Arrow build question?

CJ_BG

FNG
Joined
Sep 21, 2024
Messages
49
In one sentence, shoot the heaviest arrow you can above 260ish FPS if you shoot 27+ inches and/or 60+ lbs, and make sure it tunes well.

It's more nuanced than that though. Speed is accuracy in hunting scenarios, but too much can make broadhead tuning difficult, and you still need to balance momentum. Kinetic energy and FOC are so far down on the priority list I wouldn't even look at them. A 22LR has more KE than most people shoot in their hunting bows. I would try and do your own research to determine what matters to you, but this is how I decide.

I have a 6 step process for determining my arrow builds. If an arrow meets these criteria then I don't worry about the insignificant stuff like gaining an extra half a percent of FOC
  1. What will this arrow be used for
  2. How does this use effect the needs of my arrow
  3. Based on those needs, what do I want from this arrow in regards to velocity and flight characteristics
  4. What grain and diameter arrow will get me those speeds and characteristics
  5. What components will I be using
  6. What arrow will provide these while tuning good in my system.
An example, my prime nexus 4 that I use for almost all my archery hunts

  1. This arrow will be used for hunting varied species of big game in varied terrains with varied broadhead choices
  2. This use means I need a very flexible build in regard to trajectory, wind drift, and broadhead flight, with good weight for penetration. I also want a very robust component system so 4MM arrows are off the table. It will be a 5MM
  3. I want this arrow to shoot between 280 and 290fps for good drop and drift, while still tuning broadheads easily
  4. Everything I have seen, read, and chronographed shows that at 30"/70# (my specs) an arrow between 460 and 500gr will get me those speeds, and it is heavy enough that I have no reservations on penetration
  5. I will be using both regular and lighted nocks, Iron Will vanes, 125gr heads, and would prefer a 50gr insert
  6. Based on the weight of my components, and using my draw weight and length to do a spine determination, I'll need a 250 spine arrow that weighs between 8 and 9.2ish GPI. Victory RIP TKO's fit this nicely with an Iron Will HIIT insert for better strength.
 

big44a4

WKR
Joined
Jul 4, 2017
Messages
643
300, 28” c to c, 28” draw at 70 lbs Mathews V3X 33

Shoot them and find out. I never calculate FOC. Thats a solid arrow setup and you gave yourself tons of room for wrecking arrows and cutting them down to keep using them. Even the victory 50gr stock aluminum TKO half out has been more durable than I expected.

I Robin hooded one arrow last weekend and cut it down to 26” and can still shoot it at 29.5” DL. Will limit broadhead choice since the insert is almost touching the rest but a good pig arrow etc. I also had to change inserts to make it work using a spare one I had left over.
 
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Bump79

WKR
Joined
Oct 5, 2020
Messages
1,296
I apologize if I came across combative - I didn't intend that as I enjoy our discussions and the debate. Please read it in that light.

Trajectory/Range Error:
Please see opening statement from Ashby Foundation Website below. There are Ashby Foundation members and others who have conducted trajectory testing using the same bow with a correct zero at distance to compare actual trajectory drops using a 5 yard plus or minus ranging error. Heavier does drop more however it's not as much as many bowhunters believe.
They say use "the heaviest arrow with a trajectory YOU find acceptable" then some of them are constantly saying that the downsides of trajectory and time in flight aren't factors you should weigh into your setup and it's essentially irrelevant.
This was my next sentence after they aren't' studying it. I shouldn't have been as strong in my statement but I wouldn't describe what Troy does as a study. As a study is only as good as the analysis done after. He did the same thing like what you just said "it's not as much as many bowhunters believe" which is minimizing a huge part of lethality. Hitting in a lethal location.

