Hammer ballistic coefficient tests...

[Petey308]

I've said it numerous times- terminal performance of the bullet is the number one priority.

It seems as though the point is continuing to be confused here and some think that I or others are saying that "high BC" is what matters the most. It's not!

The point I'm trying to make is the estimated/published BC is way off from actual. I don't really care what the actual published number is and what the trued number is. What matters is the difference between the two. It could be a high BC bullet or a low BC bullet. It doesn't matter. What matters is that the values advertised vs actual should ideally be pretty close so that the consumer has a good chance on selecting a bullet that will fit their needs and reality closely matches up to expectations.

If you're happy, be happy. How is this not a valid concern of some though? Because a majority don't hunt to distances that it's a factor, it shouldn't even be discussed here? I don't understand the issue there. I think it's a valid concern, regardless of your hunting style, and deserves to be discussed, civilly.

 

[flyguy1]

I just have a simple chronograph, and while I am good at statistics, I'm not sure I understand this thread.

Is the implication that you're shooting at an animal at say, 600 yards without having shot steel or paper (or prairie dogs) at 600 yards many, many times?

You're just plugging in numbers from a 100 yard shot and dialing? That doesn't seem right to me.

 

[QuietTexan]

The point I'm trying to make is the estimated/published BC is way off from actual. I don't really care what the actual published number is and what the trued number is. What matters is the difference between the two.

FWIW even if I don't share it, I do understand your frustration. It would be ideal it there was an industry-wide BC testing standard, and if bullets were labeled with a standardized form factor.

I'd still rather have Steve at the lathe rather than on the range narrowing down his published BC. I also don't think for one hot second he's intentionally inflating numbers to sell Hammers. He has a big enough cult following where we do that for him

 

[Petey308]

FWIW even if I don't share it, I do understand your frustration. It would be ideal it there was an industry-wide BC testing standard, and if bullets were labeled with a standardized form factor.

I'd still rather have Steve at the lathe rather than on the range narrowing down his published BC. I also don't think for one hot second he's intentionally inflating numbers to sell Hammers. He has a big enough cult following where we do that for him

Don't forget about Brian! I'm confident I'll be corrected if I'm wrong, but my understanding is Brian does more with in the shop on the lathes and Steve is more customer relations. I'm sure at times they both do it all though.

If I'm wrong, I'm wrong, and I'll own it. And I mean zero disrespect by that too. I'm not implying customer relations is bad. It's a vital part of the operation. It's a group effort, I know that much.

 

[Northkill]

Discussions like this are good for helping readers understand these factors and how they come to bear (or not) on their particular usage. If more accurate data is the result, the industry benefits. The funny thing is for my rifle it seemed to work out pretty close to the listed BC on the 6.5mm 124 HH. So did the 7mm 150 BD-2 to its listed BC in another rifle of mine. I've only shot to 1k with the BD-2 and to 400 yd with the HH, but that's enough to get a decent idea. I'd like to see more independent testing before we get too far down the road on the bus on this.

 

[Northkill]

I might add that these fast, lighter-for-caliber monolithic designs might lead to a different/custom drag curve model. The little we've played with them seems to indicate that.

G1 BC vs G7 BC vs Bullet-Specific Drag Models

“In the past 4-5 years we’ve made quantum leaps when it comes to predicting bullet trajectories.” –...

precisionrifleblog.com

 

[Petey308]

Discussions like this are good for helping readers understand these factors and how they come to bear (or not) on their particular usage. If more accurate data is the result, the industry benefits. The funny thing is for my rifle it seemed to work out pretty close to the listed BC on the 6.5mm 124 HH. So did the 7mm 150 BD-2 to its listed BC in another rifle of mine. I've only shot to 1k with the BD-2 and to 400 yd with the HH, but that's enough to get a decent idea. I'd like to see more independent testing before we get too far down the road on the bus on this.

I think the terrific speeds mess with the BC's. Running 150 BD-2's from a 7 Allen Mag at around 3,700 fps required changing the G7 (yes, G7) BC to 1.00 out to 400 yds to get it to hold out with real drops. Only shot it to 400 so far with this load, so the rest is just estimated. Crazy stuff. Or what did we do wrong?

Did you figure out the issue with your BC then with that load

Typically, large errors, especially with a really fast MV, can be a result of errors with sight height input and obtaining an accurate zero, particularly if you're trueing BC under 600 yards or so via drops.

Also, for what it's worth, I'd speculate that those versions with less relief grooves, that produce less overall parasitic drag in flight, will result in less difference from estimates BC vs actual.

Obviously differences in Bullet RPM (stability factor) will really affect trued vs estimated too. A mono really needs an SG of at least 2.0 to get the most BC potential. So if you're under that, your actual BC will suffer. The rate of increase in BC over 2.0 though is pretty negligible, but mathematically it will increase.

 

[Hard rock]

I might add that these fast, lighter-for-caliber monolithic designs might lead to a different/custom drag curve model. The little we've played with them seems to indicate that.

