher) needs 2000 fps.
FYI- #30358 and #30362 are the same bullet just put into a different box.

#30336 110 gr TAC-X need a minimum of 1900 fps.
#30341 110 gr TSX need a minimum of 1900 fps.
FYI #30336 and #30341 are the bullet just put into a different box.

#30364 130 gr TTSX needs a minimum of 1800 fps.

I've seen some chrono'd speed from a rattler at ~1900 FPS. I'll look later to see what I was getting from my SR30 with factory ammo, with reloads I hit 2300 FPS using barnes data.

[El Cid]

Now to be clear, (‘cause I don’t want people to misunderstand that what I’m saying is testing is junk science and should be ignored), I too once worshipped at the altar of ballistic gel. It has its uses. Mostly good for killing time when you cannot otherwise be shooting, or between wars, whatever. But an inordinate amount of time gets spent wrapped up in concerning oneself in minutiae that you do not need to concern yourself when it comes to shooting for all the marbles. A miss is a miss. Bad guys don’t care what ballistic gel studies showed. They often times don’t give a fuck about marginal hits either. One thing that cannot be argued, is that bad guys respect well placed shots, because they don’t have a choice in the matter.

Even then, there is nothing in the Bible of Ballistics that says an asshole will stop being an asshole with one well placed shot. Pick a round that works in your gun, is reasonably accurate (Sub-MOA/minute of asshole is sufficient), and you can shoot enough of to become proficient. Graveyards have been built for the people killed with supposedly shit ball military ammo. I’m confident that if you brain someone with any high powered rifle, your troubles with that person will be over rather quickly.

Thank you! Always appreciate when a legit end user contributes to technical discussions. Did y’all have a preferred bbl length?

[HCM]

I don't think my boy cares much about terminal ballistics, so .223 is probably better?

Going back to your original question 300 black has done niche uses:

Suppressed .300 BO SBR > suppressed 9mm SMG

Can put Supers in it and get 39-30/7.62x39 rifle like performance out to 200 yards.

Can put it in a 16” AR /AR upper for places you can’t hunt with 5.56 etc but you get the sane effective range as a 30-30 lever gun.

No matter how well it might group at 200 (ok but nothing special) the excessive hold over at distance is a deal breaker.

[Sensei]

Going back to your original question 300 black has done niche uses:

Suppressed .300 BO SBR > suppressed 9mm SMG

Can put Supers in it and get 39-30/7.62x39 rifle like performance out to 200 yards.

Can put it in a 16” AR /AR upper for places you can’t hunt with 5.56 etc but you get the sane effective range as a 30-30 lever gun.

No matter how well it might group at 200 (ok but nothing special) the excessive hold over at distance is a deal breaker.

I think this is pretty much spot on.


What follows is not directed at HCM. Honestly, I get confused by these threads. Perhaps the 110 Barnes will expand out to roughly 175-225 yards. But to what ends? To those encouraged that it expands beyond 175 yards, keep in mind you will have a 110 grain, .30 caliber bullet traveling at 1350-1450 fps. So, what do you expect it to expand to, exactly? Penetrating to what depth? Also, has anyone independently verified these expansion thresholds at sub-rifle velocities?

My suspicion is that it will produce a wound profile that looks something less than what a 115 grain +P 9mm JHP produces - shallow and no temporary cavity to write home about. Most consider that to be less than ideal. So, I stopped trying to make my Rattler be all things. That means I don’t have a LPVO on my 5” rifle to account for the 2 foot drop at 250 yards. Mine is set up to engage 2 legged critters out to about 50 yards max. At that distance, I have no holdovers and still get some temporary cavitation. If I need to engage targets beyond 50 yards, I’m using something that still behaves like a rifle at that distance (9” 300blk, 11.5-14.5” 556, 762x39, 338LM, 50BMG, etc.

59562

Finally, subs in the 300blk. Is there any doubt that loading the Rattler with subs is going to give it something less than 9mm PCC performance? If people accept that premise, is the answer to always make head shots? I ask because that is what I seem to be reading.

[Odin Bravo One]

Thanks for the reminders.

[Caballoflaco]

Finally, subs in the 300blk. Is there any doubt that loading the Rattler with subs is going to give it something less than 9mm PCC performance? If people accept that premise, is the answer to always make head shots? I ask because that is what I seem to be reading.

I’m not saying this should or should not be a driving factor on ammo selection, but an interesting effect of a long pointy bullet with good sectional density is that they’re capable of penetrating soft armor that will stop handgun rounds, even at subsonic velocities.

[the Schwartz]

I’m not saying this should or should not be a driving factor on ammo selection, but an interesting effect of a long pointy bullet with good sectional density is that they’re capable of penetrating soft armor that will stop handgun rounds, even at subsonic velocities.

Do you have evidence of this for the ammunition (subsonics) presently being discussed?

The reason I ask is that with lead core projectiles, defeating soft armor is a function of pressure dissipation rate (integrated with respect to time) that exceeds the longitudinal shock hugoniot of the aramid strand.

With slower projectiles that more readily deform against such resistance (RT in my prior post), impact force spread across a larger area due to projectile expansion reduces the magnitude of the pressure while concurrently lengthening the time frame of the pressure impulse reducing the strain rate and the likelihood that the aramid strand will fail under load.