This is the result of Ranch Fairies testing on range error at 40 yards. I confirmed that the numbers from this test was accurate with Precision Cut Archery. However, there's no way to come to the conclusion that you and he did. He actually did no analysis afterword's and just minimized it. So I'll break it down.
1728125811557.png

Let's use a whitetail as an example. The sizes of the dots are 1.125" to represent a normal cut broadhead. If you were to aim vital V at the green location at 40 yards bringing in a roughly to scale whitetail (standing at 39" tall at the shoulder and 9" high vital). The 434 grain arrow hits 2.3" inches low and the 651 grain hits 3.6 inches low. The 650 grain arrow dropped 57% more than the 434 grain. If the whitetail vital is 9" high and you roughly aim center then you've got 4.5" up or down in forgiveness. Then the added error of 1.3", before any other human error, is 1.3"/4.5"= 30% more error. Over an entire Magnus Black Hornet broadhead high or low.
1728126849670.png
Now as you know, if you're elevated the angle will not give you 9" of clearance to get into vitals so in whitetail elevated situations this is exaggerated. By shooting a heavier arrow, you've increased the odds of hitting bone due to range error. If you're hunting at a feeder or a known stand location this is fine. Not a big deal, but outside of that situation like spot and stalk or mobile styles or hunting this is huge.

If you're shot is high (animal is closer than estimated) it's not as dire as the other direction IF you're shot was perfect anyway. However, if the animal dropped at all I'd still take the 434 grain arrow.
1728127571177.png
Here's another good reference on animal reaction. Lucas prefers heavier arrows - but he acknowledges this downside.

Dr. Ed Ashby alone has taken over 600 live game animals with separate data on each shot to confirm finding on live game. Separate data than culled animal testing.
I may have missed this. So I apologize for that, I'll have to look back into the studies. My point by saying the Ashby Foundation is not studying lethality is that they are studying their theory of lethality. Which is penetration at all costs essentially and denying any physics that contradicts them. Guys like Troy mock or attack if presented data like this. Which is concerning to say the least.

Animal Reaction
Now, let's dive into animal reaction which also is also downplayed in this video by RF. The video is titled "the math doesn't work" and he presented no math, so I will. The question is not will the animal vote to move - it's what happens when it does. As we know they vote to move.

For this example I'll be using Troy's labradar data as he published for a dual cam speed bow at 28.5" and 65#. I'm going to use a distance of 40 yards for this example as well but you're planning for the drop and aim a little lower than I showed above. The arrow weights aren't the exact same as above as he didn't test the same, but you get the idea.

The fixed components are based on studies on Olympic athletes. The issue with film reaction times is that most DSLR cameras used for filming are at like 60-120 frames per second. This somewhat like measuring an engine block with a ruler and saying you're bored over .030". So I'll lean on the human data and we can make our own judgements on if animals react less or more from it.

1728130776734.png

As you can see above - The 616 grain arrow at 40 yards allows 29% more time to move compared to the 436 grain. Given that acceleration means that each second that passes it's moving faster - it can move even more in that added time. The animal if dropping at the acceleration of gravity would drop 50% more than the 436 grain arrow.

This image below isn't accurate as the vital v has closed down with the drop. I also didn't add in the animal moving forward or twisting/rolling. Meaning the 616 is likely a miss completely and the 434 is in the scapula. Theoretically a 360 grain or so arrow might not but you're making a lot of tradeoffs to use that 360 grain arrow (durability, FOC and penetration). What this tells me is that this archer (Troy) is beyond their effective range on that species for this reason. In my opinion nothing outside a crossbow can extend his range to 40 on jumpy critters.
1728129802946.png

Since he's beyond his ethical range on jumpy critters (in my opinion) I wanted to run it at 30 yards which is very common to take these days.
1728131133656.png

Here's the results below. Given that the vital v is closing at this stage with drop - realistically the 616 grain arrow is now in scapula and the 434 grain arrow is below it. So now, without a doubt in my mind the 434 grain arrow, while having less potential for penetration due to mass and a lighter broadhead, completely avoided a bone hit and will most likely still blow through without hesitation. Topped with a quality sharp broadhead I'd argue all day due to this it is a better setup for penetration. Statistically, it's avoiding bone more than the heavier setup. My opinion is that this shows that the 616 grain arrow, for this archer, is beyond it's ethical range of shooting at jumpy critters. At only 30 yards.
1728131457941.png

If we look at equivalencies - the 434 grain arrow if shot at 36 yards would give the animal the same ability to react as the 616 grain arrow at 30 yards. To believe that time in flight isn't relevant is to believe that distance is irrelevant in animal reaction. In fact, some argue that an animal given a further threat distance and lower decibel at further distance will react less. I don't know that to be true so I don't plan for it. I limit my ethical ranges based off this data.

