Published: 2024 | Last updated: June 2026
Introduction
The Lehigh Defense Maximum Expansion (ME), introduced in 2012, fills a distinct role in Lehigh’s lead-free lineup. Where the Controlled Chaos sheds petals while a base continues penetrating, and the Controlled Fracturing fractures at depth, and the CQB completely disintegrates, the Maximum Expansion does none of these. It is Lehigh’s conventional mushroom-expansion design – the bullet expands to a larger diameter through four razor-sharp petals while retaining essentially all of its original weight as a single deformed projectile, similar in principle to how a Barnes TTSX or Hornady GMX mushroom, but with a larger hydraulic cavity engineered for more dramatic expansion diameter.
This makes the Maximum Expansion the most broadly comparable Lehigh design to mainstream monolithic hunting bullets, while retaining two characteristics shared with other Lehigh products: barrier-blind activation (it does not expand on hard barriers, only fluid tissue) and a low minimum activation velocity that extends to subsonic range depending on caliber.
The caliber range is unusually wide for a single bullet line – .224-inch through .452-inch, spanning rifle varmint calibers, standard rifle calibers including 300 Blackout and 308 Winchester, and large pistol calibers including 9mm Luger, 357 Magnum, and .45 Colt. This breadth makes the ME comparable in scope to the Lehigh Defense Controlled Fracturing in terms of caliber coverage, though the two use entirely different terminal mechanisms. Within Lehigh’s broader lineup, the Lehigh Defense Tipped Controlled Chaos and Lehigh Defense CQB round out the full range of fragmentation and expansion philosophies the company offers.
The original article’s claim of “near-100% weight retention” is, notably, more credible than similar claims made about other bullets reviewed in this series – because the ME genuinely is a non-fragmenting, non-disintegrating design. Unlike a bonded lead-core bullet where 90-95% retention is the honest ceiling due to some jacket material loss during expansion, a solid monolithic bullet that mushrooms without fragmenting can legitimately approach 95-99% retention, since there is no separate core to shed and the four-petal expansion typically does not break material away from the bullet.
Disclaimer: Reloading is an inherently dangerous activity. Always consult current published load data from Lehigh Defense at lehighdefense.com before loading any cartridge. Solid copper bullets generate higher chamber pressures than lead-core bullets of the same weight. Never use lead-core load data for the Maximum Expansion. Start at the published minimum charge and work up carefully. The Maximum Expansion requires a minimum impact velocity of 750-1,000 fps depending on caliber for reliable expansion – verify your load achieves this. Never exceed maximum published loads. The information on this page is for educational reference only and does not replace a current reloading manual.
Technical Characteristics
Large hydraulic-cavity hollow-point: The ME’s nose cavity is engineered larger than the cavities found in the Controlled Chaos or Controlled Fracturing, designed specifically to maximize hydraulic pressure buildup on impact and drive aggressive expansion to up to 2x original diameter. The four pre-formed petals split symmetrically and fold outward, creating a wide, flat mushroom face that maximizes the wound channel diameter compared to a more modest 1.5x expansion typical of conventional cup-and-core hunting bullets.
Near-complete weight retention: Because the petals remain attached to the bullet body rather than separating (as they do in the Controlled Chaos), the ME retains essentially all of its mass after expansion. This combines large wound channel diameter with retained mass and momentum – a combination that conventional fragmenting designs cannot offer, since fragmentation by definition sheds material and momentum.
Low activation threshold, subsonic-capable: The ME activates from 750 fps in some calibers up to approximately 1,000 fps in others, depending on caliber and cavity geometry. This is comparable to the Controlled Fracturing‘s subsonic capability but achieved through a different mechanism – large cavity hydraulic expansion rather than pre-stressed delayed fracturing. This makes the ME one of the few monolithic mushrooming designs that reliably expands at subsonic 300 Blackout velocities (approximately 1,000-1,050 fps), a velocity range where most conventional expanding bullets, lead-core or monolithic, fail to expand.
Barrier blind: Like other Lehigh designs, the ME does not expand on hard barriers – brush, light wood, similar obstructions – activating expansion only on fluid tissue contact. This ensures the bullet arrives at the target intact regardless of intervening light cover.
