F A Q 's
Copper Bullets
1 - What are the advantages of OEP copper bullets?
- Made from pure copper which is more pliable yet tougher than jacketed lead bullets
- Full expansion (100 – 120%) at hunting distances – maximising shock potential
- Deadly from the end of the muzzle to the 1,600 fps minimum expansion velocity threshold
- Reliably and predictably expands on ‘soft’ game
- Able to smash through thick hide, shoulder tissue and heavy bone on tough game – shoulder and raking shots are no longer a problem
- Retain more than 95% of its original weight to provide maximum momentum, a requirement for deep penetration
- Delivers the best terminal performance possible
- CNC machined to 1 micron tolerance for ultimate precision
- No batch to batch variations in dimensions
- Australian made with continuous reliable supply
2 - OEP bullets are lighter than jacketed lead bullets, is there a reason?
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Displacement is more important than bullet weight, and retained bullet weight = momentum is of greater importance the initial bullet weight.
OEP were designed from the ground up to have maximum structural integrity (retained weight) and expansion and not to match conventional bullet weights. There is no downside to this approach and only positive gains for the shooter. OEP will retain at least 95% of their original weight and often up to 99%, whereas jacketed lead bullets typically lose 50% or more of their weight on impact. So in the real world OEP will more than likely outperform conventional bullets during flight and post impact on game. A quick comparison using Quick Load (QL) to generate the terminal ballistics for an OEP 6.5 mm – 113 gr BBT and Hornady 142 ELDM from a 6.5 Creedmoor with a 24” barrel demonstrates there is no downside in using a lighter, faster and tougher bullet at responsible hunting ranges. Lighter bullets also generate less recoil!
Note: these loads are max loads and set for a Zero of 200 yards.
ELDM 140 BC .646 MV 2765 fps 400 yards 600 yards Drop -21.20 -70.74 Velocity 2221 fps 1978 fps OEP 113 BBT BC .469 MV 3064 fps Drop -18.28 -63.20 Velocity 2296 fps 1958 fps
3 - Outer Edge bullets are lighter so is less muzzle energy an issue?
- Muzzle energy and velocity have been the two benchmarks that most rifle cartridges are assessed on. However, this approach is flawed and creates misleading data if bullet performance (structure) and momentum aren’t added to the equation. Let’s say a 150 grain jacketed lead bullet is fired from a 30-06 and on impact breaks up and loses 50% of its weight. No matter how high the muzzle energy was, the bullet has lost a large percentage of its weight, which reduces momentum, the key factor for bullet penetration required to reach vital organs and create as much tissue damage as possible. Outer Edge won’t break up and will drill deep to deliver emphatic kills. Bullet terminal performance is a lot more than just numbers and more about what happens in the real world, isn’t that what all hunters need?
4 - There have been issues with some long range bullets blowing up on game at close ranges. Does Outer Edge have the same issues?
- No. Jacketed lead bullets can’t match the structural integrity of copper. Certainly there are some tough jacketed lead bullets on the market but these are primarily designed for close range hunting. There are also very thin jacketed bullets designed for extended long ranges but will break up and fail at close range. Outer Edge bullets will expand and hold together from the end of the muzzle out to the 1,600 fps velocity threshold.
5 - Some copper bullets pin hole game, does Outer Edge have the same problems?
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No. Jacketed lead bullets are universally swaged, but this process greatly work hardens copper, introducing hardness and brittleness to the equation. The original Gen 1 copper bullets required very high velocities to expand and if the velocity was too high, the petals would break off; too low, and they wouldn’t expand at all, thus producing the dreaded pin holing scenario.
Outer Edge bullets are turned on a specialised CNC machine with copper of a specific grade and temper which is not changed by the manufacturing process. The aggressive ogive (nose shape) profile of Outer Edge bullets improves ballistic efficiency and at the same time allows vastly improved expansion control. Outer Edge bullets will open up and expand on light bodied game out to the 1,600 fps expansion thresh hold and yet still hold together on tough game. This is a major challenge for jacketed lead bullets.
6 - Are copper bullets more expensive?