Another equivalency - in order for the slower 651 grain arrow to have the same magnitude of movement as the 434 grain, the archer would need to limit their shots to 25 yards. Which obviously is a good idea to shoot closer. If you want to increase lethality across the board the number one thing you can do is just get closer. However, closer means less opportunities. So the hunter has to balance that out. If you're hunting at a feeder or a food plot you can control shot distance. Which is awesome for that person but I, like others, don't have that ability. So in order to create opportunities.

Chuck Adams has a great writeup about this as well.

Wrapping this up:

I know that normal total arrow weight, moderate FOC and normal sized sharp fixed blades aren't controversial, sexy or click getters. It's not light and mechanical vs heavy and single bevel - there's so much middle ground between those. It's not going to get a single person to donate to a foundation I create in my own name. There's just no free lunch here. Everything listed in the Ashby report has a tradeoff of some sort. Find a balance of them for your application. For Troy with his feeder setup at 17 yards he has a fantastic setup in my opinion. At 17 yards the ability to react is nil, he has zero range error as he put the feeder there, there's no branches in the way because he trimmed them. For what I do, I have no doubt that his setup would be less lethal.

These things are inconvenient truths for the Ashby Fdn. These are just two of them. That's why they don't dig deep into it. For RF, it's just off handed comments that it doesn't really matter. Math shows it does.
 

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Bump79

WKR
Joined
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Messages
1,296
I apologize if I came across combative - I didn't intend that as I enjoy our discussions and the debate. Please read it in that light.

Trajectory/Range Error:


This was my next sentence after they aren't' studying it. I shouldn't have been as strong in my statement but I wouldn't describe what Troy does as a study. As a study is only as good as the analysis done after. He did the same thing like what you just said "it's not as much as many bowhunters believe" which is minimizing a huge part of lethality. Hitting in a lethal location.

This is the result of Ranch Fairies testing on range error at 40 yards. I confirmed that the numbers from this test was accurate with Precision Cut Archery. However, there's no way to come to the conclusion that you and he did. He actually did no analysis afterword's and just minimized it. So I'll break it down.
View attachment 773185

Let's use a whitetail as an example. The sizes of the dots are 1.125" to represent a normal cut broadhead. If you were to aim vital V at the green location at 40 yards bringing in a roughly to scale whitetail (standing at 39" tall at the shoulder and 9" high vital). The 434 grain arrow hits 2.3" inches low and the 651 grain hits 3.6 inches low. The 650 grain arrow dropped 57% more than the 434 grain. If the whitetail vital is 9" high and you roughly aim center then you've got 4.5" up or down in forgiveness. Then the added error of 1.3", before any other human error, is 1.3"/4.5"= 30% more error.
View attachment 773186
Now as you know, if you're elevated the angle will not give you 9" of clearance to get into vitals so in whitetail elevated situations this is exaggerated. By shooting a heavier arrow, you've increased the odds of hitting bone due to range error. If you're hunting at a feeder or a known stand location this is fine. Not a big deal, but outside of that situation like spot and stalk or mobile styles or hunting this is huge.

If you're shot is high (animal is closer than estimated) it's not as dire as the other direction IF you're shot was perfect anyway. However, if the animal dropped at all I'd still take the 434 grain arrow.
View attachment 773187
Here's another good reference on animal reaction. Lucas prefers heavier arrows - but he acknowledges this downside.


I may have missed this. So I apologize for that, I'll have to look back into the studies. My point by saying the Ashby Foundation is not studying lethality is that they are studying their theory of lethality. Which is penetration at all costs essentially and denying any physics that contradicts them. Guys like Troy mock or attack if presented data like this. Which is concerning to say the least.

Animal Reaction
Now, let's dive into animal reaction which also is also downplayed in this video by RF. The video is titled "the math doesn't work" and he presented no math, so I will. The question is not will the animal vote to move - it's what happens when it does. As we know they vote to move.

For this example I'll be using Troy's labradar data as he published for a dual cam speed bow at 28.5" and 65#. I'm going to use a distance of 40 yards for this example as well but you're planning for the drop and aim a little lower than I showed above. The arrow weights aren't the exact same as above as he didn't test the same, but you get the idea.

