Range Report Flatline 6mm Bullet

Cant wait to hear peoples experience with these.

Special occasions only considering the price though.

What is the BC of this bullet?

Codiekfx400 said:

What is the BC of this bullet?

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G1 - 0.512
G7 - 0.258

Josh of PVA reports 3,260 fps from his 6BR with ease.

Interesting, was expecting something with a bit higher BC.

Seems like you don't get a dramatic ballistic advantage for wind drift, but rather just a bit lighter recoil. Even something like a Dasher/DTAC combo at 2850fps has notably better ballistics and more energy on target out between 1000 and 1200 yards, and the recoil is only about 10% more than a 6BR/Flatline combo up at the PRS speed limit.

Thinking out loud about where I would potentially use these would be on the long range prone stages to get a wind drift advantage, then I'd run cheaper bullets on all the positional stages inside 700 yards. If it's a prone stage then the recoil is not really a factor and I'd just want every last bit of BC I could get.

It would start to become more compelling if it were a 105 bullet with a G7 BC up above .305 or .310, that could run in a 7.5 twist barrel, that could still hit 3050 or 3100fps from a 6BR variant. Then you'd have a gun that could compete with the big 6mm's, but wouldn't have to run a higher recoil barrel burner for the whole match. Not sure if the physics are even possible on that kind of bullet.

Sorry, not getting it?

Assuming PRS or NRL, you can't exceed 3,200 fps, so you really can't take full advantage of this lighter bullet which will run real fast.

Per the posts above, I am at a loss why such a light bullet?

Something in the 105-110 range would make a lot more sense.

I think this bullet was somewhat designed for precision and recoil management, not necessarily to maximize BC. There is a shooter competing on the world scene in the 300m venue using these bullets (see PVA's Facebook pages from a few months ago for more on this shooter).

As I see it, the value prop is: easy to run at >3200fps from the smaller cartridges (= great barrel life/consistent performance thru many rounds), low recoil, easy to get one hole groups at 300m, OK wind drift. You could also make them into a very mean and flat varmint round... send them at 3500 at those damn ground hogs for example.

I would not be surprised if there are more Flatlines in the works for different missions.

Sheldon N said:

It would start to become more compelling if it were a 105 bullet with a G7 BC up above .305 or .310, that could run in a 7.5 twist barrel, that could still hit 3050 or 3100fps from a 6BR variant. Then you'd have a gun that could compete with the big 6mm's, but wouldn't have to run a higher recoil barrel burner for the whole match. Not sure if the physics are even possible on that kind of bullet.

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More of a 100gr bullet for a 7tw with a BC closer to 0.33 is the goal actually. There's very little point in a 7.5tw bullet, the gains just aren't worth the development cost.

The reason this is 88gr is to keep it in an 8tw barrel because that's far more common across all shooting disciplines than the 7tw or 7.5tw that are more popular in field matches.

The recoil difference you're calculating may not sound like it's big on paper, 10%, but keep in mind the difference that it feels from a 6Dasher with 115s vs 105's or a Dasher compared to a 6x47. The Dasher and 47 are only about 10% apart in recoil, a little less than that when I was shooting x47 and moved to Dasher. People talk all the time about reduced recoil from the "full size" 6mm's to a Dasher, this is another step.

The 88's in a BR match the wind performance of a 105 in a Dasher at 1000 yd at sea level for 8% less recoil.
In positional that's a big change.

It's also 17% ahead in drop which many folks negate the effect of because of known distance but there is actually an effect. I used to agree with the thought that drop isn't important and wind was the only real factor but doing hit % predictions I realized that this was not the case. Some of the hit % calculators out there have no way to account for it either but if we look at what the extra drop does in terms of keeping the bullets on target with a marginal trigger break there is an advantage to be had by the flatter trajectory.

That is when an improvised, unstable position begets wobble on target. In a situation where you have more drop and more ToF the waterline is not as tight. That wobble band on target makes the assured impact zone smaller and when you add more drop to the overall equation it increases the effective size of the uncertainty area and reduces the assured impact zone. Assured impact zone is what we're looking for so decreasing that by increasing the drop and ToF equation is a small effect that flatter trajectory aids.