Solid copper, lead-free: Machined or formed from solid copper with no core. Lead-free compliant. Generates higher chamber pressure than lead-core bullets of comparable weight – Lehigh-specific load data is required.
Ballistics and Performance
G1 BCs from 0.150 to 0.350 reflect the range from light rifle varmint weights through heavy pistol-caliber bullets. These are modest figures appropriate to the application – the ME’s design priority is wound channel diameter and weight retention, not aerodynamic efficiency for extended range.
The 194-grain .308-inch subsonic at BC 0.350 and SD 0.292 is the standout rifle variant, specifically engineered for 300 Blackout subsonic hunting. SD 0.292 is high for a subsonic 300 Blackout bullet, providing good post-expansion penetration depth even at the modest impact energy subsonic loads generate. For suppressed 300 Blackout hunters who want a genuinely expanding lead-free bullet at subsonic velocities (rather than the complete disintegration of the CQB or the delayed fracturing of the CF), the ME 194-grain provides conventional mushroom expansion with near-full weight retention – arguably the most straightforward terminal performance concept of any Lehigh subsonic option.
The 175-grain .308-inch at BC 0.350 and SD 0.264 and 110-grain .308-inch at BC 0.300 and SD 0.166 cover 300 Blackout supersonic and lighter 308 Winchester applications respectively. The 110-grain’s low SD (0.166) limits penetration depth, making it most appropriate for smaller deer and hogs at moderate range rather than larger game requiring deep penetration.
The 70-grain .224-inch at BC 0.250 and SD 0.199 is positioned for 223 Remington varmint and predator applications, though the original article’s varmint framing somewhat understates the weight retention advantage here – unlike a true varmint bullet designed to fragment, the ME 70-grain retains its weight and produces a more controlled wound than fragmenting varmint designs, making it equally suitable for predator hunting where some penetration retention is valued.
The pistol caliber variants – 150-grain .355-inch (BC 0.199, SD 0.169) and 220-grain .452-inch (BC 0.184, SD 0.154) – cover 9mm Luger/.357-class and 45 ACP/.45 Colt-class handgun hunting and defensive applications respectively. For hunters using 44 Magnum or 40 S&W revolvers and pistols, Lehigh’s broader catalog includes additional diameter options beyond the ME’s specific .355 and .452-inch offerings.
Accuracy of 0.5-0.8 MOA in rifle calibers is solid for a solid copper monolithic design.
Expert Ballistics Table – Lehigh Defense Maximum Expansion Variants
Data from Lehigh Defense specifications. BCs are G1. Verify current figures at lehighdefense.com. Activation threshold ranges from 750-1,000 fps depending on caliber.
| Diameter (inches) | Weight (grains) | BC (G1) | Sectional Density | Application |
|---|---|---|---|---|
| .224 | 70 | 0.250 | 0.199 | Varmints, predators in 223 Remington |
| .308 | 110 | 0.300 | 0.166 | Deer, hogs in 300 Blackout supersonic |
| .308 | 175 | 0.350 | 0.264 | Deer, hogs in 300 Blackout and 308 Winchester |
| .308 | 194 | 0.350 | 0.292 | Deer, hogs in 300 Blackout subsonic – 750+ fps activation |
| .355 | 150 | 0.199 | 0.169 | 9mm Luger and 357 Magnum hunting/defense |
| .452 | 220 | 0.184 | 0.154 | 45 ACP and .45 Colt hunting/defense |
Comparison Bullets
The ME’s correct comparison set spans both lead-free monolithic hunting bullets and, for its subsonic application, the limited field of subsonic-capable expanding bullets.
The Hornady GMX is the most direct mainstream comparison for the rifle calibers – both are monolithic lead-free designs with conventional mushroom expansion. The GMX achieves BCs from 0.245-0.540, generally exceeding the ME’s 0.150-0.350 range at comparable weights, reflecting the GMX’s polymer tip and more refined aerodynamic profile versus the ME’s open hydraulic cavity. The GMX’s expansion threshold is the conventional 1,800 fps, while the ME’s lower threshold (750-1,000 fps depending on caliber) is the meaningful advantage for subsonic and extended-range applications. For standard supersonic rifle hunting where BC and trajectory matter most, the GMX generally holds the edge; for subsonic or close-range applications where the lower activation threshold matters, the ME is the more capable design.
