Copper Monos - How to choose the right weight(and maybe caliber)?

[Allen Kitts]

Everyone seems to run Mono's lighter for caliber. Follow the guidelines for FPS and FT LBS that each manufacturer publishes and you should be fine. I have killed lots of elk, deer, antelope and bear with Mono's. A lot of them were a 100 grain TTSX out of a 257 Weatherby. Elk to 410 yards with that load and the elk went 15 yards before piling up, deer and antelope out past 500. No extremely long shots by today's standards but the more I do the long range hunting thing the more I learn that a lot can go wrong when you start shooting at animals at longer ranges. I shoot 143 HH in my 280 AI, 169's in my 7 LRM, 181's in my 300 Win Mag and 199's in my 300 PRC. Not just because I am a hammer fan but so far they have been extremely easy to get to shoot really nice groups and they have done their job well on the animals I have taken with them.

Shot placement is extremely critical in my opinion. If you make a bad shot it doesn't matter what grain bullet you are using or how fast it is going you're going to be in trouble 99% of the time.

As to how to determine what weight to hunt with, I still personally go as heavy as I can as long as the twist rate of my barrel can handle the length of the bullet. As long as I can get them to shoot nice tight groups, I'm happy with a little slower but more mass. You can certainly also call Steve (Hammer Bullets) and you can give him the parameters that you have for the hunt, animal's you plan to take and your gun specs and he will give you his thoughts on their mono's and what grain bullet he recommends. I am sure Barnes an other would be happy to do the same. Good luck and let us know what you figure out!

 

[Window]

I have been doing a lot of reading and have a couple of questions I am hopoing that people can chime in on:

Question 1 - How do you choose the right projectile weight? Is a 7mm RM shooting a 100 gr monolithic at 3500fps good for everything (deer, hogs, elk, etc.) or at some point do you need to step up to a heaver projectile?

Question 2 - If you do have to go to a heavier projectile what factors do you use to decide the right weight?

Question 3 - Does caliber matter? Is there going to be an appreciable difference in terminal performance between a 130 gr 6.5mm projectile going 3100 fps vs a .308 caliber 135gr projectile going 3100fps?

Thanks for reading this.

Question 1 - How do you choose the right projectile weight? Is a 7mm RM shooting a 100 gr monolithic at 3500fps good for everything (deer, hogs, elk, etc.) or at some point do you need to step up to a heaver projectile?

Great question and here's my take on it. Light for caliber monos are predictable and reliable as long as you limit them to their minimal impact velocity. For most that'll be around 1800fps. In my opinion, twist rates are crucial and over spinning monos is a good thing especially for straight line penetration. An under spun mono will give unpredictable results. If you are proficient and have the ability/desire to shoot game past that range, traditional bullets will be a better option.

Question 2 - If you do have to go to a heavier projectile what factors do you use to decide the right weight?

Make sure twist rate is substantial.

Question 3 - Does caliber matter? Is there going to be an appreciable difference in terminal performance between a 130 gr 6.5mm projectile going 3100 fps vs a .308 caliber 135gr projectile going 3100fps?

All of the above. To sum it up, it's all about your desire and skill level and there is NOT one bullet that will be the end all be all for every situation. For me, I love to shoot targets at extended ranges and traditional bullets are all I shoot mostly yellow and green box. But for killing deer and elk, it's all Hammers now. I'm a over bore fan and monos fit the bill depending on the need out to 1000 yards and have no desire to shoot a deer or elk beyond that range. Too many variables for me and truth be told I keep it under 800yds because I know when the trigger breaks, there's meat in the freezer.

 

[dougduey]

Velocity is your friend with any mono and you also really need to pay attention to recommended twist rates. I was always a heavy for caliber guy, so I really had to come to terms with shooting lighter mono bullet weights than I wanted.
While I still shoot Bergers, Accubonds, ELDX's, etc, I switched over to using Hammer bullets for hunting about 5 years ago. Like many others that shoot them, I've learned a lot over the last 2 years when hunting with these bullets. I've been nothing but extremely pleased and impressed with the results on game. Biggest takeaway has been "light and fast" is really the mantra. If you want to read some really great info on terminal performance on a very large variety of game, go to the Hammer Bullet forum (Hammer Time) and read the thread called "Hammered Down Under". Lookup posts on here from Fordy, too. It will be enlightening. I remember calling Barnes years ago, and they told me to go down 1 or 2 weight offerings from what I typically used when switching to their bullets. Lighter and faster is what they recommended as well.
Just some food for thought. I shot a great antelope this year at 475 yards with a 120 gr Hammer going 3541 fps. He dropped in his tracks. Same was the case the previous year using a 109 gr Hammer bullet in my 6.5-284 Norma at 3511 fps. The mountain goat in my avatar was taken with a 213 gr Hammer in my 338 Lapua going 3250 fps. I had to put it through his shoulder. It went through both shoulders and liquified his vitals. He did a 180 upon impact and fell over as I was racking another round. I've never had to track any animal shot with a Hammer. Take that for what it's worth. For your 7 Rem Mag, I'd look at the 143 gr Hammer to do all you need, or a 140 gr Barnes if you prefer their bullets
I'm a California native and feel for you. My parents and most of my family are still there. My sis lives in CO and I'm in TX. Great place to grow up, but woke culture and liberal politics has destroyed a gem of a state. I left for grad school in Michigan in '89 and never moved back…..for a reason. A good friend/hunting buddy is a cop in Vallejo. He's counting down his 5 years left until he can retire and move out of there. The same thing is happening to CO.