- OEP are comparable and in some cases cheaper in pricing to Premium Bonded bullets. No matter what bullet is used, consider this. If $1000’s has been invested in a rifle, scope, reloading gear and travel and your bullet of choice fails, then that’s expensive. So if the bullet you chose can’t reliably perform at both close and long distances from every shot angle, that is a major performance discount. In these situations, cheap in price becomes costly in performance. So if you are a hunter who demands peak performance, then the price for premium bullets shouldn’t be a consideration. Outer Edge Projectiles cost less than imported copper hunting bullets.
7 - Supply and availability
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Outer Edge don’t have the supply problems like USA manufactures. Outer Edge has invested in developing a nimble and responsive supply chain that is much faster than any imported product supply. If a retailer doesn’t have the bullet required, then Outer Edge can usually supply with 5 to 10 working days. Outer Edge are 100% Australian made and has been in business since 2012 and still going strong.
Please don’t hesitate to contact us if you require assistance with finding or purchasing bullets.
8 - Don’t copper bullets foul more?
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Yes and No.
Fouling is common and problematic with raw copper bullets that aren’t coated. However, Outer Edge bullets are coated with a proprietary non-toxic safe to handle dry lubricant that reduces fouling to a very low level. Shot start pressures are reduced approx. 30%, whilst maintaining SAAMI/CIP standards for bullet diameter. The overall benefit is less cleaning, less chemicals and less wasted time and cost.
9 - Will the coating build up in my barrel?
- No. Some of our competition shooters clean their barrels every 800 rounds, without any deterioration in accuracy. However, Outer Edge strongly recommends rifles are cleaned for long term storage, regardless of how many shots have been fired, as even stainless steel barrels rust.
10 - Can I achieve longer barrel life using Outer Edge?
- Outer Edge Projectiles have decreased friction and extended barrel life is highly probable. However, barrel life is more dependent on how it is used, i.e. how many and how quickly shots are fired and how rapidly the barrel heats up. The benefit with Outer Edge Projectiles is that copper’s heat conductivity is approximately four times that of steel, which means that much of the heat generated by friction is transferred to the bullet instead of the barrel. Traditional jacketed lead bullets do not conduct heat near as well. Outer Edge bullets will measurably exhibit significantly less barrel heat than jacketed lead bullets.
11 - The question of copper vs lead bullets and consumption of the wild harvest
Bullets that expand rapidly without exiting are usually jacketed lead products. As most shooters in Australia at least, are culling rather than harvesting animals for consumption, so the lead issue is largely irrelevant in this application. For those of us who consume our harvest, it would be of great surprise to learn just how far lead particles can spray into a seemingly unaffected part of a carcass. There are many graphic and scientific documents to be found on the web exploring this issue, and the implications can be disturbing. Lead contamination of course does not occur with OEP’s copper Hunting bullets. A comforting thought for those of us who really enjoy our venison! For more information on this subject, visit www.dec.ny.gov/outdoor/48420.html
Target Projectiles
Transonically tuned for ultra long range precision
Outer Edge precision CNC copper bullets are extremely accurate over distances that challenge traditional high BC bullets. Most high BC bullets are subject to enormous destabilisation as they transition from supersonic to subsonic flight caused by only slight variations in jacket thickness and meplat or tip, including polyoxymethylene and phenylisocyanate copolymer.
Being CNC from a solid piece of copper, Outer Edge Target bullets wont spin out of balance and have been designed, engineered and tested to be as stable as possible to deliver tight groups right through the transonic zone out to ranges well beyond.
What advantages do OEP Target bullets offer?
OEP bullets are precision CNC turned copper projectiles delivering the following benefits.
- Micron dimension tolerances
- Consistent dimensions from bullet to bullet and batch to batch
- No variation in the base to ogive measurement
- X fine point meplat increases BC – no additional meplat trimming required
- Superb accuracy and transonic stability
- Unlike US bullet makers, OEP offer an ongoing reliable supply
- Higher velocities typically achieved from lighter, magazine fed OEP bullets outweigh any difference in BC when compared to traditional bullets.
