Terminal performance..... velocity vs energy vs retained weight

[RockyMtnMT]

I have spent a lot of time and resources working on terminal performance. Like many, my quest for better bullets started when I started reloading. I shot bullets that were highly frangible and just could not get over the meat loss, even when the meat was not directly hit. In my quest I found mono bullets. This was the ticket for me as the collateral meat damage is minimal. We shot several diff brands of all copper bullets and had different issues each of them. It was never our intent to become bullet makers, but it just kinda fell in our laps. We wanted to get into the firearms industry and it seemed like a good way in. We soon figured out that there were current patents that we did not want to violate, nor did we want to pay to make bullets. We were able to take our thoughts on what was needed to solve the issue that lead free bullets have and design a bullet that we received a patent on. Our radius drive band design that we call PDR. This allows us to seal the rifle bore without increasing pressure. Turns out it is extremely accurate and forgiving to load for. At this point we thought we were done, now we are bullet makers. All we gotta do is get some copper and turn it down. Not that easy. Terminal performance and accuracy are our top priority. Accuracy was taken care of, but terminal performance we were still chasing. Not all coppers are created equal. And you can't just get a piece of a less common alloy to try. It comes 1k to 2k lbs at a time. We could have used the same copper that other companies do and just been done with it. Again we could not live with the sacrifices in terminal performance at different impact velocities. Lots of impact testing and copper research got us to the alloy that we are currently using. It does what we want regardless of the impact vel. Regardless of the shot placement on bone or no bone. We were after a specific bullet deformation that leaves a flat frontal area on the retained shank that then continues through the animal displacing soft tissue perpendicular to the line of travel. Our bullet is almost fully deformed just under the hide on entrance and makes a large permanent wound channel all the way through the vitals. The old timers in AK used to load bullets backwards for the big bears. That flat frontal area is what gives good deep wounds.



This is what our bullets will do. Middle bullet was a frontal shot that missed the mark and went through the wildebeest right leg, exited, then entered again and recovered by the right hip. The far right bullet was a clean frontal shot recovered in left side hind quarter. The glancing shot on the leg bone did give the typical flat front that the bullet on the right shows. Usually bone hits don't look any different than the bullet on the right.

Creedmoor. If you are in doubt about the stability of your chosen bullet for terminal performance you can test it with some milk jugs. Set them up in a straight line, 6 of them should do, and see if you can catch a bullet. If stability is good the bullet should track straight through the jugs. Poor stability it will veer off line and exit the side of a jug. It is difficult to catch bullets in milk jugs. The more jugs you get through before the bullet turns the better.

I have posted this link before. It is a long read but goes into the physics of how a bullet works. For anybody that is really interested in the subject it is worth the read. http://rathcoombe.net/sci-tech/ballistics/wounding.html

I have a lot of passion for this subject and am more than happy to talk about it. Lets see where this thread goes before I jump too far into the weeds.

Steve

 

[Creedmoor shooter]

I have spent a lot of time and resources working on terminal performance. Like many, my quest for better bullets started when I started reloading. I shot bullets that were highly frangible and just could not get over the meat loss, even when the meat was not directly hit. In my quest I found mono bullets. This was the ticket for me as the collateral meat damage is minimal. We shot several diff brands of all copper bullets and had different issues each of them. It was never our intent to become bullet makers, but it just kinda fell in our laps. We wanted to get into the firearms industry and it seemed like a good way in. We soon figured out that there were current patents that we did not want to violate, nor did we want to pay to make bullets. We were able to take our thoughts on what was needed to solve the issue that lead free bullets have and design a bullet that we received a patent on. Our radius drive band design that we call PDR. This allows us to seal the rifle bore without increasing pressure. Turns out it is extremely accurate and forgiving to load for. At this point we thought we were done, now we are bullet makers. All we gotta do is get some copper and turn it down. Not that easy. Terminal performance and accuracy are our top priority. Accuracy was taken care of, but terminal performance we were still chasing. Not all coppers are created equal. And you can't just get a piece of a less common alloy to try. It comes 1k to 2k lbs at a time. We could have used the same copper that other companies do and just been done with it. Again we could not live with the sacrifices in terminal performance at different impact velocities. Lots of impact testing and copper research got us to the alloy that we are currently using. It does what we want regardless of the impact vel. Regardless of the shot placement on bone or no bone. We were after a specific bullet deformation that leaves a flat frontal area on the retained shank that then continues through the animal displacing soft tissue perpendicular to the line of travel. Our bullet is almost fully deformed just under the hide on entrance and makes a large permanent wound channel all the way through the vitals. The old timers in AK used to load bullets backwards for the big bears. That flat frontal area is what gives good deep wounds.



