A thread last year ( Home defense thread) sent me down a rabbit hole looking for interior wall testing of 300blk ammunition. I couldn't find much, so I decided to do a bit of "Box of Truth" style testing myself.
Disclaimers, caveats and thank yous to start with:
This is a drywall penetration test of a few supersonic and subsonic 300blk commercial loadings from several different barrel lengths of 300blk chambered firearms. We also shot a 77gr OTM 5.56 from a 10.3 AR and 124gr Federal HST from a Glock 47 as comparison points.
The four walls used for testing are made of 2x4s on 16" centers with sheetrock on the front and back, typical of American home construction interior walls. The walls were spaced 10 feet apart, and the first wall was shot from 10 feet away with a 5.5" 1:5 Twist 300blk MCX Rattler and a 9" 1:5 twist 300blk MCX Virtus. When we got interesting results or discrepancies between the 5.5 and 9 data, we also conducted a third test using Jim's 7" AR-15 in 300blk. The goal was to determine if any 300blk loading tested, supersonic or subsonic, could perform similarly to 77gr OTM 5.56.
Why compare to 5.56? I'll leave a quote from Dr. Gary Roberts here to explain:
That being said, this is not a "which round is best", "why x is great and y is trash", "this is the only ammo you should use for home defense", or anything else. It's just data on how some 300blk behaved in the worst possible barrier to rely on, an empty interior wall of a standard American home. I'm not telling you what to use or not use. You're an adult. Use your brain and make your own decisions.
If you take nothing else from this test, trust that everything that can stop a threat can penetrate multiple interior walls. Train hard and don't miss, whatever you're using. But since you are legally and morally responsible for that bullet, wherever it ends up, I think more information and testing is better to rely on than anecdotes and gunshop counter mythos.
As a final disclaimer, I'm not a ballistics professional, been there done that operator, or any other credential to use as an appeal to authority, just a Texan with a gun, questions, and time to ask them on the range. Comments or opinions on round performance are possibly dumb and certainly my own, and no ammo company provided anything to me, much less know or care that I exist.
Most importantly, a huge thank you to jrb2019/Sheepdog. Without him, this would not have happened, period. He built the walls, volunteered his personal range, used his chronograph and spent several hours with me poking holes in sheetrock and recording the results. Can't thank him enough.
I have broken the testing footage into individual videos for each cartridge, so you're not stuck scrolling through 20 minutes of video if theres a specific load that you're interested in seeing. That also lets me add a few thoughts in between videos on the results we saw.
I hope this is informational or if nothing else, mildly entertaining viewing. Thanks for checking it out.
The test set up:
The guns:
A few of the test rounds: 110gr Barnes Tac-Tx, 85gr Spicy Boi, 188gr Selous, 200gr Slow Papi
First, the 77gr OTM 5.56 that I wanted to compare to:
77gr imi razorcore open tip match bullet from 10.3" AR: 2383 fps.
Already yawing exiting first wall, tumbling in 2 and 3, horizontal in 4 and in target beyond. This kind of yaw/tumbling and the resulting velocity loss is exactly what I was hoping to find in a 300blk loading as well, and the reason the AR in 5.56 is the CQB/SWAT/Home Defense standard it is today…good terminal effects with reduced (not zero) risk to bystanders after passing through an intermediate barrier.
We actually shot the 9mm test last, but I wanted to put it up top here to give the other end of the performance spectrum before we get into the 300blk tests.
9mm HST penetrated cleanly through all four walls, no yaw, tumble, deflection, expansion...just penetration. Spoiler alert: some of the 300blk tests are going to look real similar to this one.
Both our 5.56 and 9mm results were similar to tests done by others, with no real surprises.
Moving on to the meat and potatoes of the testing with supersonic 300blk loads, starting with one of my favorite loads, 110gr Barnes Tac-Tx.
Tac-Tx penetrated well with minimal yaw or deflection. Bullet started to open a little but that had very little impact on velocity or direction. This tracks with other testing I've seen of other 30cal projectiles like 7.62x39, which tend to move through drywall with minimal deflection and therefore likely retain most of their velocity, and is how I was afraid all of the 300blk loads were going to perform.
Next up, 110gr Hornady Vmax.
The vmax did fragment into 3 pieces in the 9" gun, but continued to penetrate well after fragmenting. In the 5.5" gun we saw no opening of bullet, tumbling or deflection, just straight through the walls.
The next load was one I was super interested to see, Phantom Defense 85gr Spicy Boi.
The 85gr velocities were very impressive, as was expanding some in just dry wall. Zero yaw or deflection though. Probably a great round on target, but does not limit overpenetration risk. Would love to see how it does as a hunting round though.
Moving onto the subsonic ammo, starting with 220gr Sig OTM.