The Barnes TTSX is the established premium monolithic standard with BCs from 0.295-0.586 and the longest field record of any lead-free hunting bullet. The TTSX’s standard 1,800 fps threshold makes it inappropriate for subsonic use, where the ME has a clear advantage.
The Lehigh Defense Controlled Fracturing is the most relevant within-Lehigh comparison for subsonic and pistol applications, sharing similar caliber coverage and activation threshold range. The key difference is mechanism: the CF fractures at depth into multiple petals with a retained penetrating base, producing a different wound profile than the ME’s single mushrooming projectile. For hunters who want one large wound channel with maximum retained weight, the ME is the choice; for hunters who want a sequential fracture mechanism with a separate penetrating component, the CF is the alternative.
The Nosler E-Tip and Federal Trophy Copper are additional lead-free conventional expanding options, both with higher BCs than the ME at comparable weights but standard expansion thresholds around 1,800 fps, making them inappropriate for subsonic use.
Comparison Table – Lead-Free Mushroom-Expanding Bullets
| Bullet | Diameter Range | Weight Range | BC Range | Activation Threshold | Subsonic Capable | Weight Retention |
|---|---|---|---|---|---|---|
| Lehigh ME | .224-.452 | 70-220 gr | 0.150-0.350 | 750-1,000 fps | Yes (some calibers) | 95-99% |
| Lehigh CF | .308-.500 | 90-300 gr | 0.150-0.450 | 750+ fps | Yes | Partial (fractures) |
| Hornady GMX | .224-.338 | 70-200 gr | 0.245-0.540 | 1,800 fps | No | 95%+ |
| Barnes TTSX | .224-.338 | 50-225 gr | 0.295-0.586 | 1,800 fps | No | 95%+ |
| Nosler E-Tip | .243-.338 | 90-200 gr | 0.300-0.523 | 1,800 fps | No | 95%+ |
Applications and Practical Aspects
Varmints and predators (.224-inch, 70 grains): The 70-grain in 223 Remington provides lead-free expansion with retained weight – a meaningfully different terminal profile than a fragmenting varmint bullet like the Hornady V-MAX. For prairie dog work where fragmentation is desirable for the visual effect and minimal pelt damage doesn’t matter, a true fragmenting design like the Barnes Varmin-A-Tor or Speer TNT is more appropriate. For coyote and predator hunting where some hide preservation matters and controlled mushroom expansion is preferred over explosive fragmentation, the ME 70-grain is a reasonable choice. Hodgdon Varget and Hodgdon H4895 are appropriate for 223 Remington at this weight; for 22-250 Remington with similar weights, the same powders typically apply with appropriate charge adjustments.
300 Blackout supersonic and subsonic (.308-inch, 110-194 grains): This is the ME’s strongest application set. For trajectory data, see the 300 Blackout ballistics guide and the 300 Blackout subsonic loads guide. The 110-grain and 175-grain cover supersonic 300 Blackout hunting with conventional mushroom expansion. The 194-grain subsonic is the standout – one of relatively few genuinely expanding lead-free bullets engineered for suppressed 300 Blackout hunting at 1,000-1,050 fps muzzle velocity. For context on where 300 Blackout sits relative to other close-range cartridges, see the 7.62x39mm vs 300 Blackout comparison. For hunters who want expansion (rather than fragmentation or disintegration) from a subsonic load, the ME 194-grain is among the most appropriate Lehigh options. Hodgdon CFE Blk and Hodgdon H110 cover both supersonic and subsonic 300 Blackout loads. For AR-15 platforms, use CCI No. 41 to prevent slam-fire.
Pistol hunting and defense (.355-inch and .452-inch): The 150-grain .355-inch covers 9mm Luger and 357 Magnum hunting and defensive applications, providing lead-free conventional mushroom expansion as an alternative to jacketed hollow-points like the Sierra Sports Master or Sierra V-Crown. The 220-grain .452-inch covers 45 ACP and .45 Colt for similar applications, particularly relevant for revolver hunters using .45 Colt for deer and hog hunting at close range. Hodgdon Titegroup and Alliant Power Pistol are standard powders for 9mm Luger; Hodgdon H110 and Alliant 2400 for 357 Magnum and .45 Colt at full power.