- It doesn’t take much velocity to trump BC in terms of better wind bucking ability and trajectory. Use ballistic software to compare
- The single shot bullet range (indicated by #) BC’s are amongst the highest of any commercial bullets in the same weight class. Often exceeding the BC’s of much heavier bullets of traditional designs
- OEP deliver the double bonus of both higher velocity and BC! Do the maths.
- OEP Target Bullets are specifically designed to match barrel twist rates
- Ideal Shot Start Initiation Pressures (SSIP’s) producing consistent ignition — fundamental in achieving the best possible accuracy
- All OEP bullets have an Sg of 1.5 or greater when used in conjunction with the recommended barrel twist. Calculations are based on the universal standard for air pressure; sea level -1013 mb @ 15° C.
- OEP bullets are coated with an advanced proprietary dry lube coating that (unlike moly) is easy to remove when cleaning. It is non-corrosive with a low coefficient of friction; keeping your barrel cooler and cleaner for longer. Testing to date demonstrates longer shot strings are now possible under competition conditions. Cold bore and group consistency is greatly improved.
Miscellaneous
Things to Know about Copper Bullets
1. Copper Bullets and Barrel Matching
As a general rule, there is an ideal copper bullet option for just about every modern cartridge and commercially available rifle currently on the market. There are just two basic principles to keep in mind. Firstly, match your bullet to your barrel twist rate. Secondly, use only conventional or ‘Ratchet’ type land configurations. Copper bullets and the much less common polygonal rifle lands are like spark plugs in a diesel, they just don’t go together.
2. Weight vs displacement
There are a few basic principles that separate copper from jacketed lead bullets. The most obvious one is that copper is approximately 20% lighter, so if you have two bullets, identical by external measurement, they will have the same displacement, but if one is a copper bullet and the other, a jacketed lead product, the copper bullet will be 20% lighter: so, for a working example, a 125 grain copper bullet has a similar displacement to a 150 grain jacketed lead bullet. When it comes to hunting, it is material displacement in the right location that does the damage, not bullet weight.
3. When lighter is heavier
Counterintuitively, lighter copper bullets can be heavier than equivalent displacement jacketed lead bullets when they are doing the job. Most jacketed lead bullets are not core bonded, and typically lose 75% or more of their mass on impact. Core bonded jacketed lead bullets in modern cartridges will generally lose around 25% of their weight on impact. Outer Edge Projectile copper bullets will generally lose less than 2% of their mass when the job is done. So an Outer Edge bullet that started out as a 125 gr specimen now weighs 123 grains. A core bonded jacketed lead bullet that started out at 150 gr, now weighs in at 113 gr at best, and a non-core bonded example is considerably less. Because copper bullets expand, rather than fragment, and maintain mass; they penetrate straight and deep and are usually able to reach the vital organs required for humane destruction from just about any angle. This is something a fragmenting bullet simply cannot achieve.
Lighter bullets also faster, generate less recoil and are more pleasant to shoot.
4. How copper hunting bullets work
Some copper bullet manufacturers design their bullets such that the petals are likely to break off, supposedly creating a larger shrapnel based wound channel. Once separated from the main body however, these so called ‘radiating petals’, which have a mass similar to an air rifle petal, do not drive out into the medium, but only travel as far as the temporary wound cavity vacuum will allow, which is not very far, usually about 50 mm. We are talking about flesh and bone here, not the far more favourable 10-11% ballistic gelatine designed to emulate human resistance for military and law enforcement application.
Outer Edge Projectiles on the other hand, are designed for full mushroom type expansion with maximum weight retention.
It is important to understand that the shock wave created by a bullet, any bullet, is the square of the frontal area of the main body. So a bullet that expands by more than 100% and maintains its mass will create a broad, deep wound channel, giving the hunter the greatest flexibility in shot options for a humane kill. It is vital organ destruction that kills; it’s as simple as that. Whether the bullet stayed inside or went straight through is pretty much irrelevant. If the vital organs have been destroyed, nothing will go very far. If the vital organs were not destroyed, it is again a moot point.
