WTC Flatline bullet testing

BryanLitz

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Guys,

I know this is LRH, but some of you were interested in the performance of the WTC Flatline bullets. So far the 30 cal 180 grain FTR bullet is the only one we've been able to get, and have recently completed some testing with it. Here's my write up with analysis for FTR competition:

We got the Warner Flatline 30 cal 180 grain FTR bullets tested for BC. We shot them from two barrels: 1:8" 308 Win 24" barrel, ave MV ~2300 fps, and a 1:9" 300 Win Mag 26" barrel at 2950 fps. These were both 'nominal' loads, not pushing pressure limits. Normalized results of both barrels for the average speed band 3000-1500 fps.

Results for G7 BC's are: 0.341 and 0.342; nearly identical for the two barrels. Both cases produced SG's over 1.5, so I've got confidence in the results being accurate.

Warner Tool Co advertises G1 and G7 BC's for two different velocity bands: 3000-100 fps and 3500-1500 fps. I'll focus on the 3500-1500 fps band, as taking it to 100 fps can highly skew an average. WTC advertised performance for the 3500-1500 fps band is 0.348. If I calculate the G7 BC for the same band as WTC (3500-1500 fps) based on my testing, it's 0.347.

In essence, when BC is averaged for common velocity bands, my measurements are nearly identical to the WTC advertised performance of this bullet.

Some analysis for FTR.

For the following analysis, we'll consider the G7 BC and form factor (Form Factors: A Useful Analysis Tool | Berger Bullets Blog ) averaged over 3000-1500 fps because that's what all comparable bullets have their BC's figured for, and it's a more likely velocity range for the FTR application.

Here are a few other bullets with their G7 BC's and form factors for comparison (3000-1500 fps averages).
Code:
Bullet							G7 BC	G7 form factor
WTC Flatline 180 gr FTR					0.342	0.793
Berger 200 gr Target Hybrid (unpointed)			0.316	0.954
Berger 200 gr Target Hybrid (pointed*)			0.329	0.917
Berger 215 gr Target Hybrid (unpointed)			0.354	0.915
Berger 215 gr Target Hybrid (pointed)			0.368	0.880

* Assuming nominal +4% BC increase for pointing.

As you can see, the Flatline FTR bullet has about an 8% higher BC than the Berger 200 grain Hybrid, out of the box. Point the Berger 200 grain Hybrid and you close the gap to within 4% of the Flatline bullet. Now consider the 215 grain Hybrid. It's got a higher BC out of the box, and quite higher pointed, but it's also heavier which will affect the MV and ultimately, the wind performance.

Next step of this analysis is to figure the '10-mph crosswind deflection' for each bullet, and see how it plays out on an FTR target at 1000 yards.

Consider the muzzle velocities that are achievable with the different bullets; that will play a part in addition to the BC's.

Solid bullets have some flexibility in their bearing surface/drive band design which often allows for higher velocities at the same pressures compared to conventional bullets which need to engrave the full length of the bearing surface. It's unknown exactly how much extra velocity is possible with the Flatline bullets. For this analysis, we'll assume +50 fps for the solid bullets compared to the conventionals. We'll base everything from a 2650 fps MV for the 200 grain conventional bullet. So we have:

Code:
Bullet						G7 BC	MV	wind deflection in 10-mph crosswind at 1000 yards (inches)
WTC Flatline 180 gr FTR				0.342	2843	59.4
Berger 200 gr Target Hybrid (unpointed)		0.316	2650	74.2
Berger 200 gr Target Hybrid (pointed*)		0.329	2650	70.2
Berger 215 gr Target Hybrid (unpointed)		0.354	2556	67.5
Berger 215 gr Target Hybrid (pointed)		0.368	2556	64.2

Now that we've got the BC's, likely MV's, and calculated wind performance of each bullet, we'll consider the effects on a shooters score in an FTR match, based solely on wind performance.