Punched right through with the 9" gun, very similar to 9mm performance. Lowered velocity out of the 5.5" seemed to induce some yaw/tumble. This was the first test other than 110gr Vmax where we had different performance from 9" and 5.5" barrels, and made me feel slightly less crazy for wanting to test both.
Next up, 188gr Selous Expander from Discrete Ballistics.
Like the 85gr spicy boi, positive to see expansion even in just drywall, but little yaw or deviation other than after the 4th wall for the 9". 9" also opened noticeably more than 5.5". Neat that 70 fps can make that big a difference in how much the round expands.
On to 205gr Sig Varmint Tip
Wild deflection first test. Bullets do weird things when they hit stuff, even easy to go through stuff like drywall.. The projectile hit the berm backwards and was embedded inch or so in the railroad tie so velocity was significantly slowed. Sideways impacts show good velocity shedding, but I have some questions about terminal effect on intended target. Slowest moving projectile all day, one anomalous chrono reading as well. Bad data, huge SD of round? Not sure. Would really like to see how good this round is for hunters, wall performance was promising.
Red circle where we found the round stuck in the berm:
Recovered bullet:
124gr 9mm and 205gr 300blk impacts next to each other:
200gr Phantom Defense Slow Papi
Velocity was great. Keeping it barely subsonic. It was running hotter from the Rattler than some rounds from the 9" gun. Would love to see performance on hogs. Walls did exactly nothing to slow it down though.
Last round we tested was 190gr Hornady Sub-X
Really promising that it tumbles quickly. Similar to the sig 205 grain, would love input from people who have used it on hogs/etc regarding terminal performance, because it did very well tumbling and slowing down after hitting drywall.
Here's the round that hit the stud in wall three and we found on the ground behind wall four.
Ending thoughts:
There were absolutely a couple interesting things we learned in testing. The Phantom Defense loads are absolutely smoking velocity wise. Their loads in the 5.5" Rattler were moving faster than most other loads out of the 9" MCX in both supersonic and subsonic loadings. Thats wild. The 85gr load also expanded some in just drywall. It may have not outperformed 77gr OTM on this test but I'd love to try it on hogs.
Speaking of expansion it was neat to see Discrete Ballistics 188gr Selous open up with both barrel lengths in just drywall, and the difference in expansion based on barrel length/velocity.
The 205gr Sig and the 190gr Sub X were both the slowest subs we tried and the best at tumbling/velocity shedding. If anyone has lots of experience with either of these rounds on hogs/deer/wendigos let me know because if they have good terminal performance they did well in this testing and look like interesting options.
And I'm glad we tested 77gr OTM 5.56 and 124gr 9mm HST, which both performed as expected based on lots of testing other people have done. They gave us really good benchmarks to judge from on opposite ends of the spectrum.
We had a few promising results from 190gr Sub-X and 205gr Sig Varmint loads. Just as one more point of comparison (and I know KE is not the end all be all to measure ballistic effectiveness).
77gr 5.56 @ 2383 fps: 971 ft.lbf
205gr 300blk @ 978 fps: 435 ft.lbf
190gr 300blk @ 1005 fps: 426 ft.lbf
124gr 9mm @ 1130 fps: 352 ft.lbf
For me, given the proven track record of 77gr OTM 5.56, I'm going to be sticking with it in my personal home defense AR. But it was a lot of fun testing out some of the 300blk options, and its nice to know what loads I should use in my MCX if overpenetration is a concern.
Hope this was educational/entertaining for yall. Thanks again to jrb2019, and if he has any thoughts I missed I hope he chimes in.
Disclaimers, caveats and thank yous to start with:
This is a drywall penetration test of a few supersonic and subsonic 300blk commercial loadings from several different barrel lengths of 300blk chambered firearms. We also shot a 77gr OTM 5.56 from a 10.3 AR and 124gr Federal HST from a Glock 47 as comparison points.
The four walls used for testing are made of 2x4s on 16" centers with sheetrock on the front and back, typical of American home construction interior walls. The walls were spaced 10 feet apart, and the first wall was shot from 10 feet away with a 5.5" 1:5 Twist 300blk MCX Rattler and a 9" 1:5 twist 300blk MCX Virtus. When we got interesting results or discrepancies between the 5.5 and 9 data, we also conducted a third test using Jim's 7" AR-15 in 300blk. The goal was to determine if any 300blk loading tested, supersonic or subsonic, could perform similarly to 77gr OTM 5.56.