This is what our bullets will do. Middle bullet was a frontal shot that missed the mark and went through the wildebeest right leg, exited, then entered again and recovered by the right hip. The far right bullet was a clean frontal shot recovered in left side hind quarter. The glancing shot on the leg bone did give the typical flat front that the bullet on the right shows. Usually bone hits don't look any different than the bullet on the right.

Creedmoor. If you are in doubt about the stability of your chosen bullet for terminal performance you can test it with some milk jugs. Set them up in a straight line, 6 of them should do, and see if you can catch a bullet. If stability is good the bullet should track straight through the jugs. Poor stability it will veer off line and exit the side of a jug. It is difficult to catch bullets in milk jugs. The more jugs you get through before the bullet turns the better.

I have posted this link before. It is a long read but goes into the physics of how a bullet works. For anybody that is really interested in the subject it is worth the read. http://rathcoombe.net/sci-tech/ballistics/wounding.html

I have a lot of passion for this subject and am more than happy to talk about it. Lets see where this thread goes before I jump too far into the weeds.

Steve

The 180 eld wasnt my chosen bullet in this particular rifle. I just shot it to get a base line velocity for my new upcoming 7mm build(which will be that rifles #1 bullet). To my suprise it actually shot very well at 100 yards for a starting load. That's when the gears in my head started turning. Then I remembered reading some of your content about proper stability and terminal performance. I'll do as you suggested and try to catch the bullet just to see what it does in a 9.5 twist. It will be interesting to see how it does since I'm driving it just shy of 3000fps

 

[HARPERC]

.....Just to throw something else in here I was schooled by Steve and Rich on twist rate and terminal performance. It seems that a greater stability= better terminal performance...........

Learned a bunch from both these guys, and some of the conversation may be splitting hairs.

At one time we had to choose: Speed whatever that means, vs Heavy whatever that means, stability whatever that means. It's kind of abstract until we start putting in actual numbers. I think there are enough cartridge combo's out there we can have both. At least in the range I'm willing to shoot at game.

Once we do that a certain amount of preference comes into play, based on our experiences in the environments we were most familiar in, and what size game we intend harm to.

SG 1.5 yep can make that work, 1800 fps minimum terminal velocity I can live with that, a bullet that survives in the upper end of whatever muzzle velocity we're working with OK.

If I differ with Steve it's in the balance of velocity, and bullet weight. He will default to velocity, and I will go heavy.

Using his 166 Sledge Hammer, and 84% weight retention yields about 139 grains to carry on when the petals fall away. Something like the Dead Blow 227 grain version retaining about 60% would leave about 136 grains.

It would seem to me, generally the 91 grains of shed petals would yield a bigger wound channel than the 27 grains of the 166. This may be old school, but mass has made a difference in the bigger bones of bigger animals. Having not tested either for penetration I confess this is assumption.

I think the flatter trajectory of lighter bullets will make up for some misjudging of distance, but in these days of laser range finders were not really guessing on the longer shots.

 

[HARPERC]

Deleted duplicate.

 

[Varmint Hunter]

For whatever reason, I am totally hung up on (unnecessary) levels of accuracy in my hunting rifles. I guess it all started out during my many years of shooting LR groundhogs in PA. I have shot out many custom barrels in my endless search for the perfect bullet/load combination.

Based on internet reviews, I decided to try a few Hammer Hunter bullets. I really wasn't expecting anything exceptional in the way of accuracy from a mono bullet but remained open-minded. The first several loads (some from Steve) gave adequate performance but nothing to get excited about. However, I eventually got the 143 HH bullet to shoot well under .5moa at 400yds, reliably. I'm using a Bartlein 8.7 twist in a mid-weight custom hunting rifle rebarreled by Kevin @ Montour County Rifles.

Convinced of the accuracy potential of the Hammer bullets, I ordered some 181 HH bullets for my 30 Nosler which also wears a Bartlein bbl. It wasn't long before I had those bullets shooting well under 2" at 400yds. My club doesn't offer any longer range shooting so that's as far as I've tested the Hammer bullets. To say that I am impressed with the Hammer bullet's accuracy would be an understatement. They shoot like match bullets in my rifles. I hope to Hammer an Elk with the 181 HH this fall. My terminal performance report will follow if I'm lucky enough to connect.