How many 22 rimfire bullets have you ever found in rabbits? Not many I’ll wager.
5. Copper Bullets aren’t all the same: Evolution of the Copper Bullet
Copper bullets are almost as many and varied as motor cars, and to lump them all together into one expectation bundle is likely to be misleading, if not dangerous.
Copper bullets are usually lathe turned, rather than swaged the way jacketed lead bullets are. Turning allows significant latitude in design options that simply can’t be achieved using the swaging process.
But first, a brief history:
First generation designs, some of which are still currently available, were rather reminiscent of early lead projectiles of 150 years ago; i.e. they have a multiband configuration designed to allow flexibility in seating depth. The machinery of 50 years ago required a hard temper copper to allow acceptable machining, and the bullets were often undersized to keep pressures reasonable.
First generation designs quickly demonstrated a number of performance short comings. Being fairly hard, they had to be driven fast to expand, but they could also be brittle, so if impact velocities were too high, the petals would break off; too slow – and they wouldn’t expand at all. This, along with the multi band design, significantly increased drag, limiting effective hunting range. Further, undersized bullets were often challenging to obtain accuracy in some commercially generous barrel dimensions; and tight bores would send pressures soaring. Then there was the issue of barrel fouling. Not ideal.
Second Generation copper bullet designs have obviously sought to address all these short comings, and have been very successful in doing so. These advancements have only been made possible through substantive recent developments in modern manufacturing over the last 20 years. These advancements include material tempering for managing ductility; high speed – exceptionally high tolerance/high precision – fully automated CNC machinery – specifically designed to machine copper and major advancements in antifriction coatings.
Today’s second generation copper bullets can now be made to expand at low velocities, down to 1,600 fps, maintain 98%+ weight retention (in other words, fully expand without fragmentation) and extend effective ranges difficult to compete with by any comparison. This class of bullet meets the SAAMI/CIP size and pressure standards required for safe and consistent ignition using common reloading practice.
Gone is the multi square band system, with BC’s being generally higher than their predecessors, including jacketed lead bullets, in a direct comparison for calibre and weight.
Indeed, second generation copper bullets are setting new standards in many areas, by allowing changes in bullet shape that cannot be replicated in the swaging process. This opens up new areas that were previously challenging, such as tuning a bullet’s performance over its entire flight path.
How to Load Copper Bullets (in order of importance)
1. Match your bullet twist recommendation to your barrel’s twist;
As with all bullets, the first choice to make is to match your bullet selection to your barrel’s twist rate. This is very important. A barrel with a fast twist can handle all well-made bullets, but a barrel with a slow twist can only handle lighter, shorter bullets.
This is a function of the bullet’s weight/calibre/length/twist ratio and not weight in isolation.
Remember, the lower the number, the faster the twist; so a 1 in 7” twist barrel does one full rotation in 7”. A 1 in 12” will do one rotation in 12”, and is therefore longer and slower.
2. Set your free-bore bullet jump
For the most flexible, accurate and consistent loads, most bullets, but especially copper bullets like a longer jump than is commonly expected. A jump of 0.040” – 0.060” or 1 mm to 1.5 mm is the happy place, with 0.050” or 1.25 mm a great place to start. Longer jumps may prove to be successful, but shorter jumps very rarely do.
This arrangement is also less sensitive to changes in temperate and chamber throat erosion. As a general rule, chamber throats will wear at a rate of around 0.005” per 100 rounds for uncoated bullets, whilst coated bullets will wear at a slower rate, reducing the need to constantly chase the lands.
Keep in mind that the main reason to set your bullet jump first, is that it has a big influence on the cartridge case capacity. Once the jump is set, the case capacity is established, and we can then start developing the powder volume relationship.
3. Powder Charge and Primer suggestions
Because copper bullets are 20% lighter for the same displacement, taking up different case capacity ratios, you may find that a different powder selection and charge is recommended to those suggested for jacketed lead bullets. Always follow the manufacturer’s recommendations for their product as your starting point for your component selection, and charge weights. Minor adjustments should only be based on variant seating depths and resultant case capacities. It is also wise to retest your loads when changing powder batches. Whilst today’s powder production standards are very good, minor variations can occur from batch to batch.