 

[bigngreen]

You mentioned that there's two factors to SD, diameter and mass. Well, those are two things used to calculate SD, yes, but it's not the only two things that matter regarding terminal performance.

SD is but one part, I may be reading it wrong but you equated monos that retain their weight as maintaining a high sectional density vs a mono that looses weight, the issue is that because a mono that retains it's weight will be at double calibur diameter which which reduces SD far more that blowing off say 40% of weight.

 

[Petey308]

SD is but one part, I may be reading it wrong but you equated monos that retain their weight as maintaining a high sectional density vs a mono that looses weight, the issue is that because a mono that retains it's weight will be at double calibur diameter which which reduces SD far more that blowing off say 40% of weight.

It won't always be at double caliber. That will depend greatly on the design of the mono and it's impact velocity and amount of resistance upon impact.

Also, since SD is directly related to mass, if a bullet loses zero mass it will lose zero SD. If it does lose mass, it will lose SD. I think you're talking about something else. I could be wrong.

 

[Petey308]

SD is but one part, I may be reading it wrong but you equated monos that retain their weight as maintaining a high sectional density vs a mono that looses weight, the issue is that because a mono that retains it's weight will be at double calibur diameter which which reduces SD far more that blowing off say 40% of weight.

Ok so after thinking about it some more, I think I understand what you're trying to say. You're saying that if the bullet expands from .284" to .568 that the SD will effectively be less when you calculate that caliber diameter vs where it started, yes?

I mean, I can follow that logic, but I don't believe that's how it works. I could be wrong. It's not like the whole bullet swells to .568" so it won't calculate out the same.

 

[WYO300RUM]

Many people like to go lighter….much lighter with mono's. I much prefer to use normal cup & core weights to the lower end of normal weights and keep my shots within ranges to assure adequate expansion!

Again my opinion…..use the largest cartridge/caliber that you are comfortable with assuming comparable velocities! There is no substitution for cubic inches! memtb

AKA 426 Hemi

 

[RockyMtnMT]

The greatest factor is choosing a mono bullet for hunting, or any bullet for that matter, is proper stability. I think most stories we hear about bullet failure is due to marginal stability, not the bullet itself. There is a difference between ballistic stability and terminal stability. We list our bullets with a minimum required twist. This is based on terminal stability, not ballistic stability.

I will answer for Hammer Bullets. Our bullets do not require or need more velocity to have good terminal results. Our bullets are all tested down to 1800 fps for full expansion and shedding of the nose. Our bullets are capable of higher vel and we have not been able to impact them too fast. Higher impact velocity will result in more dramatic terminal performance. With that said there is no point, so far, that we have been able to over stabilize, or over spin a Hammer Bullet. Extra twist is a good thing ballistically and terminally.

The single most important thing to choosing a bullet is making sure that you meet the required minimum twist or faster. As long as this is done, the bullet will perform properly.

It was mentioned earlier that over penetration is a problem. This simply is not true. Bullets kill by tearing a hole in the vital tissue to create bleeding. This is a function of the terminal shape of the bullet and the speed that it travels through the vital tissue. As a bullet slows down inside the animal it creates less and less permanent wound until it creates none when it stops. A bullet that properly deforms and maintains higher velocity as it passes through vital tissue continues to create a large permanent wound channel for the entirety of the distance traveled. The goal with Hammer Bullets is to shed the nose in several pieces, typically about 4, and create a flat frontal area on the retained shank. Kind of like if you were shooting a flat based bullet backwards. This flat frontal area will displace soft tissue perpendicular to the direction of the bullet travel. The flat frontal area will displace material greater than a larger rounded mushroom because the rounded mushroom will smoothly part the material with less permanent tearing. The key here is the flat frontal area and being able to get it at high or low velocity impacts. Hammers do this. If I could make a magic bullet, it would change from it's ballistic form on impact to it's terminal form and then pass through the animal without loosing any velocity. This would create the largest possible wound channel. There is no such thing as energy dump. There is such a thing as shock. There is a large shock that is created by Hammers on impact as they open and shed the nose rapidly. This is the same kind of shock that happens with highly frangible lead bullets. The problem with highly frangible lead bullets, is they have a narrow impact velocity that they will work well with. Particularly with high vel impacts. They simply can't take it and will come all apart. Monos that retain all of their weight do need higher velocity to work well. This has created a stereotype that monos need more velocity to work well. This is not true with Hammers.