And no - I have no connection to Steve, his partner or anyone else at Hammer bullets. I just call em' like I see em".

 

[Pdvdh]

My only thing with retained weight is I want a pass through. Here in NH its alot of woods and I need a blood trail to follow if they decide to get out of sight, but generally they only go about 35 or so yards and tip over.

My choice depends on the yardage I expect to be shooting the targeted animal. Both monolithic copper and lead core jacketed bullets are accurate enough for any range the bullet remains supersonic. So my choice is based on two additional factors: 1) terminal performance and 2) BC value (= retained velocity) at the yardages I most expect the bullet to strike game.

I dislike meat shredding bullets, so for terminal performance, I prefer the monolithic style bullet and have migrated away from the Bgr and Hrndy style thin jacketed lead core bullets. Depending on shot placement the lead core bullets can explode meat or internal vital organs. The terminal performance depends a combination of impact velocity and location. In the woods of NH and out to 500yds my choice would be simple: monolithic copper bullets.

Hunting at the farthest ranges I expect to shoot game, ~1000yds, the BC value and retained bullet velocity become more important, and begin to take priority. The lead core bullets have the BC value advantage. And at the longest yardages I plan to shoot the bullet velocity has dropped to where meat damage with the lead core bullets is less dramatic and less explosive.

In the past, I've always loaded two different bullets. One for close range and one for long range, due to the above considerations. This year, because monolithic bullets are now available with higher BC values than in years gone by, and due to my distaste for explosive bullets in meat, I've migrated to monolithics for both short and long range hunting. Again, long range meaning 1000yds max.

IF I were focused on hunting yardages beyond ~900yds, I would give preference to the higher BC lead core bullets, with their greater retained velocity and lesser wind drift.

I do still load a second bullet in each cartridge for bear and camp defense, and these are controlled expansion lead core bullets that have passed the test of time for reliable terminal performance at high velocity impacts. Either Swift A-frames or Trophy Bonded Bear Claws. Give me a hand grenade when a bully bear comes looking to eat me.

PS: Edit: And I intended to state my bear defense rounds also work perfectly for game animals out to ~250-300yds.

 

[Korhil78]

I just ordered a box of 100 of the 6.5 124 gr Hammer hunters to test out of my 6.5 Sherman. We shall see how it goes.

When I first got onto this website and started learning about long range hunting and shooting, it was and to some aspect still is to a lot of people all about BC. Most of those people though were shooting out to 2000 yards so it makes since that a high BC bullet would be their choice. And the larger, heavier bullets for caliber made today have the higher BC. To me, and this is just MY opinion, since I shoot 1000 and under, BC doesn't make or break me on a bullet. BC for me is mostly about its wind fighting properties and a heavier bullet helps with that. BUT shooting 1000 and under, if it is really windy, I wont shoot as far as I would at an animal if it were calm. I will try to get closer to where I know my confidence level in making the shot is high. But at 1000 yards, a 15 mph direct cross wind is 7.2 MOA for the 137 gr HH and 8.1 MOA for the 124 gr HH. Its doable with either bullet. The only problem for me is the heavier bullets with the higher BC retain velocity and energy further out. That's why I prefer the heavier bullet.

The affect of the BC of a bullet in conjunction with elevation really means nothing to me because of how easy it is to dial elevation now a days.

Most people like to use a heavier for caliber bullet because when they are shooting longer ranges, a heavier bullet can make up for a flubbed shot better than a smaller bullet can. I have seen this first hand.

I will be able to get these 124 gr hammers to move pretty dang fast out of my Sherman so it will be interesting to see the accuracy and terminal performance. I would prefer to have the 137 gr hammer hunter but my barrel is a 1:8 twist. If I like these bullets, I may get a 1:7 twist just to use them but time will tell.

 

[RockyMtnMT]

I just ordered a box of 100 of the 6.5 124 gr Hammer hunters to test out of my 6.5 Sherman. We shall see how it goes.

