# Bowtech Sentinel Tuning



## bowpro34 (Jun 17, 2007)

*Sentinel Tuning*

Well bare shaft tuning says to do the same thing... move the rest in towards the riser. The rest is all the way in. I even moved my limb driver behind the riser so that I could get it even closer.

It seems as if the cable roller is pulling so hard on the cables that the cams are pointing towards the riser than than straight ahead...


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## jdcamo (Sep 18, 2006)

My sentinel does the say thing. Left tear. I really dont care about how it shoots through paper. My bh's and fps are hitting together, so that is all that matters to me. It is shooting great. I am getting great groups at 60 and 70 yards.


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## bowpro34 (Jun 17, 2007)

*Sentinel - French Tuning*

Well broadheads are the least of my concerns. I'm aiming for X's right now.

I did French Tune last night (sight in at 9-feet then move back to 60-yards - adjusting arrow rest to find the vertical plane). It worked out well. 

The only thing that bothers me is how crooked the arrows hit up close. That's quite a bit of torque on carbons. I'm fairly certain I would be bending X7's.

I'm understanding now what the pro's mean when they say that tuning through paper is only a starting point. I'm watching the GRIV tuning DVD's yet again and trying to set up this bow perfectly. It takes an unbelievable amount of time though. Hopefully it's worth it in the end.
JS


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## jdcamo (Sep 18, 2006)

I have heard from a couple of other guys that they had the arrow level with the berger holes and that made the difference through paper. Before they had the arrow above the berger holes, but it had a bad left tear. They moved the arrow down, and it shot perfect bullet holes.


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## bowpro34 (Jun 17, 2007)

I actually had my arrow running right below them (you could see the top of the berger holes). That gave me HORRIBLE vane clearance with my blazers. I raise the knocking point and rest. Got the same tear but at least I have vane clearance now.

Whats really scary is that I replaced my blazers with these low profile 2" plasti-fletch shark-fin looking vanes and WOW... The weight is comparable but my arrows are hitting a couple inches higher even at 30-yards. I think there was considerable drag on the blazers for longer distance shooting. Blazers are back n the box until hunting season...

Thanks for your suggestions!
JS


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## ABTABB (Apr 4, 2007)

I had the same problem with My Admiral. Tried every arrow spine, point and rest combination known to Man, and couldn't get it even close to center. I even swapped limbs around and tried spacers, always ended up well inside center. My BT shop (who I trust) told Me most of the Admiral, Captain, and Sentinels He set up were this way but He did have a few tune down the center or slightly outside. I watched a friend set up a Sentinel last night that actually tuned just outside center

My Admiral will shoot a bareshaft like a laser out to 20-30yds, I just don't like 1/3 of My sight being covered up by the riser.


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## bowpro34 (Jun 17, 2007)

I'm with ya there bro... Every Captain, Sentinel I have seen tunes too far inside. I would recommend using the 'Dudley' or French Tuning method. It makes sense too once you think that basically you are just trying to find the vertical plane where the arrow flies 100% of the time. I can deal with 2" sideways tear at 10-feet if it hits the X.

Cliff-notes version of this method...
Sight in as precise as possible at 9 FEET (not yards). Basically try to center the arrow in a specific hole. 

Next go back to 60-YARDS (not feed). Do not move your sight ---- Your vertical height should be close but we are looking for left right.

If at 60-yards your arrow is right, then move your rest out (for RH shooters). Move in if the 60-yard arrow is left. Move your rest very minimally though. 

Go back to 9-feet and set your sights. Then back to 60-yards to check L/R.

It will take a few times so be patient and make sure your shot was perfect before moving anything.
JS


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## jdcamo (Sep 18, 2006)

ttt


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## timbo2 (Apr 22, 2006)

I put .90 thousandths cam spacer bushings on the right side of the cams on the Admiral, Captain, and Sentinel. This moves the center shot from inside of middle to more of a middle spot. You can call Bowtech and get the spacers, then drill them to accomodate the axle bolts. Problem fixed.