Reloading
The ME requires Lehigh Defense-specific load data given the higher pressure characteristics of solid copper construction across both rifle and pistol applications.
Primers: For 223 Remington and 300 Blackout rifle applications, standard small rifle primers CCI 400 and Federal 205 are appropriate, with CCI No. 41 required for AR-15 platforms. For pistol calibers, standard small or large pistol primers depending on caliber – CCI 500 or Federal 100 for 9mm Luger, CCI 300 or CCI 350 for 357 Magnum and .45 Colt. Winchester WSP is a standard alternative small pistol primer for 9mm Luger loads.
Cases: Standard brass appropriate for each caliber – Lapua and Starline for 300 Blackout, and Starline or Winchester for pistol calibers.
Seating depth: For rifle applications, start at 0.050-0.100 inches off the lands – solid copper requires more freebore than lead-core. For pistol applications, use Lehigh’s published COAL specifications, as magazine length and cylinder constraints typically drive seating depth more than throat engagement.
Velocity verification: Before finalizing a hunting load, particularly for subsonic 300 Blackout, confirm via chronograph that your load achieves the minimum activation velocity (750-1,000 fps depending on caliber) at your maximum intended hunting distance.
Powder Selection by Application:
| Application | Caliber | Bullet Weight | Recommended Powders |
|---|---|---|---|
| Varmints/predators | 223 Rem | 70 gr | Hodgdon Varget, Hodgdon H4895, Hodgdon CFE 223 |
| Deer/hogs supersonic | 300 Blackout | 110-175 gr | Hodgdon CFE Blk, Hodgdon H110, Accurate 1680 |
| Deer/hogs subsonic | 300 Blackout | 194 gr | Hodgdon CFE Blk, Hodgdon H110, Winchester 296 |
| 9mm hunting/defense | 9mm Luger | 150 gr | Hodgdon Titegroup, Alliant Power Pistol, Hodgdon CFE Pistol |
| 357 Mag hunting | 357 Magnum | 150 gr | Hodgdon H110, Alliant 2400, Hodgdon Lil’Gun |
| 45 Colt hunting | 45 Colt | 220 gr | Hodgdon H110, Alliant 2400, Federal 150 |
Reloading Parameters Summary:
| Parameter | Guideline |
|---|---|
| Neck tension | 0.002-0.004 inch interference |
| Seating depth – rifle | 0.050-0.100 inch off lands |
| Seating depth – pistol | Lehigh published COAL; cylinder/magazine constraints |
| Minimum activation velocity | 750-1,000 fps depending on caliber – verify at impact |
| Load data source | Lehigh Defense at lehighdefense.com |
| Weight retention | 95-99% typical (genuine, non-fragmenting design) |
Frequently Asked Questions
Q: How is the Maximum Expansion different from the Controlled Chaos?
A: The Controlled Chaos sheds its front petals entirely on impact, separating them from the bore-diameter base, which then continues penetrating as a separate component. The Maximum Expansion’s four petals remain attached to the bullet body, folding outward into a mushroom shape rather than separating – the bullet stays together as a single deformed projectile. This means the ME retains nearly all its original weight (95-99%) as one continuous mass, while the Controlled Chaos’s total recovered weight is split between the petals and the base. For hunters who want one wide wound channel with maximum retained momentum reaching the vitals, the ME’s single-mass mushroom is the more conventional and arguably more predictable terminal profile. For hunters who specifically want the dual fragmentation-plus-penetration effect, the Controlled Chaos is the alternative.
Q: Is the “near-100% weight retention” claim believable, given that other bonding claims in this bullet category have sometimes been overstated?
A: Yes, with the caveat that it applies specifically to this non-fragmenting design. The skepticism warranted for “bonded” claims on jacketed lead-core bullets (where 90-95% is the honest ceiling because some jacket material is typically lost during expansion) doesn’t directly apply here, because the ME is a solid monolithic bullet with no separate core to shed. When a solid copper bullet mushrooms via four-petal expansion without those petals breaking off, there is genuinely very little material to lose. The claim is more credible for this specific construction type than equivalent claims for plated or bonded lead-core designs.
Q: Can the Maximum Expansion be used for 300 Blackout subsonic hunting, and how does it compare to the Controlled Fracturing for that application?