[Caballoflaco]

Do you have evidence of this for the ammunition (subsonics) presently being discussed?

The reason I ask is that with lead core projectiles, defeating soft armor is a function of pressure dissipation rate (integrated with respect to time) that exceeds the longitudinal shock hugoniot of the aramid strand.

With slower projectiles that more readily deform against such resistance (RT in my prior post), impact force spread across a larger area due to projectile expansion reduces the magnitude of the pressure while concurrently lengthening the time frame of the pressure impulse reducing the strain rate and the likelihood that the aramid strand will fail under load.

There’s a few videos out there showing penetration of lvl II vests. I also remember reading similar reports of heavy subsonic 762x39 being capable of the same back before .300BLK was a thing. Lvl III seems to stop it from the little research I’ve done.


https://youtu.be/bk0kBMYNHnE


Not a huge fan of MAC, testing starts around 7:00, also note the expanding leheigh(so) doesn’t penetrate.

https://youtu.be/euucD2YJq4w

[the Schwartz]

There’s a few videos out there showing penetration of lvl II vests. I also remember reading similar reports of heavy subsonic 762x39 being capable of the same back before .300BLK was a thing. Lvl III seems to stop it from the little research I’ve done.


https://youtu.be/bk0kBMYNHnE


Not a huge fan of MAC, testing starts around 7:00, also note the expanding leheigh(so) doesn’t penetrate.

https://youtu.be/euucD2YJq4w

Thanks for the links. Pretty much confirms my suspicions that anything greater that Level IIIa and higher will stop subsonic projectiles unless there's a hardened penetrator present in the projectile's construction. Not seeing Levels IIa and II as acceptable armor options (my preference personally is no less than IIIa) due to their lower resistance to higher energy (aka, velocity) threats, I tend to discount anything less than IIIa as an option. As alluded to a sentence or two ago, the presence of a hardened penetrator increases the likelihood that subsonic munitions might defeat heavier laminates by eliminating the reduction in the pressure interface balance brought about by deformation.

The "gold standard" in defeating thin targets composed of materials with high strain rate failure criteria is energy (velocity). This means that a greater return for investment from increasing velocity will be realized over that of increasing mass. It is possible to cause projectiles composed of softer materials to defeat targets made of harder materials than the projectile. This requires the use of extremely high speeds (called "critical velocity" by Alexseevskii & Tate, 1967) to drive the projectile fast enough to exceed the resistant pressure of the harder target material even in cases where the projectile might be treated as a 'zero-strength' jet.

I agree with your assessment about the capabilities of Level III armor in defeating subsonic projectiles.

[Caballoflaco]

One of the things the Rooskies do with their 9x39 subsonic loads is use large and heavy steel penetrators in them.

59611

While it’s hard to find confirmable open source info on effectiveness it’s interesting to note that they’ve been using these for going on 30 years now and they continue to issue the rifles and subsonic ammunition to folks going into harms way.

[the Schwartz]

One of the things the Rooskies do with their 9x39 subsonic loads is use large and heavy steel penetrators in them.

59611

While it’s hard to find confirmable open source info on effectiveness it’s interesting to note that they’ve been using these for going on 30 years now and they continue to issue the rifles and subsonic ammunition to folks going into harms way.

Like you're reading my mind, Senor Caballo.

The Soviets clearly paid attention to Alekseevskii's LRKEP research on both eroding and non-eroding penetrator performance when they designed their penetrators. Especially in the non-eroding/rigid penetration regime larger L/D ratios, < 3, translate to higher control volumes in the elastic/plastic field that forms ahead of the penetrator nose. These lengthier projectiles demand a large case volume behind them for obvious spatial issues (projectile impingement on propellant capacity, adequate gas volume to maintain pressure against expansion volume, etc.) , pistol caliber cases need not apply.

[HCM]

I think this is pretty much spot on.


What follows is not directed at HCM. Honestly, I get confused by these threads. Perhaps the 110 Barnes will expand out to roughly 175-225 yards. But to what ends? To those encouraged that it expands beyond 175 yards, keep in mind you will have a 110 grain, .30 caliber bullet traveling at 1350-1450 fps. So, what do you expect it to expand to, exactly? Penetrating to what depth? Also, has anyone independently verified these expansion thresholds at sub-rifle velocities?

My suspicion is that it will produce a wound profile that looks something less than what a 115 grain +P 9mm JHP produces - shallow and no temporary cavity to write home about. Most consider that to be less than ideal. So, I stopped trying to make my Rattler be all things. That means I don’t have a LPVO on my 5” rifle to account for the 2 foot drop at 250 yards. Mine is set up to engage 2 legged critters out to about 50 yards max. At that distance, I have no holdovers and still get some temporary cavitation. If I need to engage targets beyond 50 yards, I’m using something that still behaves like a rifle at that distance (9” 300blk, 11.5-14.5” 556, 762x39, 338LM, 50BMG, etc.

59562

Finally, subs in the 300blk. Is there any doubt that loading the Rattler with subs is going to give it something less than 9mm PCC performance? If people accept that premise, is the answer to always make head shots? I ask because that is what I seem to be reading.

I think you are spot in. Like the 300 BO round, the Rattler is a niche item. It’s good at what it does but if it was the do all wonderkind some make it out to be full size guns would not exist.