In the book: Applied Ballistics for Long Range Shooting, I present a series of tables that estimates a likely score for: various classes of shooters (beginner, average, elite), levels of wind performance in terms of inches of wind drift at 1000 yards in a 10-mph crosswind, and what score would result from various levels of wind uncertainty (+/-1mph, +/-2mph, etc). These tables are generated by modeling the various shooter skill levels and simulating the various ballistic performance. The tables track surprisingly well with reality. We'll use them to look up the average scores for elite shooters (averaging 1/2 MOA groups) in easy vs. difficult conditions.
Code:
Bullet						G7 BC	MV	wind	 easy	hard
WTC Flatline 180 gr FTR				0.342	2843	59.5	198-12	189-10
Berger 200 gr Target Hybrid (unpointed)		0.316	2650	74.2	196-5	185-5
Berger 200 gr Target Hybrid (pointed*)		0.329	2650	70.2	196-11	188-8
Berger 215 gr Target Hybrid (unpointed)		0.354	2556	67.5	197-12	187-4
Berger 215 gr Target Hybrid (pointed)		0.368	2556	64.2	197-12	189-0

Reality check; during the recent 2015 FCNC, I was shooting pointed 215 grain Hybrid bullets. From the best to worst conditions, my scores ranged from 198 to 191. This tracks with the predictive model within a point. Not saying it's 100% accurate (being based on statistics, it's just a 'most likely' scenario), but it passes the sanity check.

As you can see, the result of the BC, MV, and wind performance on score is such that the WTC Flatline bullet is definitely a contender among the other options currently being used to win FTR matches.

This analysis focused only on the performance aspect. Precision/grouping/recoil/shoot-ability is another issue which hasn't been fully explored yet. As more of these bullets fly downrange, I'm sure a clear picture will form as to their suitability for FTR competition in general.

-Bryan
 
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Bryan, thanks for putting up your results! But I'm curious, in the first part you talk about the 180gr Flatline, then doing the comparisons with the 200gr. Did you actually mean to say the 200gr is the one you tested? Regardless, that's great news and it seems like WTC claims are pretty close to accurate!
 
Doh!

Thank you for pointing this out, initial post is fixed now.

Apparently I didn't have enough coffee today; I was going back and forth between 180 and 200 on the WTC bullet.

This affected the analysis in the following ways:
* BC is the same at .342, but the G7 form factor is way better for a 180 grain bullet vs. 200.

* Higher MV for the 180 vs. 200

* less wind deflection for the .342 BC bullet at higher MV, and slightly higher score prediction.

Thanks again for pointing out the error.

Grateful for the edit feature!
-Bryan
 
No problem, I knew it seemed a little off that the BC was the same between 20gr different weight bullets! Still very impressive results. Any plan on testing more of Cutting Edge's bullets? I know a lot of people are probably waiting for the results on the .375 cal 400-450gr pills Myself Included. Those 425 and 450 Lazer are wicked :)

Keep up the great work Bryan!!
 
Thank you for your work testing this bullet Bryan. We know youre busy, and yet you still find time to toss out these freebies from time to time. Its very much appreciated.
 
Good morning, Bryan

THank you for posting your testing information.

I noted an oddity about quoting BC's down to 100fps and thought it seemed odd so I went back and checked the WTC website to find a typo that we missed. D'oh!

The 3000-100fps band noted online is actually supposed to be 3000-1500 just liked the 3500-1500fps band. It seems no matter how many times I proof read something there is always something there that I miss until someone else reads it.

I talked to Dan Warner this morning and he said that they will be fixing it ASAP on the website.

ETA: Farmerbrown- Some states may not have restrictions on expanding vs. non-expanding type ammunition for hunting and in those conditions these bullets may be legal from location to location. I am far from an expert on hunting laws across the US but I can say definitively that these bullets would not be legal for hunting of game animals in PA because of the non-expanding type design. As far as the effectiveness on game, I cannot speak to that because we have (due to restrictions I just mentioned) not tried shooting anything living with them to see how they work out.

Officially I would have to say that they are likely not a candidate as a hunting round due to these restrictions. If someone chooses to use them for hunting it is not something that myself or WTC can control, we have to wash our hands of such activity.
 
Bryan: thanks for the review. I'm curious about the extent of copper fouling using these solids. Did you notice any "out of ordinary" copper buildup?

BTW, congrats on your success at Ben Avery (2015 NRA F-Class Nationals) winning the National Championship in both mid-range and long-range categories. What bullets were you using?
 
We only shot enough of them to do the BC test. Haven't shot enough yet to make any observations about fouling. For the Fclass Nationals I was shooting Berger 215 grain hybrids.
 
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