The fixed components are based on studies on Olympic athletes. The issue with film reaction times is that most DSLR cameras used for filming are at like 60-120 frames per second. This somewhat like measuring an engine block with a ruler and saying you're bored over .030". So I'll lean on the human data and we can make our own judgements on if animals react less or more from it.

View attachment 773190

As you can see above - The 616 grain arrow at 40 yards allows 29% more time to move compared to the 436 grain. Given that acceleration means that each second that passes it's moving faster - it can move even more in that added time. The animal if dropping at the acceleration of gravity would drop 50% more than the 436 grain arrow.

This image below isn't accurate as the vital v has closed down with the drop. I also didn't add in the animal moving forward or twisting/rolling. Meaning the 616 is likely a miss completely and the 434 is in the scapula. Theoretically a 360 grain or so arrow might not but you're making a lot of tradeoffs to use that 360 grain arrow (durability, FOC and penetration). What this tells me is that this archer (Troy) is beyond their effective range on that species for this reason. In my opinion nothing outside a crossbow can extend his range to 40 on jumpy critters.
View attachment 773189

Since he's beyond his ethical range on jumpy critters (in my opinion) I wanted to run it at 30 yards which is very common to take these days.
View attachment 773191

Here's the results below. Given that the vital v is closing at this stage with drop - realistically the 616 grain arrow is now in scapula and the 434 grain arrow is below it. So now, without a doubt in my mind the 434 grain arrow, while having less potential for penetration due to mass and a lighter broadhead, completely avoided a bone hit and will most likely still blow through without hesitation. Topped with a quality sharp broadhead I'd argue all day due to this it is a better setup for penetration. Statistically, it's avoiding bone more than the heavier setup. My opinion is that this shows that the 616 grain arrow, for this archer, is beyond it's ethical range of shooting at jumpy critters. At only 30 yards.
View attachment 773194

If we look at equivalencies - the 434 grain arrow if shot at 36 yards would give the animal the same ability to react as the 616 grain arrow at 30 yards. To believe that time in flight isn't relevant is to believe that distance is irrelevant in animal reaction. In fact, some argue that an animal given a further threat distance and lower decibel at further distance will react less. I don't know that to be true so I don't plan for it. I limit my ethical ranges based off this data.

Another equivalency - in order for the slower 651 grain arrow to have the same magnitude of movement as the 434 grain, the archer would need to limit their shots to 25 yards. Which obviously is a good idea to shoot closer. If you want to increase lethality across the board the number one thing you can do is just get closer. However, closer means less opportunities. So the hunter has to balance that out. If you're hunting at a feeder or a food plot you can control shot distance. Which is awesome for that person but I, like others, don't have that ability. So in order to create opportunities.

Chuck Adams has a great writeup about this as well.

Wrapping this up:

I know that normal total arrow weight, moderate FOC and normal sized sharp fixed blades aren't controversial, sexy or click getters. It's not light and mechanical vs heavy and single bevel - there's so much middle ground between those. It's not going to get a single person to donate to a foundation I create in my own name. There's just no free lunch here. Everything listed in the Ashby report has a tradeoff of some sort. Find a balance of them for your application. For Troy with his feeder setup at 17 yards he has a fantastic setup in my opinion. At 17 yards the ability to react is nil, he has zero range error as he put the feeder there, there's no branches in the way because he trimmed them. For what I do, I have no doubt that his setup would be less lethal.

These things are inconvenient truths for the Ashby Fdn. These are just two of them. That's why they don't dig deep into it. For RF, it's just off handed comments that it doesn't really matter. Math shows it does.
I want to clarify what i meant by beyond effective range in regards to range exclusively. What I should have said was beyond effective range without an exact range. If you have a good range from your rangefinder then range error obviously isn't a limitation. Animal movement still is.
 

ddowning

Lil-Rokslider
Joined
Jul 12, 2023
Messages
287
The real answer is it depends. Above 60# and 28" dl I would not worry about any of it. Penetration is influenced mostly by energy and broadhead sharpness. A hair popping broadhead is a different animal than one that will barely shave hair. It doesn't matter if it is a 2" mech or a magnus stinger. There is a drastic difference in blood on the ground and penetration from a sharp broadhead to a very sharp broadhead.

