Greetings from Spain

[AJ01]

https://youtu.be/a2-Bk42-am0

Pretty straight forward information on arrow flight from a crossbow.

[PaulSpain]

ON a hog, the quartering away shot is best followed by the perfect broadside. Straight up the leg, lower 1/3rd of the body will do nicely. I've found that taking out the vessels just above the heart plus bot lungs of course puts things down very fast.

About your shot groups......do the arrows group well with a field point and only get wide with broad heads? If so that points 100% to an arrow problem. With crossbows the stiffer the shaft the better. But they also have to be square. Spin test your broadheads to make sure they spin perfectly true. If not they will spiral down range and cause wide groups. But worse, they do not hit square to the target so you also lose penetration.

There is a lot we could get into but this is a good start to shink your groups.
1) How do the arrows shoot with field points vs broad heads.
2) Test each arrow with each different vane in the rail. You can sometimes dial in a set of arrows to shoot better groups by checking this, and then marking the "good" vane and shooting that arrow like that all the time. This is what I do. Each arrow is numbered, and each vane is a different colore and then the "rail vane" is marked.

Hope this helps

Thanks for the tips!!

I make good groupsets with field and mechanical points, the other day I was testing the order I ordered for four Sevr 2.0 and I made the best groupsets so far (1/2-1 inch), the problem comes when I use the fixed points that I have (toxic-maximal black razor). For both cases I use the same selected arrows in groups of 4 with a maximum difference of 1-2 grain, and I try to compensate the differences with the difference in grains of the tips and the lighted nocks. In the end I am left with total weights with total differences of 1/2 - 1 grain.

I don't know exactly where the problem lies, so I've asked for proflight arrows (the ones that came with the crossbow) and I'll try them and that way I'll clear up my doubts...

I'll keep you posted, so it probably serves as a reference for other newbies.

[PaulSpain]

https://youtu.be/a2-Bk42-am0

Pretty straight forward information on arrow flight from a crossbow.

Good video. Thank you!
It is clear to me that the problem is in the point or in the arrow.
I could order arrows already prepared as it says but I want to learn a little before.

[nchunterkw]

https://youtu.be/a2-Bk42-am0

Pretty straight forward information on arrow flight from a crossbow.

Good video. Thank you!
It is clear to me that the problem is in the point or in the arrow.
I could order arrows already prepared as it says but I want to learn a little before.

Each arrow flexes at the shot and has a spine or "stiff side". You will hear "spine" talked about a lot. It has 2 meanings.

1) It means how much an arrow bends when sitting still in a jig with a weight attached at the middle. Lower spine numbers mean less flex, higher spine means more flex. This is how you choose compound and trad bow arrows as the arrow needs to bend around the riser at launch. So you choose the arrow that will flex properly around your riser given that particular bow setup. Since we are coming out of a rail and don't need to clear a riser...crossbows benefit from very very stiff arrows. But the arrows will still flex a little and it benefits accuracy greatly by matching the spines of all the arrows you shoot. You are doing this a little bit by grouping your arrows.

2) Next is the spine of the arrow in flight. This is called dynamic spine and for our purposes you can think of it has how much the arrow flexes around the center of the arrow in flight. The fletches act to calm down this motion so their relation to the center of the arrow partly determine how well they work.

But the spine is not uniform. The arrows have a stiff side. Its easier to think about an aluminum arrow that is made by rolling a flat piece of aluminum into a tube and welding the seam. The seam will have a bit more metal in it and therefore be stiffer when the arrow launches. If the seam is down on the rail, or up, or right or left....the arrow will fly slightly differently each time. Carbon arrows act similarly. So shooting each arrow 3 times with each different fletch in the rail will help you "spine group" your arrows a bit better.

Finally, since you are shooting an Assassin 400, your arrow is flying very very fast so any little imperfection will cause worse results than in a slower bow. With all that energy, you would benefit greatly from a much heavier arrow, and one that also has a lot of weight in the front (high FOC). If you can find some 300gr broadheads, I think you will like the result.

[PaulSpain]

Each arrow flexes......

How well you have synthesized it for me. Thank you very much.

I'll go for it...

The arrows I was using in theory are spin 400, but I think these Chinese are liars.
I guess that will also have influenced the accuracy.

[PaulSpain]

Well these are my groupings for today at 20 yards with 18" proflight arrows and Sevr Robusto broadheads. I think the problem was the arrows, poor Chinese quality. Black Eagle forever!!
I just need to locate the spines to make robinhoods!!


Could someone tell me if this rubber is only for the sound?
Would it affect durability if I removed it?

[janesy]

No negative effect from removing them.

[PaulSpain]

No negative effect from removing them.

Thanks a lot!!

[nchunterkw]

Well these are my groupings for today at 20 yards with 18" proflight arrows and Sevr Robusto broadheads. I think the problem was the arrows, poor Chinese quality. Black Eagle forever!!
I just need to locate the spines to make robinhoods!!

Now that is the Excal accuracy we are used to seeing.....good shooting.
Are you shooting the 150gr version of the Sevr? With better arrows you can now try fixed heads and should get much better results. I see the Proflights only weigh 250gr. So a 150gr head only puts you at 400gr total weight. I'd go bigger since you are shooting hogs. But you now see the value in a quality arrow shaft. Makes all the difference

[PaulSpain]

Now that is the Excal accuracy we are used to seeing.....good shooting.
Are you shooting the 150gr version of the Sevr? With better arrows you can now try fixed heads and should get much better results. I see the Proflights only weigh 250gr. So a 150gr head only puts you at 400gr total weight. I'd go bigger since you are shooting hogs. But you now see the value in a quality arrow shaft. Makes all the difference

No doubt, lesson learned! Thank you!!

Yes!! The Sevr Robusto, I think there are only 150 gr.

I asked Norm for an estimate those beautiful double-walled arrows, but shipping it is very expensive to Spain.

I'll buy some 20" .003 executioners, cut them down to 18" and insert them to ideal arrow weight.

I'm also buy some 150 gr Slick Trick Xtric.

Here in Europe it is difficult to find boradheads of more than 150 grains, that's why I have to do it based on inserts.
Buying from the USA is very expensive with shipping, so I have to make do with European stocks.

What total arrow weight do you recommend?

[nchunterkw]

For big hogs like you have I'd go around 600 or 700 grains.

Can you get GoldTip arrows there?

The GoldTip Nitro Pro is 13.9 GPI and is the highest I have found. They come 22" long with loose 110gr inserts so you can cut them down.
https://www.goldtip.com/crossbow-bolts/nitro-series/nitro-pro-crossbow-bolts/P01265.html

At 18" that would give you.....13.9*18 = 250.2gr + 110gr insert = 360.2gr.

Add a Lumenok to the back and that gets you 28 grains
https://lumenok.com/collections/all/crossbow-gold-tip-nitro---nitro-pro--272--esi1995341

Buy some German-Kinetics 210gr SilverFlame solid 2 blade broadheads (they are made in Germany) and you are at 598.2gr total weight

GoldTip also has a weight system where you can add more weight to the insert in 10, 20 and 50 grain increments. I would add 50 and you would be right at 650gr.
https://www.goldtip.com/components/fact-weight-system/fact-weight-system/P01333.html

This arrow out of your bow will blow through anything on the planet.

[PaulSpain]

I'll look it up and study it!! Thank you very much!!