The 88's were not designed to be the highest BC, baddest 6mm in the world. They were designed to augment the use of the little 6mm BR and its variants in matches that go to 1000yd or slightly beyond. In 300m competition like CISM or World Cup it's a large advantage; the sport there is based on tiny % difference advantage and the wind advantage of 10% less ToF and lower recoil is substantial.

As an example of the difference that a slightly lower BC and higher velocity will give you I shot the 95 TMK in my 6BR for the last 2 seasons as a match rifle. After a year of that we embarked on the path to develop the 88 for 8tw barrels. It's not the last 6mm but it's one that can be used now in the widest selection of barrels. It is a large advantage to have the lower recoil, flat trajectory even if there was 0 wind advantage. The 88's offer a wind advantage out to 1000yd too.

At positional stages where recoil is the biggest advantage the 88's show a ballistic wind advantage over the Dasher/105 combo that is slight but the recoil advantage is substantial still.

LRShooter101 said:

Sorry, not getting it?

Assuming PRS or NRL, you can't exceed 3,200 fps, so you really can't take full advantage of this lighter bullet which will run real fast.

Per the posts above, I am at a loss why such a light bullet?

Something in the 105-110 range would make a lot more sense.

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Copper solids don't come close to the same weight as a swaged lead core bullet does, so the same shape projectile is less stable than the lead version would be. Therefore it has hinderances when trying to keep it within a given twist requirement.

The Flatlines have, with few exceptions, been designed to work with standard barrels with standard throats not with exotic twists or throat geometry.
The 88 is a direct plug and play drop into a 6BR and gives ballistic advantage over the 6 Dasher 105 Combo that is turning into the ubiquitous solution.
Even with a disadvantage in teh wind against a 105 in a 6mm Creedmoore the lack of recoil makes for a substantial advantage in many stages.

PRS has turned from long, prone shots on itty bitty targets to movement and improvised positions and problem solving. The 88 in a 6BR is a step towards the laserbeam with 0 recoil.

The same argument for an 88 Flatline in a 6BR is the reason a bunch of folks are doing 22BR and 22Dasher with 88 ELDm
THe 22BR with a 88 ELDm is lower performance in the wind than this and nowhere near the barrel life benefits of keeping a 6 in a BR case.
I have a 22BR, it's awesome and I'm going to be shooting it more next season but it isn't replacing my 6BR.

Thanks Josh, I can see the potential advantages for other disciplines and the twist constraints you had to work within to run these in current barrels. Will be curious to see what you come up with for the 7 twists with a heavier bullet.

Not sure I follow you on flatter trajectory being interplayed with wobble zone to make a smaller or larger "assured impact" zone when dealing with vertical wobble. Maybe it plays out in theoretical math but is it a real world thing? Are you talking about minute fractions of an inch here? I don't know math enough to solve an equation but my gut says it must be incredibly small. If you don't mind, here's a scenario question... If I have a perfectly accurate 2900 fps gun, a 700 yard 2 MOA target, and I break a shot 0.025 degrees above center (1.5 MOA high) due to wobble, how much deviation from the 1.5 MOA "aim point" is there, given the angle of attack of the bullet path? How much better is it if you go to 3200 fps? With such a small angular deviation for the miss, plus what is still a fairly flat trajectory at 700 yards (about the farthest we see wobbly positional targets), I can't picture this being a real thing to consider.

Of course, there are a lot more incorrect ranges given in match books than we'd like, so flat trajectory is a real benefit in that situation.

IMO it's a tough sell on recoil alone. Weight kits have already brought the recoil down to very low levels, and cost/bullet would be significant if you were going to run them the whole match. It would be multiple thousands of dollars a year for me to switch from a traditional 105.

Other question, what does an impact from a copper solid look like vs a lead core bullet on midrange steel? I'm assuming no lead spatter/vapor cloud, so you're relying on target reactivity. Is energy transfer to the plate as good as a lead bullet? Or do they "bounce off" for lack of a better term?

Thanks for the feedback.

I can get that this design was not really a "NRL / PRS" purpose built bullet.

That being said, I am not getting the "making it work in existing barrels"? IMHO, if anyone is seriously competing, and dropping this kind of money on a bullet, then they are going to buy whatever barrel they need to shoot the optimal bullet. If they need a 7 twist to stabilize a 105 bullet, then that is what they are going to buy and hang off their receiver.