When I first got onto this website and started learning about long range hunting and shooting, it was and to some aspect still is to a lot of people all about BC. Most of those people though were shooting out to 2000 yards so it makes since that a high BC bullet would be their choice. And the larger, heavier bullets for caliber made today have the higher BC. To me, and this is just MY opinion, since I shoot 1000 and under, BC doesn't make or break me on a bullet. BC for me is mostly about its wind fighting properties and a heavier bullet helps with that. BUT shooting 1000 and under, if it is really windy, I wont shoot as far as I would at an animal if it were calm. I will try to get closer to where I know my confidence level in making the shot is high. But at 1000 yards, a 15 mph direct cross wind is 7.2 MOA for the 137 gr HH and 8.1 MOA for the 124 gr HH. Its doable with either bullet. The only problem for me is the heavier bullets with the higher BC retain velocity and energy further out. That's why I prefer the heavier bullet.

The affect of the BC of a bullet in conjunction with elevation really means nothing to me because of how easy it is to dial elevation now a days.

Most people like to use a heavier for caliber bullet because when they are shooting longer ranges, a heavier bullet can make up for a flubbed shot better than a smaller bullet can. I have seen this first hand.

I will be able to get these 124 gr hammers to move pretty dang fast out of my Sherman so it will be interesting to see the accuracy and terminal performance. I would prefer to have the 137 gr hammer hunter but my barrel is a 1:8 twist. If I like these bullets, I may get a 1:7 twist just to use them but time will tell.

I very much look forward to your results. I don't get very many folks willing to write about their experience.

Thanks for the order. Working a deadline order to go out on Mon. Should have yours out on Tues.

Steve

 

[Korhil78]

I will also add that it depends on the animal that I am after as well. This 6.5 Sherman will be a dedicated deer rifle if I go with the 124 gr Hammers. I don't want to go that light for elk even though it can be done. But if I like the bullets, I can just get a 7mm or 30 caliber rifle made and use the larger Hammer bullets for those.

 

[WildRose]

Yes I'm bringing this up.... I'm sure this is a dead horse, but I want to discuss this anyway. Alittle back ground on me. I'm a whitetail/black bear hunter as that's all we really have here in NH for medium game. I grew up killing most every deer I shot with a remington corlockt until I got into reloading. I tried nosler partitions which I didnt care for(not enough expansion), hornady sst, and other hunting bullet types. Over the past few years, I gravitated to match bullets, specifically the old a-max and now eld-match. They all killed the deer dead. However, at high velocity(over 3000 fps) I had meat loss and to be honest, didnt seem to kill them any deader than a bullet that held its weight.

So here's what I'm wondering. Does speed kill? Lighter faster bullet? Or does a heavy for caliber and a slower velocity kill better? What about retained weight? 100%? 80%? 50%? none?

I guess I fall in the category of heavy for caliber, and shedding about 50%-75% of its total weight, or whatever needs to remain to give me reliable pass throughs without completely wrecking the meat. I dont do shoulder hits as that tends to ruin alot of meat.

I've been thinking alot about this lately as I need some hunting bullets for my 7mm this year. Just want to hear everyone's thoughts. Let's please keep this as civil as we can fellas.

I'm a freak when it comes to terminal performance. I want controlled expansion and 75% or better weight retention every time no matter what.

I don't want to have to shoot 300gr bullets just so I can hopefully end up with 100-150gr still intact and hopefully passing through.

Choose your shot placement to compliment the bullet choice and put it where it counts and they will die every time.

 

[WildRose]

For whatever reason, I am totally hung up on (unnecessary) levels of accuracy in my hunting rifles. I guess it all started out during my many years of shooting LR groundhogs in PA. I have shot out many custom barrels in my endless search for the perfect bullet/load combination.

Based on internet reviews, I decided to try a few Hammer Hunter bullets. I really wasn't expecting anything exceptional in the way of accuracy from a mono bullet but remained open-minded. The first several loads (some from Steve) gave adequate performance but nothing to get excited about. However, I eventually got the 143 HH bullet to shoot well under .5moa at 400yds, reliably. I'm using a Bartlein 8.7 twist in a mid-weight custom hunting rifle rebarreled by Kevin @ Montour County Rifles.

Convinced of the accuracy potential of the Hammer bullets, I ordered some 181 HH bullets for my 30 Nosler which also wears a Bartlein bbl. It wasn't long before I had those bullets shooting well under 2" at 400yds. My club doesn't offer any longer range shooting so that's as far as I've tested the Hammer bullets. To say that I am impressed with the Hammer bullet's accuracy would be an understatement. They shoot like match bullets in my rifles. I hope to Hammer an Elk with the 181 HH this fall. My terminal performance report will follow if I'm lucky enough to connect.