Why compare to 5.56? I'll leave a quote from Dr. Gary Roberts here to explain:
Quote:
Given the widespread availability of this information for over a decade, I am shockingly surprised to read about the "overpenetration" with "high powered assault rifles". In this day and age anyone who is spouting this BS needs to be horsewhipped… Several respected organizations have done structural wall testing, including the FBI, CHP, and IWBA. In our IWBA and CHP testing, replicas of standard construction interior walls were fabricated using two pieces of 1/2 thick dry wall cut in 12 x 24 segments and mounted four inches apart using 2 x 4 fir studs and 1.5 dry wall screws. Five rounds of each load were first fired into bare gelatin to serve as controls. Then 5 shots of each load were shot through interior wall segments into gelatin blocks placed a set distance behind the intermediate barriers various distances have been tested, typically ranging from 1 to 10 feet.
Generally, common service caliber JHP bullets failed to expand and had very deep, excessive penetration after passing through the interior wall, due to plugging of the hollow point. With the hollow point plugged, the bullets performed nearly identically to FMJ pistol bullets. The terminal performance of the 12 ga. 00 buckshot and slugs was not altered by passing through interior wall replicas, with penetration and deformation nearly identical with their performance in bare gelatin. Likewise, .308 rounds were not usually effected by the presence of an interior wall intermediate barrier.
With one exception, the majority of the 5.56 mm/.223 loads, including M855 62 gr "green-tip" FMJ, which were fired through interior walls demonstrated either minimal changes in terminal performance compared with bare gelatin or reduced penetration. The major exception were 55 gr M193 style FMJ projectiles which exhibited minimal fragmentation and deformation after first passing through interior wall replicas and hence penetrated deeper than in bare gel.
Since all of the 5.56 mm/.223 bullets fired through the interior wall had significantly less penetration than 9 mm, .40 S&W, .45 ACP, and 12 ga. shotgun projectiles which were fired through an interior wall, stray 5.56 mm/.223 bullets seem to offer a reduced risk of injuring innocent bystanders and an inherent reduced risk of civil litigation in situations where bullets miss their intended target and enter or exit structures. As such, 5.56mm/.223 caliber weapons may be safer to use in CQB situations and crowded urban environments than service caliber handguns or 12 ga. weapons.
Obviously, it is important to keep in mind that purpose built barrier blind 5.56 mm/.223 projectiles, such as the 55 & 62 gr Federal Tactical JSP's and the Nosler 60 gr Partition, will offer deeper penetration than fragmenting designs and may exit.
That being said, this is not a "which round is best", "why x is great and y is trash", "this is the only ammo you should use for home defense", or anything else. It's just data on how some 300blk behaved in the worst possible barrier to rely on, an empty interior wall of a standard American home. I'm not telling you what to use or not use. You're an adult. Use your brain and make your own decisions.
If you take nothing else from this test, trust that everything that can stop a threat can penetrate multiple interior walls. Train hard and don't miss, whatever you're using. But since you are legally and morally responsible for that bullet, wherever it ends up, I think more information and testing is better to rely on than anecdotes and gunshop counter mythos.
As a final disclaimer, I'm not a ballistics professional, been there done that operator, or any other credential to use as an appeal to authority, just a Texan with a gun, questions, and time to ask them on the range. Comments or opinions on round performance are possibly dumb and certainly my own, and no ammo company provided anything to me, much less know or care that I exist.
Most importantly, a huge thank you to jrb2019/Sheepdog. Without him, this would not have happened, period. He built the walls, volunteered his personal range, used his chronograph and spent several hours with me poking holes in sheetrock and recording the results. Can't thank him enough.
I have broken the testing footage into individual videos for each cartridge, so you're not stuck scrolling through 20 minutes of video if theres a specific load that you're interested in seeing. That also lets me add a few thoughts in between videos on the results we saw.
I hope this is informational or if nothing else, mildly entertaining viewing. Thanks for checking it out.
The test set up:
The guns:
A few of the test rounds: 110gr Barnes Tac-Tx, 85gr Spicy Boi, 188gr Selous, 200gr Slow Papi
First, the 77gr OTM 5.56 that I wanted to compare to:
77gr imi razorcore open tip match bullet from 10.3" AR: 2383 fps.
Already yawing exiting first wall, tumbling in 2 and 3, horizontal in 4 and in target beyond. This kind of yaw/tumbling and the resulting velocity loss is exactly what I was hoping to find in a 300blk loading as well, and the reason the AR in 5.56 is the CQB/SWAT/Home Defense standard it is today…good terminal effects with reduced (not zero) risk to bystanders after passing through an intermediate barrier.
We actually shot the 9mm test last, but I wanted to put it up top here to give the other end of the performance spectrum before we get into the 300blk tests.
9mm HST penetrated cleanly through all four walls, no yaw, tumble, deflection, expansion...just penetration. Spoiler alert: some of the 300blk tests are going to look real similar to this one.