A: Yes, the 194-grain .308-inch variant is specifically engineered for this. Compared to the Controlled Fracturing 198-grain subsonic option, the two represent different terminal philosophies at the same velocity range. The ME mushrooms into a single wide projectile with near-full weight retention. The CF fractures into multiple petals at depth with a separate retained base. Both are viable lead-free subsonic hunting options; the choice comes down to whether you prefer a single expanded wound channel (ME) or a fracture-plus-penetration sequence (CF). Neither has overwhelming field-tested superiority over the other at the time of writing – both are specialized products with limited published third-party load data, and direct hunter comparisons are valuable for the broader community.
Q: Why does the original article frame the 70-grain .224-inch as a varmint bullet when it retains weight rather than fragmenting?
A: This is a fair point of confusion to clarify. True varmint bullets like the Hornady V-MAX are specifically designed to fragment completely on impact, producing the dramatic surface explosion effect prairie dog hunters favor. The ME 70-grain instead mushrooms and retains weight – a controlled-expansion profile more similar to a hunting bullet than a true fragmenting varmint design. This makes it less suited to prairie dog work (where complete fragmentation is the desired effect) and better suited to coyote and predator hunting, where retained weight and a controlled wound channel without excessive pelt damage may be preferred. The original article’s varmint framing somewhat undersells what this bullet actually does well.
Q: Is the Maximum Expansion appropriate for deer hunting at standard rifle velocities, not just subsonic 300 Blackout?
A: Yes – the ME’s low activation threshold (750-1,000 fps) means it will reliably expand at standard supersonic rifle velocities as well, which are well above the minimum threshold. The 110-grain and 175-grain .308-inch variants in 300 Blackout supersonic or comparable applications provide conventional mushroom expansion at the velocities those cartridges produce. The bullet’s design advantage at subsonic velocities does not come at the expense of performance at higher velocities – it simply extends the reliable activation range further down than most conventional designs.
Q: How does the .452-inch 220-grain variant compare to standard .45 Colt hunting loads?
A: For revolver hunters using .45 Colt for deer and hog hunting, the 220-grain ME provides lead-free conventional expansion with retained weight – a meaningful alternative to lead semi-wadcutter or jacketed hollow-point designs commonly used in heavy .45 Colt hunting loads. SD 0.154 is modest, reflecting the wide bullet diameter relative to weight typical of large-bore pistol calibers, but at the close ranges typical of revolver hunting (inside 50-75 yards), the combination of wide expansion and retained weight should provide adequate terminal performance on deer-sized game. As with all Lehigh products, use Lehigh’s specific .45 Colt load data rather than extrapolating from lead bullet data given the pressure differences in solid copper construction. The Lehigh Defense Wide Flat Nose is another option within the brand for hunters who want a different .45 Colt terminal profile.
Conclusion
The Lehigh Defense Maximum Expansion is Lehigh’s conventional mushroom-expansion design, distinguishing it from the fragmentation-based Controlled Chaos, Controlled Fracturing, and CQB elsewhere in the lineup. Its combination of wide expansion diameter, near-complete weight retention, barrier-blind activation, and a low activation threshold extending to subsonic velocities makes it a genuinely versatile lead-free option spanning rifle varmint calibers through large pistol calibers.
The 194-grain .308-inch subsonic variant is the standout product in this lineup – one of relatively few genuinely expanding lead-free bullets specifically engineered for suppressed 300 Blackout hunting.
Choose the Maximum Expansion if: you hunt with suppressed subsonic 300 Blackout and want conventional mushroom expansion rather than fragmentation; you hunt deer or hogs with 357 Magnum or .45 Colt revolvers and want lead-free conventional expansion; you want maximum wound channel diameter with near-complete weight retention in a lead-free design; or you hunt in California or another lead-restricted jurisdiction across multiple calibers from rifle to pistol.
Choose something else if: you want the highest available BC in a lead-free monolithic for standard supersonic rifle hunting – the Barnes TTSX or Hornady GMX generally exceed the ME’s BCs at comparable weights. If you want the dual fragmentation-plus-penetration mechanism specifically, the Lehigh Defense Controlled Chaos or Controlled Fracturing provide that alternative terminal profile. For true varmint fragmentation rather than controlled expansion, use a dedicated fragmenting design like the Hornady V-MAX. For pistol defensive applications specifically, the Lehigh Defense Xtreme Defense is an additional within-brand option. If lead is not a concern and you want a premium bonded rifle bullet, the Federal Trophy Bonded is worth comparing.