My daughter got penetration to the vanes on the last deer she shot. 24 yards, 365 grain arrow, 24" dl and 31# dw from a diamond prism. Broadhead was a magnus stinger 100 grain 3 blade sharpened on a kme.

I shoot a 370 grain arrow around 70# dw and 30.5 dl at around 300 fps. Nearly every deer is a complete pass through unless a huge bone is hit. Sometimes they still pass through. That is with a 3 blade 1.75" mech. It doesn't really matter how much dirt you kill after the arrow goes through the animal.

The recent focus on foc and arrow build specs is a waste of time in my opinion. I have had good flight and groups from overspined and under spined arrows as well as foc from 7%-15%.

I would recommend that you shoot for 280 fps with fixed or faster with mechs. Using a properly spined arrow will be a lot more forgiving. If you go after something that needs more penetration, switch to a fixed or coc and adjust weight to slow down if necessary. I have tuned 3 blade fixed to shoot tight groups and same poi as field points up to slightly above 300fps. It was not fun or forgiving though. It is a lot easier at 280 fps.

People seem to stress about arrows a lot. Get a properly spined arrow that has good tight fitting concentric components and you will be in good shape.
 

Beendare

WKR
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May 6, 2014
Messages
9,027
Location
Corripe cervisiam
Ashby has changed his schtick over the years to go more mainstream after his original findings were Laughed out of archery.

His original White paper claimed that EFOC arrows flew further than Avg FOC arrows....along with about 3% better penetration. When the physics guys questioned him....because this defies the laws of physics he admitted the study was done with rubber bands and Soda straws. He has modified that study to remove the stuff that would have Sir Isaac Newton rolling in his grave to now only penetration...when in reality its only the arrow weight that matters.

Here he is on Youtube perpetuating that Hogwash....

Not only that, but he admits he is below avg Trad bow shooter with a very high margin of error in his shooting claiming; very high FOC is a tiny % increase. A guy shooting a longbow with no scientific controls has a high degree of error- more than what the observations claim as an advantage.

Look, that Ashby Foundation is a cash cow...which my bet is some posting here are directly involved.
I would ask them;

Why haven't you shown us the Ashby data sets with the Controlled Scientific study parameters proving VERY high FOC?

Why haven't they done scientifically controlled studies with a Hooter shooter to verify the Anecdotal stuff from Ashby and his longbow? Heck, they have the money.


The answer of course is that the Very high FOC stuff is hogwash. Every pro in every archery discipline and every top bowhunter says so by their actions and would be using very high FOC if it was a thing. Zero do....in fact the guys that know- laugh about it.

It makes sense as tuning is a bell curve with the top of the curve being a sweet spot.
Follow the Easton recommendations and forget the fringe guys padding their retirement.
 

ddowning

Lil-Rokslider
Joined
Jul 12, 2023
Messages
287
Ashby has changed his schtick over the years to go more mainstream after his original findings were Laughed out of archery.

His original White paper claimed that EFOC arrows flew further than Avg FOC arrows....along with about 3% better penetration. When the physics guys questioned him....because this defies the laws of physics he admitted the study was done with rubber bands and Soda straws. He has modified that study to remove the stuff that would have Sir Isaac Newton rolling in his grave to now only penetration...when in reality its only the arrow weight that matters.

Here he is on Youtube perpetuating that Hogwash....

Not only that, but he admits he is below avg Trad bow shooter with a very high margin of error in his shooting claiming; very high FOC is a tiny % increase. A guy shooting a longbow with no scientific controls has a high degree of error- more than what the observations claim as an advantage.

Look, that Ashby Foundation is a cash cow...which my bet is some posting here are directly involved.
I would ask them;

Why haven't you shown us the Ashby data sets with the Controlled Scientific study parameters proving VERY high FOC?

Why haven't they done scientifically controlled studies with a Hooter shooter to verify the Anecdotal stuff from Ashby and his longbow? Heck, they have the money.