G1 BC vs G7 BC vs Bullet-Specific Drag Models

“In the past 4-5 years we’ve made quantum leaps when it comes to predicting bullet trajectories.” –...

precisionrifleblog.com

That's a valid point , that I haven't stated but was in my thoughts , I m sure Steve will chime in on this at some point and explain probably once again how they arrive at their published B.C . I for one have not noticed hardly any wind drift from the 124 gr HH in the 6.5 PRC at 3300 fps at 500 yds with a 15 mph cross wind . Whatever the BC actually is it seems too buck the wind pretty good any thing I would shoot past 200 yds I will verify too establish my own data out too 600 yds . I feel I owe that too the game I'm taking , bullet drop is fairly simple , the wind drift is my main concern. The old saying trust but verify.

 

[Northkill]

Did you figure out the issue with your BC then with that load

Typically, large errors, especially with a really fast MV, can be a result of errors with sight height input and obtaining an accurate zero, particularly if you're trueing BC under 600 yards or so via drops.

Also, for what it's worth, I'd speculate that those versions with less relief grooves, that produce less overall parasitic drag in flight, will result in less difference from estimates BC vs actual.

Obviously differences in Bullet RPM (stability factor) will really affect trued vs estimated too. A mono really needs an SG of at least 2.0 to get the most BC potential. So if you're under that, your actual BC will suffer. The rate of increase in BC over 2.0 though is pretty negligible, but mathematically it will increase.

Good question. That result/observation was from Blaine Painter at Unknown Munitions when he was developing the load. I'm not clear on what he was figuring or seeing, but he was seeing over-achievement out to 400 yds. He's a capable guy, but it's possible he made some data entry mistakes. Since I've had it, I've only shot at 100, 200, and 1,000 to validate further out. At 1k the drops came out real close to the listed BC number. I didn't shoot it at intermediate ranges other than 300 & 400 yds at the two deer I took with it. Those impacts were maybe just a tad high from my POA for dialing based on a G7 .309 drag curve, but hard to quantify or substantiate that from shots taken on moving animals in a hunting environment. I'll be doing more on that as soon as possible for sure.

My experience so far has been that the flight path on these monos are a little different than I've experienced with ELDM's or Bergers. Not necessarily a negative other than it takes a little more work to figure it all out.

 

[Petey308]

Stability on monos, regarding center of pressure vs center of gravity is definitely a different animal than with standard lead core bullets, that's for sure. Flight characteristics can and do change as a result. It's all still calculable though.

 

[Window]

I'll add to this just a little. Saturday morning I went down to our property that was just clear cut and hung a six inch plate from a clearing at 650 yds where I set my shooting table where I'd hoped over the next couple of weeks on a cool morning I'd go shoot a few rounds. My oldest daughter called late yesterday wanting to go shoot pistols whenever I had a chance so I suggested we go today in between rain showers. Long story short, I had four rounds for my 270 Weatherby and five from my 30-378 from last hunting season that needed to be shot to start the upcoming season. Both rifles I'd cleaned to bare metal as soon as season was over last year and have been in the safe since. Dope for both were 11 and 11.2 MOA at 650 and with no fouler rounds, put all nine shot on the plate. These were 117HH's in the 270 and 181 HH's in the 30-378.

This post has for whatever reason has me out shooting my hunting rigs a month before I usually do. I went down today at 11:00 and set an 8" plate at 820 yards after shooting up my leftover hunting rounds a couple of days ago at 650. I loaded six rounds for my 30-378 with 181 Hammer Hunters and shot with my backpack and and a rear bag off my portable shoot table. 16.5 MOA elevation and a 3 o'clock hold for a slight right to left breeze and here are the results.
I'll get some video next time out as before I left today I set a 10" plate at 1100yds. I wouldn't shoot a deer or elk at that range but we'll see what the BC numbers are at the range with the Hammers.

 

[Pdvdh]

This post has for whatever reason has me out shooting my hunting rigs a month before I usually do. I went down today at 11:00 and set an 8" plate at 820 yards after shooting up my leftover hunting rounds a couple of days ago at 650.

Hahaha
Then some good coming from this Thread. Enjoy your range time.

 

[Longrangers]

This post has for whatever reason has me out shooting my hunting rigs a month before I usually do. I went down today at 11:00 and set an 8" plate at 820 yards after shooting up my leftover hunting rounds a couple of days ago at 650. I loaded six rounds for my 30-378 with 181 Hammer Hunters and shot with my backpack and and a rear bag off my portable shoot table. 16.5 MOA elevation and a 3 o'clock hold for a slight right to left breeze and here are the results.
I'll get some video next time out as before I left today I set a 10" plate at 1100yds. I wouldn't shoot a deer or elk at that range but we'll see what the BC numbers are at the range with the Hammers.

I guess I am proud of my 28 nosler with 195 Berger's.

 

[Window]

I guess I am proud of my 28 nosler with 195 Berger's.

I guess I am proud of my 28 nosler with 195 Berger's.

Heck yeah and that's awesome. I'm only running this one at 3220 and not pushing hard. It shoots very well and brass life is exceptional.