Outer Edge Projectiles have a load data table available on the website. If your cartridge is not listed, please ring for assistance.
4. Use only one Brand of Case and do not mix!
The volumetric case capacity for any cartridge will often differ from brand to brand. As such, a load that works really well in one brand, may not work at all in another, and it all comes down to the difference in case capacity and finding that sweet spot we call the nodal point. In some brands, case capacity may even vary from batch to batch, so be careful. It always pays to check! All Outer Edge Projectile load data is based on a nominated brand and case capacity. Variations to these standards will require minor adjustment accordingly.
5. Use the best gear you can afford
Do it right, and do it once. Quality scales, calibrated micrometers and Vernier’s, press and die setup ups will all reduce error and improve outcomes. Given the extremely tight tolerances of second generation copper bullets, ogive comparators are considered unnecessary.
Copper Bullets on Steel Plates
The commonly held paradigm is that copper bullets are more likely to ricochet of steel plates. This is simply not the case with second generation copper bullets.
On mild steel, a jacketed lead bullet will either penetrate, splatter or deflect, depending on the calibre, distance and velocity. A copper bullet will skin form a jester’s crown and alloy itself, bonding to the steel at close range.
On hard surfaces like Bisalloy 500, a copper bullet will flatten its nose, like a politician’s dog chasing a parked car – and literally drop to the ground, even at relatively low velocities. A jacketed lead bullet will either splatter at high velocity, or deflect at low velocity.
What are Outer Edge Projectiles coated with?
An advanced proprietary dry lubricant. We DO NOT use molybdenum disulphide (ms2) as it can build up in the barrel and be difficult to remove. Our product is not toxic, is very easy to clean out and will not harm your barrel.
It reduces Shot Start Initiation Pressures (SSIP) in line with SAAMI/CIP recommendations, and further reduces throat wear.
Do I need to use a special cleaning product when using Outer Edge Bullets, what do you recommend?
Because Outer Edge bullets are coated, most commercial cleaning products will work well if they have both a powder and copper removal component, but we particularly like the Patch Out and M98 products. The most important objective is to remove the carbon as carbon is one of the hardest materials in existence. It is carbon residue under heat and pressure that does much of the grinding damage we call throat erosion, reducing barrel life.
Are there alternative materials other than copper that would make a suitable bullet material alternative – like brass products?
Bullet materials need to have certain qualities to perform at their best, and each material, even when it excels in one area, may be compromised in another. The question is, are all the qualities within acceptable limits? Examples of such qualities are: machinability, specific gravity, durability/stability, ductility, hardness, toughness, toxicity, cost and availability – to name just a few.
In our view, copper, despite its machining challenges, is by far the best material to use for bullet manufacture from a ballistic point of view, at least in the civilian hunting and target shooting context. The only viable alternatives are extremely high percentage copper alloys. Brass in its various forms might be easy to machine, but is simply too hard and too light for anything other than short range, or specialty application.
I was once asked whether gold or silver would be a suitable substitute for lead in cup and core application. All I say to that is: ‘I’m available for adoption’!
Copper bullets and terminal hunting performance
Many of these issues have already been discussed, but some of the biological response mechanisms need to be understood to get a more complete handle on the situation.
Some species are more or less susceptible to biological shock than others.
Humane hunting outcomes can only be universally guaranteed through massive destruction of vital organs, specifically the brain, spine, heart and lungs. Destruction of other vital organs will certainly be fatal, but may not be within an acceptable timeframe.
Brain and spine shots unquestionably produce instantaneous results, but these are relatively small targets and may be problematic on some species like buffalo where the brain is well protected.
The heart and lungs are much larger and safer targets at longer distances; so let’s consider them for a moment.
The heart is a four chambered pump. It is either full, empty, filling or emptying. Now imagine a balloon. Blow up the balloon and prick it with a pin – the result is spectacular. Poke a hole in a balloon prior to inflating however, and it is surprisingly possible to substantially inflate the balloon, despite the leak. The heart and lungs will respond in similar fashion. This explains why a sometimes well placed shot to the heart or lungs alone will see an animal momentarily drop on impact only to regain its composure and make good its escape.
