Going back to my previous post on 300 Blackout, Terminal Effect has been keeping a close eye on Lehigh Defense and their ever-changing product line. Their new 78 grain “Close Quarters” bullet boasts impressive performance that would appeal to anyone operating in a constrained indoor environment. We decided to put their claims to the test.
A New Approach to an Old Problem
Normally, 300 Blackout bullet weights bottom out at 110 grains. Lehigh Defense’s new 78 grain offering not only bucks tradition with its light-for-caliber weight, but also in its construction. It’s not often that you see aluminum representing almost a third of a bullet’s mass and dominating its exterior construction.
To better understand this unique factory loading, we pulled a round apart to study its components using an inertia hammer. This actually took considerable effort since the 78 grain bullet is so light and is seated with a formidable crimp.
NOTE: Do not attempt to pull live rounds in this manner at home.
The powder charge came in at 19.1 grains, and actually uses the same powder as Lehigh Defense’s 170 grain subsonic controlled fracturing load. Since they do not publish reloading data for their bullets and only suggest using starting loads for other bullets of similar weight, this satisfied some of my curiosity in this area. It goes without saying that potential reloaders should use extreme caution and start with a low charge when attempting to load for a new bullet.
When spread out, the round’s powder charge exhibits multiple grain types, unlike other common types of 300 Blackout powder such as ‘Lil Gun and H110.
Bullet Weight: 78.0 grains
Powder Charge: 19.1 grains
Primer: Small rifle
Since this round is advertised as a “Close Quarters” solution, we decided to take a more comprehensive approach in reviewing it compared to standalone gel tests. Lehigh Defense makes the following relevant claims on their product page:
Penetration Min (in) Base/Nose: 9
Penetration Min (in) Petals: 12
Expansion Min (in) Petals Radial / Dia.: 4 / 8
Based on these figures, the bullet should enter the gel block, expand or fracture, and then deliver solid penetration with the five base fragments in an 8 inch diameter wound pattern. In a real world target, this would equate to vitals penetration with the base fragments with none of the bullets exiting the target, and the nose causing a significant flesh wound at a minimum.
Our first test was simply shooting a 5 gallon bucket of water in an attempt to recover the resulting bullet fragments.
I’ve seen plenty of water jugs shot before, but what I didn’t expect was the entire bucket to crack open. The hydraulic pressure created by the round dumping its energy was significantly more than I was anticipating.
Only two fragments were recovered after a thorough search of the surrounding area.
The aluminum nose portion of the bullet was recovered a few feet directly behind the bucket. Other than the black marks on one side, it held up remarkably well, with only a slight warping along its length which was only apparent upon spinning it. Based on the channels machined into the stem, it appears that the nose may be screwed into the base during manufacturing.
The only other fragment was recovered several feet to the right of the bucket. It appears to have fractured and broken off from the base as designed. The edges are jagged and quite sharp.
The nose piece weighed in at 22.3 grains, which accounts for nearly a third (~28.5%) of the bullet’s overall weight.
The recovered fragment weighed 11.1 grains. Assuming this is a representative weight for the other three petals, that would bring the total accounted-for weight up to 44.4 grains. Adding the aluminum nose brings the total to 66.7, indicating that the penetrating base of the bullet’s brass portion might weigh about 11.3 grains.
Before shooting the gel block, we fired five rounds through a chronograph at 10′ to measure the velocity variation between different cartridges from the same lot.
The results are charted on the table below:
|Shot #||Measured Velocity|
This gives us an average of 2807.2 fps with a standard deviation of only 3.11, which is very good. While this is a small sample size and does not speak conclusively for this ammunition, it is a good initial result. It was also impressive that this ammunition achieved such a high velocity from a 10.5″ barrel, since Lehigh Defense only quotes 2800 fps from a 16″ barrel. This is good news for SBR owners, since many shooters choose 300 Blackout due to its high efficiency in barrels 10″ and shorter.
10% Ballistics Gel
Rather than simply shoot a block of gel, we decided to enclose it in simulated interior walls. Made from 5/8″ drywall and standard 2x4s, these represent what exiting bullets or fragments would encounter in a typical American home. Each wall segment is 12×16″. Due to significant wind on the testing day, the segments were held together by small 2×4 segments and screws on the top corners.
The gel block is a Clear Ballistics 6x6x16″ FBI block made of synthetic 10% ballistics gelatin. The block was shot as received in the packaging at an outside temperature of 65°F. The bullet clocked in at 2808 FPS from a 10.5″ barrel and was fired from a distance of 10′.
With the interior wall surfaces being 12″ apart, taking the video frame by frame shows the block almost touching them on the first frame of expansion, indicating about 10″ of temporary cavity at its peak. A higher framerate camera would be required for more precise analysis.
