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For those interested in seeing how they spin, this Youtube video is ballistic gel testing of Edgetac 375 grain and 775 grain broadheads. You can see the rotation though ballistic gel. Double bevel (standard) blades have a greater tendency to get stuck in bone, while the rotational force generated by single bevel blades enable them to better penetrate and break though bones like thick ribs or shoulders.

 

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A few more testing observations.

With the BD400 (conventional railed crossbow) , I didn鈥檛 get very good accuracy until I started using arrows with the extreme control of the AV3 vanes.
But, with the X1, the accuracy was even a little better with just the standard 1 degree offset of the very small Heat vanes. The enclosed rail鈥檚 advantages are hard to over emphasize.

A significant finding is that foc has such an effect on BC, which, in turn, has a major effect on trajectory. Traditionally, arrow drop charts show the drops from a horizontal launch (no upward vertical component at all). However, that is not how we sight in. We do have an upward component. The slower the launch, the greater this upward component is. The greater the upward component, the flatter the trajectory will seem.

Comparatively very high foc has a lot of advantages: greater accuracy, crosswind resistance, terminal performance, others(?). A huge, flat single blade broad head is historically very difficult to steer. However, when launched straight out of the SWAT鈥檚 barrel, the 375g large, flat bladed BH flew very accurately with virtually no vane control. FOC has to be the major factor.
In contrast, with the conventionally railed BD400, the broad head needed extreme guidance (AV3s ) to be accurate. Even AV 2s resulted quite inaccurate flight as did helical Blazers (both out of the BD).

Summary.
These broad heads can very accurately be used out of either a conventionally railed or fully enclosed rail crossbow. Accuracy can be excellent, at least through 60 yards. The actual experienced trajectory is much flatter than many of us would imagine (at least me). You鈥檙e not going to bend this broad head!
Don鈥檛 pre-judge the usability of this BH like I did. I will have one X1 set up to hunt with the Edgetac 375 for this next year. This year鈥檚 bear likely won鈥檛 go far!
Huge thank you to SEW for his insightful analysis.

Just want to add a bit more info. Here are the 3 factors we have found to be critical to accurate flight with our large single-bevel broadheads:

1. stiff arrow shafts
The stiffer the better. You have a heavy weight on the front of your arrow (our broadhead), and a string pushing from the opposite end at great force. If the shaft is not stiff enough, it's easy to imagine this will cause the arrow to flex excessively upon launch, resulting in poor accuracy downrange. And that's exactly what happens. You can verify excessive flex (archer's paradox) on slow motion cameras when shooting arrows that aren't stiff enough. (It seems that the X1 is able to mitigate this flexing to a degree with the barrel design of the rail). We're having our best results with double shafted (double sleeved) arrows. Vertical bow shooters are seeing good results with 150 spine arrows. (Note that SEW had excellent results with Black Eagle Zombie Slayer arrows when combined with AV3 vanes)

2. maximum control vanes
We haven't had an opportunity to test AV3's. In own tests, we've had the greatest accuracy with 5.5-inch Magnum Banana feathers (That's right. Real actual bird feathers, not plastic vanes).

3. arrow length
We've seen better results with 22 inch arrows vs 18 and 20 inch.

Bottom line, you need a custom-built arrow to fly these accurately. Total arrow weight (double sleeved with feathers) + 375 grain broadhead is 940 grains.

So these are the tradeoffs: You get the 1.7X increase in momentum, roughly 1.8X the wound channel damage (in gelatin testing), plus the added bone-penetrating/breaking potential of the single-bevel design (this is all vs a 100 grain broadhead), but to achieve these advantages without sacrificing accuracy, you need stiff, heavy, custom arrows with big bird feathers (or as SEW showed, Zombie Slayers with AV3 vanes). Is this overkill? Many would argue it is. That's a question only you can answer for yourself. Obviously it also depends on what you're hunting.
 

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We鈥檙e having a major division of thoughts here.
Sorry SEW, I apologize.

So essentially, I think what SEW is saying is you don't need double-sleeved ultra stiff arrows with big feathers to guide these accurately because you may alternatively get by with AV3 vanes on Zombie Slayer arrows, or you can shoot a more generic Black Eagle Executioner type of arrow IF you are one of the lucky people out there with a Killer Instinct SWAT X1 crossbow which has the enclosed barrel which works to lessen arrow flex, and that's great.

I'm not contradicting his results, just posting our own testing results and I edited ours above to make note of that fact. SEW please let me know if any of this is in error.
 

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In case people out there aren't familiar with some of these terms like
"BD" = Excaliber Bulldog 400 and
X1 = Killer Instinct SWAT X1 crossbow...

SEW, is the following an accurate summary of your data?

SEW's Edgetac 375 grain broadhead test results:

Bow: Excaliber Bulldog 400
Arrow: 20鈥 Black Eagle Zombie Slayer bolts, 110g (Double Tapp?) inserts, flat plastic nocks, AV3 vanes 20鈥 Zombies, Weight total - 691g. 287 FPS, 27.3% FOC
Result: 1" or less group size @ 60 yards

Bow: Killer Instinct SWAT X1 crossbow
Arrow: 22鈥 Killer Instinct shafts (same spine as Black Eagle Executioners - 25% less stiff than Black Eagle Zombie Slayers), non-indexed , 130g inserts, ARC nocks, and 1 degree offset Heat vanes. Weight total 750g. 289 FPS, 26.3% FOC << IMPORTANT NOTE: These arrows will not be stiff enough if shot from a regular crossbow, but they work from a SWAT X1 because of the enclosed barrel design of the bow.
Result: 1/2" groups @ 60 yards
 
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