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## bowpro34 (Jun 17, 2007)

Ohhhhhhhh - I honestly thought of that but there didn't look like enough room to fit them in there. Awesome - so glad someone actually tried it. I'll be on the horn in a moment!

THANKS


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## jdcamo (Sep 18, 2006)

Is it tough to install the spacers? Do you have to take the cam off?


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## bowpro34 (Jun 17, 2007)

yeah you'll pretty much have to remove the cam. You can slide the axle out without completely removing it.

Might have to remove the strings/cables completely from the bow. Since it is a center pivot bow the press puts the pressure on the ends of the limbs. They rarely line up perfectly enough to easily slide an axle in and out.


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## b_vanfossen (Dec 5, 2008)

nice thing about the center pivot BT's most of them you can loosen the limb bolts enough to remove the string/cables. The captain and one other models doesn't have this feature though. Refer to your manual.

My admiral is going to be here Tuesday. I'm worried about this tuning issue


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## b_vanfossen (Dec 5, 2008)

from what I've researched this is a draw length issue. The Bowtechs are picky about draw length being correct- call me crazy- but measure your arm span and then have someone measure you at full draw. Doesn't hurt anything to do and its free.


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## bowpro34 (Jun 17, 2007)

b_vanfossen said:


> nice thing about the center pivot BT's most of them you can loosen the limb bolts enough to remove the string/cables. The captain and one other models doesn't have this feature though. Refer to your manual.
> 
> My admiral is going to be here Tuesday. I'm worried about this tuning issue


OK you go ahead and have fun with that. I had to turn my peep around so I thought 'No problem, I'll just back out the limb bolts'. Better find something good to watch on tv while you do it. It takes probably 40-50 turns just to get enough slack to remove the peep. I had to put a pencil in place and really had to push to get it back in. Not as easy as you would think. I would recommend you only do that in an emergency situation (like midnight tuning and the bow shop is closed).

I spoke to Bowtech regarding the extra spacer. They strongly advised against it. They didn't say why but didn't like the idea. They suggested trying lots of different arrows and lots of different rests. Tried lots of arrows already. I think I'll just try to make the ones fly that i have now (easton lightspeed 400's). I will take their suggestion of trying a heavier point. Right now 65grain + insert. I tried up to 90, i think I'll try 100's.


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## grigri (Feb 20, 2009)

b_vanfossen said:


> from what I've researched this is a draw length issue. The Bowtechs are picky about draw length being correct- call me crazy- but measure your arm span and then have someone measure you at full draw. Doesn't hurt anything to do and its free.


Hi b_vanfossen:

Would you please elaborate how to judge if the draw length is correct from arm span measurement?

I can overcome the DW very easy with fingers, but after I put my release on, the draw cycle feels a lot tougher near the end, does this mean I have to change the DL?
I'm drawing 28.5", which is my arm span divided by 2.5..

Thanks a lot


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## b_vanfossen (Dec 5, 2008)

bowpro34 said:


> OK you go ahead and have fun with that.


what's your problem? I thought I'd mention it because the only two Bowtechdealers I've asked this to didn't know you could do it. Plus many do not live near a BT dealer.







grigri said:


> Hi b_vanfossen:
> 
> Would you please elaborate how to judge if the draw length is correct from arm span measurement?
> 
> ...


I've been reading a lot on the left tear topic on the BT's. I've pm'd a lot of the people to see what happened in the end result to correct it. The one that sticks out in my mind is the guy had a very tough time drawing because of the draw cycle and he had a bad left tear. It was to the point he was going to get rid of the bow. His bowtech dealer said "lets try this", they shortened his draw from what he always shot and the left tear went away and the draw cycle was easy for him to pull. Now with that said the guy always shot 29" and after they measured him his actual DL was 27"  and put the bow to 26.5" because he uses a d-loop.

To measure app. draw length:

Wingspan measurement divided by 2.5 

or 

Wingspan measurement minus 15 divided by 2. 