Both our 5.56 and 9mm results were similar to tests done by others, with no real surprises.
Moving on to the meat and potatoes of the testing with supersonic 300blk loads, starting with one of my favorite loads, 110gr Barnes Tac-Tx.
Tac-Tx penetrated well with minimal yaw or deflection. Bullet started to open a little but that had very little impact on velocity or direction. This tracks with other testing I've seen of other 30cal projectiles like 7.62x39, which tend to move through drywall with minimal deflection and therefore likely retain most of their velocity, and is how I was afraid all of the 300blk loads were going to perform.
Next up, 110gr Hornady Vmax.
The vmax did fragment into 3 pieces in the 9" gun, but continued to penetrate well after fragmenting. In the 5.5" gun we saw no opening of bullet, tumbling or deflection, just straight through the walls.
The next load was one I was super interested to see, Phantom Defense 85gr Spicy Boi.
The 85gr velocities were very impressive, as was expanding some in just dry wall. Zero yaw or deflection though. Probably a great round on target, but does not limit overpenetration risk. Would love to see how it does as a hunting round though.
Moving onto the subsonic ammo, starting with 220gr Sig OTM.
Punched right through with the 9" gun, very similar to 9mm performance. Lowered velocity out of the 5.5" seemed to induce some yaw/tumble. This was the first test other than 110gr Vmax where we had different performance from 9" and 5.5" barrels, and made me feel slightly less crazy for wanting to test both.
Next up, 188gr Selous Expander from Discrete Ballistics.
Like the 85gr spicy boi, positive to see expansion even in just drywall, but little yaw or deviation other than after the 4th wall for the 9". 9" also opened noticeably more than 5.5". Neat that 70 fps can make that big a difference in how much the round expands.
On to 205gr Sig Varmint Tip
Wild deflection first test. Bullets do weird things when they hit stuff, even easy to go through stuff like drywall.. The projectile hit the berm backwards and was embedded inch or so in the railroad tie so velocity was significantly slowed. Sideways impacts show good velocity shedding, but I have some questions about terminal effect on intended target. Slowest moving projectile all day, one anomalous chrono reading as well. Bad data, huge SD of round? Not sure. Would really like to see how good this round is for hunters, wall performance was promising.
Red circle where we found the round stuck in the berm:
Recovered bullet:
124gr 9mm and 205gr 300blk impacts next to each other:
200gr Phantom Defense Slow Papi
Velocity was great. Keeping it barely subsonic. It was running hotter from the Rattler than some rounds from the 9" gun. Would love to see performance on hogs. Walls did exactly nothing to slow it down though.
Last round we tested was 190gr Hornady Sub-X
Really promising that it tumbles quickly. Similar to the sig 205 grain, would love input from people who have used it on hogs/etc regarding terminal performance, because it did very well tumbling and slowing down after hitting drywall.
Here's the round that hit the stud in wall three and we found on the ground behind wall four.
Ending thoughts:
There were absolutely a couple interesting things we learned in testing. The Phantom Defense loads are absolutely smoking velocity wise. Their loads in the 5.5" Rattler were moving faster than most other loads out of the 9" MCX in both supersonic and subsonic loadings. Thats wild. The 85gr load also expanded some in just drywall. It may have not outperformed 77gr OTM on this test but I'd love to try it on hogs.
Speaking of expansion it was neat to see Discrete Ballistics 188gr Selous open up with both barrel lengths in just drywall, and the difference in expansion based on barrel length/velocity.
The 205gr Sig and the 190gr Sub X were both the slowest subs we tried and the best at tumbling/velocity shedding. If anyone has lots of experience with either of these rounds on hogs/deer/wendigos let me know because if they have good terminal performance they did well in this testing and look like interesting options.
And I'm glad we tested 77gr OTM 5.56 and 124gr 9mm HST, which both performed as expected based on lots of testing other people have done. They gave us really good benchmarks to judge from on opposite ends of the spectrum.
We had a few promising results from 190gr Sub-X and 205gr Sig Varmint loads. Just as one more point of comparison (and I know KE is not the end all be all to measure ballistic effectiveness).
77gr 5.56 @ 2383 fps: 971 ft.lbf
205gr 300blk @ 978 fps: 435 ft.lbf
190gr 300blk @ 1005 fps: 426 ft.lbf
124gr 9mm @ 1130 fps: 352 ft.lbf
For me, given the proven track record of 77gr OTM 5.56, I'm going to be sticking with it in my personal home defense AR. But it was a lot of fun testing out some of the 300blk options, and its nice to know what loads I should use in my MCX if overpenetration is a concern.
Hope this was educational/entertaining for yall. Thanks again to jrb2019, and if he has any thoughts I missed I hope he chimes in.