The answer of course is that the Very high FOC stuff is hogwash. Every pro in every archery discipline and every top bowhunter says so by their actions and would be using very high FOC if it was a thing. Zero do....in fact the guys that know- laugh about it.

It makes sense as tuning is a bell curve with the top of the curve being a sweet spot.
Follow the Easton recommendations and forget the fringe guys padding their retirement.
I couldn't have said it better myself. I left archery as a 3d shooter (at a high level regionally, but could never put together a winning performance at the national level) at 18 years old. That was 21 years ago. I came back to archery because my kids got interested in bowhunting like dad (I never stopped bowhunting). When I started reading to get caught up with modern coaching and equipment, there was a lot of good stuff. This arrow BS overshadowed all of it. There were so many arguments it was nuts. Nearing 100 big game animals with a bow, and doing most of it with an ibo 3d arrow setup, I knew most of what was being discussed was completely in the weeds and unnecessary. I have no experience with trad bowhunting, but some of it even seems questionable in that context. The easton guidelines are what they are for a reason and they have not really changed much in 30 years.

All this stuff is waisted energy in my opinion. You need fairly straight arrows with a consistent wall thickness and spine. Then you need components that are tight and concentric and nocks that fit the string center serving well. After that it is nice if you have the best spine and following that an FOC between 10% and 15%. If those arrows won't shoot a group you can cover with your fist at 100 yards with field points, it's not the arrows fault.
 

Bump79

WKR
Joined
Oct 5, 2020
Messages
1,296
I couldn't have said it better myself. I left archery as a 3d shooter (at a high level regionally, but could never put together a winning performance at the national level) at 18 years old. That was 21 years ago. I came back to archery because my kids got interested in bowhunting like dad (I never stopped bowhunting). When I started reading to get caught up with modern coaching and equipment, there was a lot of good stuff. This arrow BS overshadowed all of it. There were so many arguments it was nuts. Nearing 100 big game animals with a bow, and doing most of it with an ibo 3d arrow setup, I knew most of what was being discussed was completely in the weeds and unnecessary. I have no experience with trad bowhunting, but some of it even seems questionable in that context. The easton guidelines are what they are for a reason and they have not really changed much in 30 years.

All this stuff is waisted energy in my opinion. You need fairly straight arrows with a consistent wall thickness and spine. Then you need components that are tight and concentric and nocks that fit the string center serving well. After that it is nice if you have the best spine and following that an FOC between 10% and 15%. If those arrows won't shoot a group you can cover with your fist at 100 yards with field points, it's not the arrows fault.
Good points!
 

TheHammer

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Aug 1, 2022
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Location
juneau wi
Some awesome points being made..

My experience and research has me at the conclusion of 286fps is the goal w/12- 15%foc. So I tend to build the arrow with this in mind and tweak the bow to match. Which it seems plenty of hunting setups fall close to this, several of you are consistently harvesting multiple species with no issues.

Good luck to everyone with remaining seasons!
 
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5,392
Location
oregon coast
When building an arrow how do you all typically approach it from a hunting standpoint? I’ve used some different calculators and seen different numbers for speed and kinetic energy depending on arrow weight.

Do you care only about kinetic energy?
Do you try to find a balance of speed and kinetic energy?

Some lower grain builds shoot very fast (and flat) and only sacrifice a little bit of kinetic energy, what do you think about that?

Is there a point of diminishing returns when going up on weight with heavier arrows vs speed?

Just would like to see opinions
Don’t overthink it, you would have to try to build an ineffective arrow build
 

WCB

WKR
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Jun 12, 2019
Messages
3,640
Figure out what diameter I want shoot or how much screwing around I want to do with outserts/inserts etc. Shot micros for a few years...wanted the benefits of less wind rift, "deeper penetration" yadda yadda ...got sick of outsert/insert b.s. and having to upgrade components, went back to larger diamter arrows (GT Hunter Pros) use the stock components...throw on 3 standard Blazer vanes, a broadhead and hunt.

When I really got into bow hunting Blazers were the big vane of the times so that what I had put on my arrows. I've tried others and keep coming back to them.

I guess the point is...stop doing so much thinking and more shooting.

FYI I shoot 68lbs, 383gr arrow set up, @ 27.5". Never had a need for more penetration so far.
 
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