Then there is the resulting terminal performance from the shed weight. The shed nose petals of Hammers will tend to track with the retained shank and often exit with the retained shank. We often see the main exit hole with a few smaller holes around it. This increases the size of the permanent wound through the animal. If the shed petals radiate outward too much, then they have less contribution to the entire wound channel. Bullets that are scored or broached will shed the petals too easily resulting in less shock on the impact, resulting in less traumatic initial impact and a more outward direction of the petals. Not all copper is created equal. When we found the copper that we use, the terminal results on game were dramatically increased and we were able to get the ideal retained shank form from high or low velocity impacts.

We have made terminal performance our overriding most important factor to making hunting bullets. Nothing is more important than terminal performance in a hunting bullet.

In summery: Minimum required twist or faster for the chosen bullet is most important. Intended hunting distance and game pursued are next. Heavier for caliber bullets will extend the potential range.

Hope this helps and clears up some of the false mono stereotypes that are out there.

 

[memtb]

1. First question has a couple questions in it. Recently I had a new 7mm rifle built. I ordered three sample packs from Hammer: 120, 131 and 143 grainers. I was going to wee which the rifle liked. But I used ignorant prejudice a times. I chose the 131 strictly on looks and didn't use the other two. A 100 mono started at 3,500 fps is good for at least 250 yards on the game you mentioned.

2. I don't have to go to a heavier weight, so I don't have factors to consider.

3. Years ago I posted on Hunt America a question to those who had hunted various small and large animals on at least two continents over at least two decades. I asked if there was any noticeable difference in killing power in what they used. The vast majority said there was no difference in noticeable killing power from about 7mm up to .375. They seemed to agree above .375 there was an obvious difference in killing power. Generally, they based their comments on heart and lung shots. Maybe some here saw that thread.

I remember recently, I'm 78 so recently could be five or ten years ago, a guy was doing culling work on cape buffalo. He and his partner were using full metal jacket round nose bullets. He was using a .30-06 while his partner used a .375H&H. He said in both cases the buffs would run off a ways before they expired.

This is my opinion, and should be be treated as such!

A round nose or pointed non-expanding bullet does little in tissue damage….mostly starts a tear in the tissue, and with tissue being quite elastic moves aside as the bullet passes then closes or mostly so giving a relatively small, permanent wound channel. This could account for the seeming little difference in killing effectiveness.

I think of a comparison of these types (rounded/pointed non expanding) of bullet wounds to that of a puncture wound in your foot from a nail! The actual tissue damage of the wound is rather minimal and the resulting wound hemorrhage is also minimal due to the tissue resuming it's original state.

Things change rather dramatically when the bullet violently expands, causing a much larger temporary wound channel and a larger permanent wound channel. Add to this, the tissue (muscle, vessels, organs) damage done by the tearing/lacerating by the sharp edges of the expanded bullet in combination with the additional tissue damage done by bullet or bone fragments!

If impact velocities are similar, impact points/angles are similar and bullet types are similar….this is where the larger diameter bullet shows improved performance. While numerically the wound channel sizes are not dramatically different…..there's no denying that the greater volume of tissue damage results in greater/faster disruption of life functions! memtb

 

[Franko21]

The greatest factor is choosing a mono bullet for hunting, or any bullet for that matter, is proper stability. I think most stories we hear about bullet failure is due to marginal stability, not the bullet itself. There is a difference between ballistic stability and terminal stability. We list our bullets with a minimum required twist. This is based on terminal stability, not ballistic stability.

I will answer for Hammer Bullets. Our bullets do not require or need more velocity to have good terminal results. Our bullets are all tested down to 1800 fps for full expansion and shedding of the nose. Our bullets are capable of higher vel and we have not been able to impact them too fast. Higher impact velocity will result in more dramatic terminal performance. With that said there is no point, so far, that we have been able to over stabilize, or over spin a Hammer Bullet. Extra twist is a good thing ballistically and terminally.