The bullet struck the block low center, but no portion of the bullet exited. The temporary cavity expansion was so forceful that it punched a 4″ diameter hole through the face of the sturdy resin table it was sitting on.
A thorough inspection of the drywall yielded satisfactory results – none of the bullet fragments had exited the block, let alone made their way into the wall segments. This is good news for a round advertised under the “Close Quarters” moniker, since overpenetration can be a disaster in these types of environments.
Once we were satisfied that the interior walls were intact, they were removed for a thorough inspection of the gel block.
Despite striking the block about 1.5″ from the table, the round manage to make a mess of the entire block. After penetrating three inches, incredibly violent expansion was initiated, which was enough to punch out a ragged hole in our test table despite the surface of the gel remaining intact. The permanent cavity left as a result of the violent yawing and fracturing of the bullet’s base measures about 3×3″, after which the nose and individual fragments go their separate ways to continue wounding on six separate trajectories.
According to the manufacturer, the aluminum nose of the bullet, which stayed completely intact except for some minor scuffing, is expected to penetrate only nine inches. This was consistent with our testing, which found that the nose penetrated about 9″ including some bounceback, which we gave it credit for. The penetration of the other fragments was less consistent in our test, with the least penetrating petal coming in at around 10.5″ with bounceback, and the most penetrating petal measuring a little over 14″. The circular base, which took a slightly upwards but otherwise straight trajectory compared to the rest of the fragments, penetrated exactly 14″.
Total horizontal and vertical spread of the fragments was about 3×4″ respectively.
I’ve also included a gallery below with multiple angles of the gel block for a more detailed evaluation of the bullet’s performance.
The charred black portions of the gel are actually burned due to the rapid expansion and compression of air inside the block, which ignited after the temporary stretch cavity collapsed. Almost all of the bullet fragments were similarly charred.
After studying the gel block, it was brought inside to retrieve the bullet fragments for closer examination. The bullet base split into its five components (the four petals and the base) as designed.
Each of the base fragments differed slightly in size, with sharp edges and a jagged surface where they separated from the base. Just like the preliminary water bucket test, the tip was almost completely free of damage, with only some scuffing and slight charring from the rapid compression of air inside the block’s temporary cavity.
Each of the fragments was individually weighed. The actual weights correspond to what we expected based on the fragments from the water bucket test.
The fragments, including the nose, differed slightly in weight from those recovered after the water bucket test, which highlights what appears to be a manufacturing issue with these bullets leading to high weight variances. Reviews on Lehigh Defense’s own site also note a significant variance in bullet weights in the 78 grain product.
While we weren’t able to weight the bullet before it was fired, the assumption is that the bullet retained either 100%, or close to 100%, of its total weight.
The test results were a bit of a mixed bag. Chronograph results were excellent, as well as the violent transfer of energy from the bullet to the target, but there were some areas which seemed to be lacking compared to the manufacturer’s performance data and our expectations.
Defensive bullets (and their fragments) should penetrate to a minimum of 12″ in ballistics gel to reliably hit vital structures in real world applications. While four out of five of the bullet’s base fragments penetrated to 12″ (with two of them just barely hitting the 12″ mark), one of them fell substantially short, coming in at only 10″ or so. While a larger sample size is needed to definitely speak for the performance of this ammunition, more testing is needed to conclusively evaluate this bullet’s performance as loaded by the manufacturer.
The temporary cavity expansion this bullet creates is absolutely devastating. Because this wouldn’t take place in a live target until the bullet had penetrated skin, muscle, and bone, the potential this has to destroy or disrupt the normal function of vital organs is enormous. By not providing these barriers and only acting as a homogeneous medium which averages the density of the human body, 10% ballistics gel is limited in how accurately it can approximate real world performance. Because it also fractures into multiple fragments which penetrate deep enough to reach vital structures, this bullet has the unique capability to make takedown shots that would have narrowly missed vitals using a traditional expanding bullet. Even though it’s not quite as large as the manufacturer’s claims, the 3×4″ damage cone created by the fragments creates significantly higher probability of a vitals hit than the traditional 0.35″ wound tracks an expanding-style bullet might create. However, I do harbor concerns about this bullet breaking in half after penetrating a barrier, as good self-defense bullets should be barrier blind (see our companion post on 300 Blackout drywall penetration). Although I can’t logically foresee the need for a home owner to shoot a target they can’t even identify through drywall, the FBI has long held that a bullet should be able to penetrate a variety of intermediate barriers and still deliver acceptable terminal performance.
This technology has great potential as a home defense bullet and adds new capabilities to the already capable 300 Blackout round. While I might not immediately throw out my Barnes TTSX bullets and swap them out for these, I am definitely interested to see more testing from other independent reviewers and any street records which may develop in the coming years. Hunters taking deer with this round may also provide insight into performance which may be difficult to discern in artificial mediums like water and ballistics gel.