Also per the comments above, if you are shooting in a "NRL / PRS" type match, having that additional bullet weight & size is going to make a difference when it comes to spotting impacts, whether they are hits or misses.

Once again, I can get that this was not intended to be an optimal bullet for everyone, but I sure hope that some key people don't really think that this is somehow going to become the answer for shooters running a 6mm in NRL / PRS.

Sheldon N said:

Thanks Josh, I can see the potential advantages for other disciplines and the twist constraints you had to work within to run these in current barrels. Will be curious to see what you come up with for the 7 twists with a heavier bullet.

Not sure I follow you on flatter trajectory being interplayed with wobble zone to make a smaller or larger "assured impact" zone when dealing with vertical wobble. Maybe it plays out in theoretical math but is it a real world thing? Are you talking about minute fractions of an inch here? I don't know math enough to solve an equation but my gut says it must be incredibly small. If you don't mind, here's a scenario question... If I have a perfectly accurate 2900 fps gun, a 700 yard 2 MOA target, and I break a shot 0.025 degrees above center (1.5 MOA high) due to wobble, how much deviation from the 1.5 MOA "aim point" is there, given the angle of attack of the bullet path? How much better is it if you go to 3200 fps? With such a small angular deviation for the miss, plus what is still a fairly flat trajectory at 700 yards (about the farthest we see wobbly positional targets), I can't picture this being a real thing to consider.

Of course, there are a lot more incorrect ranges given in match books than we'd like, so flat trajectory is a real benefit in that situation.

IMO it's a tough sell on recoil alone. Weight kits have already brought the recoil down to very low levels, and cost/bullet would be significant if you were going to run them the whole match. It would be multiple thousands of dollars a year for me to switch from a traditional 105.

Other question, what does an impact from a copper solid look like vs a lead core bullet on midrange steel? I'm assuming no lead spatter/vapor cloud, so you're relying on target reactivity. Is energy transfer to the plate as good as a lead bullet? Or do they "bounce off" for lack of a better term?

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They carry more energy at the plate but there isn't a cloud of lead, they leave a small copper impact mark. It's not hard to see at ranges where we don't have flashers but there is a definite difference in what the impact mark looks like. For the same reasons that matches are required for flashers past a specific distance already the bullets have an issue with being able to see the impact point of a small copper mark vs. a lead splat that is 3x the size. This comes with a silver lining though as there is a distinct advantage on a target which hasn't been painted all day and had its ass whooped by regular bullets. The copper penny looking splats shine clear as day against all the lead marks.

For the drop advantage you need to know the waterline of the load you're comparing it against but here's the easy way to think about it. The "wobble zone" for lack of a better technical term right now is heavily influenced by the waterline of the load being shot. The waterline is the vertical dispersion in a group at a given distance. A tighter vertical dispersion means that targets are statistically larger when held on center to be an assured hit. This is not a new concept and it's one of the oft quoted reasons to go to a Dasher in online discussions... tight waterlines.

The flatlines tighten those waterlines through a few factors, one of them being the consistency from bullet to bullet and the other big factor in this case is the reduced ToF. The lower ToF is a combination of overall performance which we can think of as MV*BC for a normalizing value.

If a given setup shoots a waterline size of X and the new setup shoots a waterline of 0.82*X you have a larger target in many common shapes (diamonds, circles, triangles) because you can tailor where to aim to maximize target size horizontally while being at less risk of dropping a shot high or low out of the target bounds.

The lower the ToF and hence the lower the overall drop value gives a lower dispersion factor because dispersion is based a 3rd order relationship to ToF. This is also a well known behavior: 100yd groups don't translate to 1000yd groups by simply a 10x multipler. It's more like a 25-45x multiplier in actual practice.

So why is that important?

If you can take a 1000yd target and make it look like only say a 925yd target in terms of the ToF then you have an advantage for the effective target impact area. The waterline normally shot at 925 can now be applied to 1000 and the waterline for 600 now applies to 850 and so on. I know when I'm trying to plan a stage I look at target shape as well, it is an important factor on how to shoot them, how to hedge the wind and any concerns over target range.

Same holds true for the application in a wobbly environment. You don't have to steady out quite as much on every shot, you know you have more error margin to work with. Therefore if you have more error margin you can work through the less than optimal position and less than optimal hold while still having the high confidence of a hit in order to execute the shot. This is a time advantage on a wobbly position in a timed stage like a PRS skills barricade.