Disclaimer: Reloading involves inherent risks. The Maximum Expansion is a solid copper bullet that generates higher chamber pressures than lead-core bullets – never use lead-core load data. Use Lehigh Defense-specific data from lehighdefense.com. Verify that impact velocity at your maximum hunting range exceeds the minimum activation threshold for your specific caliber (750-1,000 fps). Start below minimum charges and increase gradually. Wear eye protection at all times. The author and myreloading.com are not responsible for injuries or property damage from reloading or shooting handloaded ammunition.
Have you hunted with the Lehigh Defense Maximum Expansion? Leave a comment with the details: diameter, weight, cartridge, game, range, shot angle, and what you observed. Subsonic 300 Blackout hunting accounts with the 194-grain are especially valuable given how few field reports exist for this specific application. Comparisons against the Controlled Fracturing at the same velocity would also be useful for other hunters weighing the two options.
Editorial note: Originally published 2024, revised June 2026. The update added detailed explanation of how the Maximum Expansion’s single-mass mushroom mechanism differs from the petal-separation mechanism of the Controlled Chaos and the delayed-fracture mechanism of the Controlled Fracturing – clarifying that this is Lehigh’s conventional expanding design, not a fragmenting one. Applied appropriate scrutiny to the near-100% weight retention claim, noting it is more credible here than similar claims for bonded lead-core bullets given the genuinely non-fragmenting solid construction. Reframed the 70-grain .224-inch from “varmint bullet” to predator/coyote bullet given that it retains weight rather than fragmenting. Highlighted the 194-grain subsonic .300 Blackout variant as the lineup’s standout application. Added FAQ section covering six common questions. Applied full internal linking throughout.
Introduction
Discover the Lehigh Defense Maximum Expansion (ME), a lead-free bullet engineered for hunters who demand ultimate wound channel creation and controlled penetration. Launched by Lehigh Defense in 2012, based in Quakertown, Pennsylvania, the Maximum Expansion meets lead-free regulations in areas like California with its solid copper construction.
Renowned for its maximum expansion and large wound channels, the Maximum Expansion delivers devastating terminal performance, making it a top choice for ethical hunters targeting medium game. Its innovative design ensures consistent results across varied hunting scenarios, from close-range brush to moderate distances.
- Caliber Range: Available from .224 to .452 inches, supporting cartridges like .223 Remington, .300 Blackout, .308 Winchester, 9mm Luger, .357 Magnum, and .45 Colt.
- Weight Options: Spans 70 to 220 grains, with key variants like 70-grain .224, 110-grain .308, and 194-grain .308 subsonic.
- Hunting Focus: Optimized for massive wound channels with controlled penetration, ideal for medium game and self-defense scenarios.
Technical Characteristics
The Lehigh Defense Maximum Expansion is crafted for hunters seeking massive energy transfer and reliability. Its solid copper construction and unique expansion make it a standout in the field.
- Solid Copper Construction: Lead-free design ensures compliance with regulations, with near-100% weight retention after expansion, preventing core-jacket separation.
- Expansion Design: Hollow-point cavity expands via hydraulic energy in fluid mediums, achieving up to 2x diameter with 4 razor-sharp petals for maximum wound channels.
- Barrier Blind: Does not expand on dry mediums like wood or bone, activating only on fluid for controlled performance and reduced over-penetration risks.
- Velocity and Range: Optimized for muzzle velocities of 750-3,000 fps, including subsonic, effective to 300+ yards with good stability.
- Reduced Fouling: Solid copper reduces barrel fouling by 15-20% compared to lead-core bullets, extending cleaning intervals.
Reloading requires precision, using standard dies and SAAMI-compliant COAL to manage pressures. Maintain case neck tension (0.002-0.004″) for optimal accuracy, as the Maximum Expansion’s durable construction suits rugged hunts but demands careful load development.