The single most important thing to choosing a bullet is making sure that you meet the required minimum twist or faster. As long as this is done, the bullet will perform properly.

It was mentioned earlier that over penetration is a problem. This simply is not true. Bullets kill by tearing a hole in the vital tissue to create bleeding. This is a function of the terminal shape of the bullet and the speed that it travels through the vital tissue. As a bullet slows down inside the animal it creates less and less permanent wound until it creates none when it stops. A bullet that properly deforms and maintains higher velocity as it passes through vital tissue continues to create a large permanent wound channel for the entirety of the distance traveled. The goal with Hammer Bullets is to shed the nose in several pieces, typically about 4, and create a flat frontal area on the retained shank. Kind of like if you were shooting a flat based bullet backwards. This flat frontal area will displace soft tissue perpendicular to the direction of the bullet travel. The flat frontal area will displace material greater than a larger rounded mushroom because the rounded mushroom will smoothly part the material with less permanent tearing. The key here is the flat frontal area and being able to get it at high or low velocity impacts. Hammers do this. If I could make a magic bullet, it would change from it's ballistic form on impact to it's terminal form and then pass through the animal without loosing any velocity. This would create the largest possible wound channel. There is no such thing as energy dump. There is such a thing as shock. There is a large shock that is created by Hammers on impact as they open and shed the nose rapidly. This is the same kind of shock that happens with highly frangible lead bullets. The problem with highly frangible lead bullets, is they have a narrow impact velocity that they will work well with. Particularly with high vel impacts. They simply can't take it and will come all apart. Monos that retain all of their weight do need higher velocity to work well. This has created a stereotype that monos need more velocity to work well. This is not true with Hammers.

Then there is the resulting terminal performance from the shed weight. The shed nose petals of Hammers will tend to track with the retained shank and often exit with the retained shank. We often see the main exit hole with a few smaller holes around it. This increases the size of the permanent wound through the animal. If the shed petals radiate outward too much, then they have less contribution to the entire wound channel. Bullets that are scored or broached will shed the petals too easily resulting in less shock on the impact, resulting in less traumatic initial impact and a more outward direction of the petals. Not all copper is created equal. When we found the copper that we use, the terminal results on game were dramatically increased and we were able to get the ideal retained shank form from high or low velocity impacts.

We have made terminal performance our overriding most important factor to making hunting bullets. Nothing is more important than terminal performance in a hunting bullet.

In summery: Minimum required twist or faster for the chosen bullet is most important. Intended hunting distance and game pursued are next. Heavier for caliber bullets will extend the potential range.

Hope this helps and clears up some of the false mono stereotypes that are out there.

Thank you so very much for taking the time to explain. It's great to have access to good information from "the horses mouth" as there is so much bad info floating around out there.

 

[Hard rock]

Thank you so very much for taking the time to explain. It's great to have access to good information from "the horses mouth" as there is so much bad info floating around out there.

You have nothing too loose trying Hammer bullets, they just work .

 

[Calvin45]

I have been doing a lot of reading and have a couple of questions I am hopoing that people can chime in on:

Question 1 - How do you choose the right projectile weight? Is a 7mm RM shooting a 100 gr monolithic at 3500fps good for everything (deer, hogs, elk, etc.) or at some point do you need to step up to a heaver projectile?

Question 2 - If you do have to go to a heavier projectile what factors do you use to decide the right weight?

Question 3 - Does caliber matter? Is there going to be an appreciable difference in terminal performance between a 130 gr 6.5mm projectile going 3100 fps vs a .308 caliber 135gr projectile going 3100fps?

Thanks for reading this.

Light and fast is where it's at with monos. I drive a 120 Barnes tac tx to 4050 fps in my .300 Winnie. @ButterBean does good things with 124 hammers in a .300 Rum. This particular Barnes behaves a lot like a hammer as it's designed for lower velocity of the .300 blk. It sheds its petals and the shank drives deep. Simple Minded Fella on YouTube just uploaded a video of the 120 tac tx in gel from velocity of 1075 to like 3800 or so. At 3200 fps impact (.30-06) velocity the permanent wounding was very broad, blowing the gel block off the table, and the shank penetrated two blocks for 32+ inches of penetration and was stuck in the backstop.

I've killed two deer with it so far at 4050 mv. It's deadly.

In my opinion, heavy high bc monos moving slow are cruel cruel killers.

 

[SWHandldr]

The greatest factor is choosing a mono bullet for hunting, or any bullet for that matter, is proper stability. I think most stories we hear about bullet failure is due to marginal stability, not the bullet itself. There is a difference between ballistic stability and terminal stability. We list our bullets with a minimum required twist. This is based on terminal stability, not ballistic stability.