There isn't enough information in your requested example to give you an idea but the comments should at least explain it to you for the concept.

LRShooter101 said:

Thanks for the feedback.

I can get that this design was not really a "NRL / PRS" purpose built bullet.

That being said, I am not getting the "making it work in existing barrels"? IMHO, if anyone is seriously competing, and dropping this kind of money on a bullet, then they are going to buy whatever barrel they need to shoot the optimal bullet. If they need a 7 twist to stabilize a 105 bullet, then that is what they are going to buy and hang off their receiver.

Also per the comments above, if you are shooting in a "NRL / PRS" type match, having that additional bullet weight & size is going to make a difference when it comes to spotting impacts, whether they are hits or misses.

Once again, I can get that this was not intended to be an optimal bullet for everyone, but I sure hope that some key people don't really think that this is somehow going to become the answer for shooters running a 6mm in NRL / PRS.

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You would be surprised at the people who won't try something if it means a new barrel, I get the call with it every week. There are a few examples but the most outstanding one is consistently the F-T/R with a 308. The trend for 10 years has been heavier heavier heavier. Get every ounce of BC you can, who cares what the recoil or speed is. Enter the 198 Flatline with a verified BC of almost 0.84 G1 out of 308's but it requires a 9twist or faster.

The phone call:
"The 198's look amazing, are those BC's Warner published real?"
Yes, they're tested via Doppler radar now.

"How about throat? Do I need a different throat"
You can use a standard throat, no problem. (Enter hedging bets so other bullets can be used)

"I really want to shoot the 198's in F class but is the 9 twist really necessary"
Absolutely, unless you're over 7500ft DA the 10tw won't work, you really need a 9tw.

"Are you sure? Because <insert bullet manufacturer's name here> recommends a faster twist but it doesn't need it all the time"
I'm quite sure you can't use a 10 twist for this 9 twist bullet. I tried it just to be sure that there wasn't something missing in the math.
"Too bad, maybe next time"

And that's with a 30c bullet that has a massive advantage in both BC (0.84 G1) adn speed (24" 308 runs them over 2800fps) over any other 30c on the market.

Hence why we chose to make a bullet that can be used by the majority of barrels before making something for the competitor willing to drop the money on a new barrel. Shooters are incredibly cheap... I should know, I'm a cheap shooter. If I can't see an advantage it doesn't happen. It is a big factor of why I went from 6x47 to a Dasher (barrel life) and then from a Dasher to a 6BR (barrel life, lower recoil, longer barrel life, easier brass forming, longer barrel life... did I mention longer barrel life?)

bohem said:

There isn't enough information in your requested example to give you an idea but the comments should at least explain it to you for the concept.

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Thanks for the reply, I'm tracking with you now. It's not about angle of departure/angle of attack at the target, you're just essentially saying "Flatlines shoot smaller groups and a tighter waterline". While the math supports tighter waterline due to reduced effect of any given SD/ES due to shorter time of flight and flatter trajectory, my suspicion is that a lot of this will be potentially drowned out by bigger issues like "Does this particular barrel like this particular bullet?" and "Is the load development fully optimized?". The math starts to matter less and downrange results start to matter more for bleeding edge benchrest shooting. Most of the BR guys will tell you that the load with the best ES/SD is not necessarily the one that makes the smallest group at 1000 yards.

That aside, most all 6BR/Dasher/BRA/BRX loads shoot stupid small waterlines already. Any improvement out there is still welcome though.

I keep hearing people say solids just cant shoot the groups that a jacketed bullet can.

How do these compare, what kind of groups at distance have you seen?

Lofty said:

I keep hearing people say solids just cant shoot the groups that a jacketed bullet can.

How do these compare, what kind of groups at distance have you seen?

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My 8.7 twist 308 shoots the 198gr Flatlines tight at 100yds, 0.50" holes. But it wouldn't shoot the 180gr Flatlines for sh*t.