Ballistics and Performance
With G1 BCs ranging from 0.150 to 0.350, the Maximum Expansion offers solid stability and wind resistance for its class, supported by sectional density for effective penetration post-expansion. Field tests show a 110-grain .308 Maximum Expansion achieving 0.5-0.8 MOA at 300 yards with ES/SD under 15 fps from a 1:10 twist barrel. The 70-grain .224 is ideal for varmints, while the 194-grain .308 subsonic excels for close-range medium game, delivering energy to 200 yards.
The Expert Ballistics Table below lists key Maximum Expansion variants from Lehigh Defense specifications, sorted by diameter then weight. BCs are G1; verify on Lehigh’s site for updates.
| Diameter (inches) | Weight (grains) | Ballistic Coefficient (BC) | Sectional Density |
|---|---|---|---|
| 0.224 | 70 | 0.250 | 0.199 |
| 0.308 | 110 | 0.300 | 0.166 |
| 0.308 | 175 | 0.350 | 0.264 |
| 0.308 | 194 | 0.350 | 0.292 |
| 0.355 | 150 | 0.199 | 0.169 |
| 0.452 | 220 | 0.184 | 0.154 |
Groups of 0.5-0.8 MOA achievable; excels to 300 yards with proper shot placement.
Comparison Bullets
The Maximum Expansion competes with Lehigh Defense Controlled Fracturing (pre-stressed fragmentation) and Hornady GMX (monolithic copper). Its BCs (0.150-0.350) are comparable to Controlled Fracturing (0.150-0.450) but lower than GMX (0.245-0.540) in some weights, offering larger wound channels. The Maximum Expansion expands to 2x diameter at 750 fps, achieving 10-15% more wound volume than GMX but with limited penetration unlike Controlled Fracturing. Against Controlled Fracturing 198gr .308, the Maximum Expansion 194gr .308 creates wider channels at subsonic; versus GMX 139gr 6.5mm, it expands 10% larger. Advantages: lead-free, max wound, barrier blind. Drawbacks: velocity-sensitive, higher cost ($0.50-$1.00 per bullet).
| Bullet | Diameter Range (inches) | Weight Range (grains) | BC Range | Key Feature |
|---|---|---|---|---|
| Lehigh Defense Maximum Expansion | 0.224-0.452 | 70-220 | 0.150-0.350 | Hydraulic expansion, solid copper |
| Lehigh Defense Controlled Fracturing | 0.308-0.500 | 90-300 | 0.150-0.450 | Pre-stressed fragmentation, solid copper/brass |
| Hornady GMX | 0.224-0.338 | 70-200 | 0.245-0.540 | Polymer tip, monolithic copper |
Field reports show Maximum Expansion outperforming Controlled Fracturing in wound volume and matching GMX in penetration consistency for medium game hunting.
Applications and Practical Aspects
Ideal for hunting:
- 70gr .224 for varmints;
- 110-175gr .308 for deer and hogs;
- 194gr .308 subsonic for close-range medium game;
- 150-220gr .355-.452 for self-defense or medium game.
Delivers 0.5-0.8 MOA in tuned rifles, ideal for ethical kills.
Reloading
- Load Data: Refer to Lehigh’s load data library or website for Maximum Expansion-specific data, as the solid copper design generates higher pressures than lead-core bullets.
- Starting Charges: Begin 5-10% below maximum loads for comparable lead bullets to avoid over-pressure; increase gradually while checking for pressure signs.
- Seating Consistency: Ensure precise seating depths (0.010-0.050″ off lands) to maximize accuracy, as the Maximum Expansion’s bearing surface is sensitive to inconsistencies.
- Crimp Application: Apply a light to medium crimp on the cannelure for secure bullet retention, particularly in semi-auto or high-recoil rifles, ensuring reliable feeding.
- Barrel Twist Compatibility: Match barrel twist rate to Maximum Expansion weight (e.g., 1:10 for 110gr .308, 1:7 for 194gr .308) for proper stabilization and optimal accuracy.
- Velocity Check: Chronograph to confirm velocities above 750-1,000 fps for reliable expansion, targeting extreme spreads under 15 fps.
- Storage: Store in sealed containers to protect from moisture; suitable for all hunting applications per design.
Conclusion
Lehigh Defense Maximum Expansion is an innovative lead-free hunting bullet, blending maximum expansion for wound channels with controlled penetration. Its barrier-blind design and accuracy make it ideal for hunters in lead-restricted areas or pursuing medium game. Visit official website.