Now, when we squeeze the trigger, it is impossible to know at what stage of inflation the heart and lungs are in on impact. Whilst this is so, the lungs do surround the heart in the bottom third of the thoracic cavity, and it is most unlikely that both the heart and the lungs will be at the bottom stage of the inflation cycle at the same time. This area is a smaller target than a high lung shot, requiring more careful shot placement, but any impact here will result in a very quick outcome. The only question a hunter has to ask is whether the chosen cartridge and bullet selection is capable of reaching and destroying the vitals from the available angle. As previously discussed, this is more likely with a properly structured bullet.
What about Sectional Density? Isn’t it important?
Sectional density is a mathematical expression of an object’s mass in relation to its cross sectional area. For those who want to get into the maths, the formula is the weight of the bullet in pounds, divided by the square of its diameter in inches. The problem with this idea is that we measure it in its static form – when it’s dormant, sitting in the magazine not doing anything. Sectional density is only relevant when it’s actively doing the job. This is of course impossible to measure live, and the results can only be assessed afterward.
Unfortunately, especially with jacketed lead bullets, there is no correlation between the static and dynamic sectional density results. For example, depending on how the bullet was made, it is quite possible for a 220 grain 30 calibre bullet to totally fragment into tiny pieces unless it started out as a solid. This leaves us with only one conclusion: static sectional density is an all but a meaningless expression, and alone doesn’t tell us anything about how a bullet will perform. How the bullet was made can tell us a great deal more.
What are the required energy expectations for a humane harvest?
This is yet another of those armchair expert conversions people have, when sitting around the campfire half tanked and trying to sound wise …
The current paradigm is that a minimum of 1,000 ft/lb of energy is required to humanely harvest a medium game animal, with the scale going up with the size of the animal. This of course sounds reasonable and scientifically sound, but the energy figure on its own, may be meaningless in the context of a ‘Texas heart shot’ buffalo, if the bullet did not maintain its integrity and momentum. One great truism of old is that ‘where you hit it, is more important than what you hit it with’. A modern take on this might be ‘the way the energy is delivered, is more important than how much’. If the vitals were reached and destroyed, the numbers are irrelevant.
Copper bullets and terminal hunting performanceSo why do manufacturers keep talking about static or theoretical numbers like bullet weight, energy, and sectional density, rather than displacement and destructive penetration depth?
In a more generous and conciliatory context, it is a way of benchmarking performance expectations of once similarly made bullets, but without the qualifiers of expansion, momentum and retained bullet structure, these theoretical static descriptors really are quite limited in forecasting terminal performance.
Quite simply, static weight and sectional density are easy to measure in the factory. It is much harder to forecast in a dynamic situation, especially with the huge variations in the terminal performance of jacketed lead bullets, and resistance variations of intended targets.
It’s important to note that jacketed lead bullets have been around for almost 150 years, and in the early days when all bullets were made the same way it might have had some comparative relevance, so in one sense we are stuck in the traditional world and way of thinking. It is simply easier for marketers to write snappy catch phrases, sidestepping difficult subjects altogether, especially ones that may not represent their particular product in the best light.
What are Sintered Bullets? Why don’t we hear anything about them here?
Sintered bullets are predominantly made one of two ways. A metal powder, again, usually copper, is heavily compressed into a die, or a traditional guilding metal cup and then a die, and then heated to bond the otherwise loose external particles together.
Essentially, these bullets are very light as there is air space between the particles, making them highly frangible. These bullets have a very low specific gravity and are used primarily for military and law enforcement training at short range in confined spaces like buildings and aircraft. These bullets are least likely to have any ricochet effect, which is of course essential for officer and third party safety.
Cupped sintered bullets are occasionally used in small calibre cartridges by hunters for varminting purposes, but again, they are limited in range compared to more mainstream alternatives and thus have not proved to be very popular with hunters, except where legislative requirements demand.