I will answer for Hammer Bullets. Our bullets do not require or need more velocity to have good terminal results. Our bullets are all tested down to 1800 fps for full expansion and shedding of the nose. Our bullets are capable of higher vel and we have not been able to impact them too fast. Higher impact velocity will result in more dramatic terminal performance. With that said there is no point, so far, that we have been able to over stabilize, or over spin a Hammer Bullet. Extra twist is a good thing ballistically and terminally.

The single most important thing to choosing a bullet is making sure that you meet the required minimum twist or faster. As long as this is done, the bullet will perform properly.

It was mentioned earlier that over penetration is a problem. This simply is not true. Bullets kill by tearing a hole in the vital tissue to create bleeding. This is a function of the terminal shape of the bullet and the speed that it travels through the vital tissue. As a bullet slows down inside the animal it creates less and less permanent wound until it creates none when it stops. A bullet that properly deforms and maintains higher velocity as it passes through vital tissue continues to create a large permanent wound channel for the entirety of the distance traveled. The goal with Hammer Bullets is to shed the nose in several pieces, typically about 4, and create a flat frontal area on the retained shank. Kind of like if you were shooting a flat based bullet backwards. This flat frontal area will displace soft tissue perpendicular to the direction of the bullet travel. The flat frontal area will displace material greater than a larger rounded mushroom because the rounded mushroom will smoothly part the material with less permanent tearing. The key here is the flat frontal area and being able to get it at high or low velocity impacts. Hammers do this. If I could make a magic bullet, it would change from it's ballistic form on impact to it's terminal form and then pass through the animal without loosing any velocity. This would create the largest possible wound channel. There is no such thing as energy dump. There is such a thing as shock. There is a large shock that is created by Hammers on impact as they open and shed the nose rapidly. This is the same kind of shock that happens with highly frangible lead bullets. The problem with highly frangible lead bullets, is they have a narrow impact velocity that they will work well with. Particularly with high vel impacts. They simply can't take it and will come all apart. Monos that retain all of their weight do need higher velocity to work well. This has created a stereotype that monos need more velocity to work well. This is not true with Hammers.

Then there is the resulting terminal performance from the shed weight. The shed nose petals of Hammers will tend to track with the retained shank and often exit with the retained shank. We often see the main exit hole with a few smaller holes around it. This increases the size of the permanent wound through the animal. If the shed petals radiate outward too much, then they have less contribution to the entire wound channel. Bullets that are scored or broached will shed the petals too easily resulting in less shock on the impact, resulting in less traumatic initial impact and a more outward direction of the petals. Not all copper is created equal. When we found the copper that we use, the terminal results on game were dramatically increased and we were able to get the ideal retained shank form from high or low velocity impacts.

We have made terminal performance our overriding most important factor to making hunting bullets. Nothing is more important than terminal performance in a hunting bullet.

In summery: Minimum required twist or faster for the chosen bullet is most important. Intended hunting distance and game pursued are next. Heavier for caliber bullets will extend the potential range.

Hope this helps and clears up some of the false mono stereotypes that are out there.

Steve, this may be the clearest and most concise explanation of your design philosophy I've seen.

Elmer Keith believed in big, heavy bullets at moderate speeds. He knew from experience they create a deep, large diameter wound channel. Seems to me that you've accomplished the same result in a different way, with the additional advantage of working over a wide velocity range (1800 fps >> at least 2X).

Separation of the nose petals, opposed to the textbook 'mushroom' is counter intuitive. Shows that our mental model of how something works often doesn't correspond to reality. You're saying that the individual petals and their wound channels PLUS the blunt-faced rear of the bullet create a 'larger' and more incapacitating wound.

Multiple reports on Hammer bullet performance mention individual exit perforations from the petals around that of the main portion of the bullet. Good evidence that reality often corresponds with your design intent.

I like the idea that your bullets allow us 'eating right up to the hole' without concern about lead ingestion, or loosing an entire quarter to massive damage - while dropping the prey authoritavely.

Your post provides, for me at least, a clear explanation how that happens.

 

[bigngreen]

Ok so after thinking about it some more, I think I understand what you're trying to say. You're saying that if the bullet expands from .284" to .568 that the SD will effectively be less when you calculate that caliber diameter vs where it started, yes?

I mean, I can follow that logic, but I don't believe that's how it works. I could be wrong. It's not like the whole bullet swells to .568" so it won't calculate out the same.

The diameter is the diameter, once it changes SD changed and that bullet has to continue at that diameter UNLESS it sheds diameter, if SD can change with weight loss it will with diameter only it's a greater change.