And no - I have no connection to Steve, his partner or anyone else at Hammer bullets. I just call em' like I see em".

They are essentially "match bullets". Just like my Peregrines each one is machined and milled individually not mass produced on presses.

Are they cheap? Hell no, but you get what you pay for.

 

[WildRose]

Learned a bunch from both these guys, and some of the conversation may be splitting hairs.

At one time we had to choose: Speed whatever that means, vs Heavy whatever that means, stability whatever that means. It's kind of abstract until we start putting in actual numbers. I think there are enough cartridge combo's out there we can have both. At least in the range I'm willing to shoot at game.

Once we do that a certain amount of preference comes into play, based on our experiences in the environments we were most familiar in, and what size game we intend harm to.

SG 1.5 yep can make that work, 1800 fps minimum terminal velocity I can live with that, a bullet that survives in the upper end of whatever muzzle velocity we're working with OK.

If I differ with Steve it's in the balance of velocity, and bullet weight. He will default to velocity, and I will go heavy.

Using his 166 Sledge Hammer, and 84% weight retention yields about 139 grains to carry on when the petals fall away. Something like the Dead Blow 227 grain version retaining about 60% would leave about 136 grains.

It would seem to me, generally the 91 grains of shed petals would yield a bigger wound channel than the 27 grains of the 166. This may be old school, but mass has made a difference in the bigger bones of bigger animals. Having not tested either for penetration I confess this is assumption.

I think the flatter trajectory of lighter bullets will make up for some misjudging of distance, but in these days of laser range finders were not really guessing on the longer shots.

Let me throw you a ringer in here.

It isn't the mass that matters when breaking bone it is the density and how strong the bullet is that gives it it's penetrating capability especially through bone and heavy muscle.

Mass helps, but an easily deforming or breaking up mass will never penetrate tough tissue as well as a stronger, denser bullet that does not separate.

The more frangible the bullet is the more necessary it becomes to have a greater mass to inflict substantial enough damage for a quick kill.

Remember it is the velocity which is squared in the energy equation, not the mass.

 

[HARPERC]

......Let me throw you a ringer in here.
.......It isn't the mass that matters when breaking bone it is the density and how strong the bullet is that gives it it's penetrating capability especially through bone and heavy muscle.
......Mass helps, but an easily deforming or breaking up mass will never penetrate tough tissue as well as a stronger, denser bullet that does not separate.
.........The more frangible the bullet is the more necessary it becomes to have a greater mass to inflict substantial enough damage for a quick kill.
........Remember it is the velocity which is squared in the energy equation, not the mass

Really nothing here I disagree with. It's about how we balance the various factors trying to achieve all things being adequate, if not equal.
I didn't pull it down from another of your post speaking to the quality, and consistency of turned bullets. We're finally at a point where consistent performance, not just lot, to lot, box to box, but from one bullet to the next is available. It's definitely changed my thinking regarding how to manage the variables involved.

 

[uncle_motorhead]

Yes I'm bringing this up.... I'm sure this is a dead horse, but I want to discuss this anyway. Alittle back ground on me. I'm a whitetail/black bear hunter as that's all we really have here in NH for medium game. I grew up killing most every deer I shot with a remington corlockt until I got into reloading. I tried nosler partitions which I didnt care for(not enough expansion), hornady sst, and other hunting bullet types. Over the past few years, I gravitated to match bullets, specifically the old a-max and now eld-match. They all killed the deer dead. However, at high velocity(over 3000 fps) I had meat loss and to be honest, didnt seem to kill them any deader than a bullet that held its weight.

So here's what I'm wondering. Does speed kill? Lighter faster bullet? Or does a heavy for caliber and a slower velocity kill better? What about retained weight? 100%? 80%? 50%? none?

I guess I fall in the category of heavy for caliber, and shedding about 50%-75% of its total weight, or whatever needs to remain to give me reliable pass throughs without completely wrecking the meat. I dont do shoulder hits as that tends to ruin alot of meat.

I've been thinking alot about this lately as I need some hunting bullets for my 7mm this year. Just want to hear everyone's thoughts. Let's please keep this as civil as we can fellas.