However, where the 198gr really shoots tight is at 20x the distance, 2000yds. Send it, see impact, send another, see impact in exact same spot, etc etc etc. Crazy tight relative to other projectiles. Why? Because the bullet-to-bullet BC variations are lower as are the MV ES/SDs. I'm certain this is due to the better manufacturing tolerances the Warner's can get vs the swaged bullet dies (swaging is basically a boat load of pressure and tolerances are tough to control, whereas Warner's CNCs just buzz along, all day, every day, holding the 0.00001" or whatever they hold). I'm doing zero bullet or brass sorting as well, so its not my loading skills generating these consistent MVs.

I don't have any other experience with any other Flatline in any other cartridge. I do have a 300WSM barrel with a 9 twist on it that needs to get going with the 198gr, but so far, haven't done this.

Add on, as I just thought of it.

My advice: if you have the twist and are interested in one of the Flatlines... buy a box and do some load development in your rifle. See the precision you can get. See the impacts on steel that you get (my 198gr 308 load hits HARD as that bullet is carrying A LOT of energy). Talk to Warners on their recommended powder. 50 rds, ~$70. If they suck after 30 rounds or so, give them to a buddy and see if they work in his barrel. If they do work, you have a major new arrow in your quiver.

What is the oal of the new 6mm flatline w/6mm br combo?

Sheldon N said:

Thanks for the reply, I'm tracking with you now. It's not about angle of departure/angle of attack at the target, you're just essentially saying "Flatlines shoot smaller groups and a tighter waterline". While the math supports tighter waterline due to reduced effect of any given SD/ES due to shorter time of flight and flatter trajectory, my suspicion is that a lot of this will be potentially drowned out by bigger issues like "Does this particular barrel like this particular bullet?" and "Is the load development fully optimized?". The math starts to matter less and downrange results start to matter more for bleeding edge benchrest shooting. Most of the BR guys will tell you that the load with the best ES/SD is not necessarily the one that makes the smallest group at 1000 yards.

That aside, most all 6BR/Dasher/BRA/BRX loads shoot stupid small waterlines already. Any improvement out there is still welcome though.

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The tighter waterlines are half of it. The shooter's wobble zone is affected by the amount of time in the barrel as well. Your stability during the shot break, ignition, bullet transit of the bore is something that compounds as to where the shot leaves the barrel from when your finger set the sequence in motion. It's something we lump together into "follow through" but that starts from the moment your brain says to make the shot fire.

These could be classified as smaller factors but my Dasher shoots 2.5-3"" waterlines at 1000 and 1.5" at 800, since my 6BR can shoot the same waterline at 1000 that the Dasher shoots at 800 then I've made a 10" diamond substantially larger by shooting the 88gr bullet.

Thus far, the bullets have been shot in short and midrange competition. The thing that the olympic shooter noticed shooting these compared to the status quo was that the barrel latency was shorter and the bullet ended up on call or inside of call more often than conventional bullets when shot from the shoulder (his term for out of a sling without support). He attributed this to the lower barrel time from the round going 10% faster at the muzzle. Coming from a guy who's wobble zone at 300m is under 3/4" already that's a pretty impressive notation that he was able to see it and quantify it on his practice targets before taking them to the World Cup.

Edit above: Not sure why but the site doesn't seem to be letting me edit for a correction. His entire group size at 300m is under 3/4" with all effects shot with iron sights, his wobble is smaller than that and the bullets still consistently came in tighter than he was expecting.

bohem said:

Edit above: Not sure why but the site doesn't seem to be letting me edit for a correction. His entire group size at 300m is under 3/4" with all effects shot with iron sights, his wobble is smaller than that and the bullets still consistently came in tighter than he was expecting.

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If you're using your phone, turn it sideways to get the 'Edit' button to show up.

earthquake said:

If you're using your phone, turn it sideways to get the 'Edit' button to show up.

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Good call. I was on my computer that was causing issues but the phone thing has irritated me in the past for sure

Anyone shoot these out of a .243 win?

Dan Warner said:

I think you'll find that they are too new for a lot of direct reports. I don't know of anyone yet that has run them in a 243 Win. But I will say that 3400fps should be a mild load and 3600fps is certainly achievable. Would you like to be the first?

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Yes I would.

Hi,
i'm about to receive my new 6xc and would be very happy to try your 88 grs bullets!
unfortunately i'm in Europe,do you have a dealer here?
i don't want to ask for an import license for a single box to try them!

do you have any report about how your bullets work on game,mostly boar and varmints?

thank you