To measure bow draw length (distance your actually pulling) vally of the nock to the front of the arrow shelf

or vally of the nock to the belly of the grip + 1.75"

Hope this helps


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## 9 point (Apr 23, 2005)

*I dont know why but it worked*

I shoot at 70#" 30 1/2 in draw and have had Eatson 340's tune great for me out of every bow I have had. They did not out of my Sentinel. I played around and back down to 66 punds and easton 400 st epics and now tear a bullet hole.


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## b_vanfossen (Dec 5, 2008)

awesome! glad you got it

Some peopl tune down to a GT 3555 arrow- I sure hope my GT 5575 (400 spline) is good


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## jdcamo (Sep 18, 2006)

I have also heard that going shorter in draw length helped the left tear.

The admiral, Captain, and Sentinel all are able to be pressed by loosening the limb bolts. Although personally I think pressing them is faster and easier.


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## antler365 (Jan 10, 2009)

jdcamo said:


> I have also heard that going shorter in draw length helped the left tear.
> 
> The admiral, Captain, and Sentinel all are able to be pressed by loosening the limb bolts. Although personally I think pressing them is faster and easier.


Nick Drobak From Bowtech told me to never back out the limbs to work on both my Sentinel or Admiral!!!!! Always press your bow. Not trying to stir things up but this is what he told me.


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## bowpro34 (Jun 17, 2007)

Backing out the limb bolts takes FOREVER anyway. Can't be good for the bow, bolts, or threads.


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## b_vanfossen (Dec 5, 2008)

directly from page 7 of the 2009 Bowtech manual:

"The Center Pivot models (Admiral,
Captain, Sentinel) are “self-pressing”.
Loosening (back-out) the limb bolts
approximately 3” (1” at a time, switching
between the top and bottom limbs)
relaxes the bow so you can remove
and replace the string and cables without
needing a bow press."


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## bowpro34 (Jun 17, 2007)

*Finally got it!!!!*

Just an update....

I had to buy some new arrows to experiment with longer shafts in each range. It appears that this bow loves to shoot weaker arrows. I shot a .400 Lightspeed 3" longer than the rest and with another 25 grains of point weight and BOOM, the Sentinel loves them. Wierd eh? Then I tried a 500 with 100 grain point and same bullethole.

Anything less than a long .400 or heavy point on a 500 and it has a left tear. I guess this is one of those exceptions which proves the rule (left tear doesn't always mean weak arrow).

It was an expensive lesson to learn seeing as how it cost me the purchase of a bunch of different arrows but worth it none-the-less. The extra length will also allow me to take advantage of GRIV's node tuning. Time to get off of here and go do some long range testing. 

I can't guarantee this will work for all of your Captain and Sentinel shooters but it is worth a try. I have seen other posts about it but I guess I just put too much stock into the Easton Arrow Chart which says I should be shooting .340's spine.

Thanks for your help guys. All very appreciated.
JS


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## b_vanfossen (Dec 5, 2008)

JS-

how are you making out with the Easton 500's? Do you have to shoot them at a longer length than u usually do?

i'm having the same problem now

thanks


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## bowpro34 (Jun 17, 2007)

*Lightspeed 500's*

Actually the 500's seem to fly OK as long as I put heavier points in them. I went from the insert + 65 grain point up to insert + 90 grains. They bullet hole perfectly.

I am also experimenting with 400's. I had to actually buy new 400's and leave them about 2.5" longer along with 90 to 100 grain points.

I shot the 500's in a field round on Sunday and they flew very well. I'm going to do the same with the 400's this weekend. I'll have more info then.

In short, it looks like you need to push the spine a little bit harder than normal to get them to fly. At least this is true for my bow.

Let me know if there's anything else you need.
JS


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## Bulldogjohn (Jun 9, 2012)

Hi guys just bought a 2009 Sentinel and same thing it has a 1 inch left paper tear. anyway it is true the Sentinel tunes inside of center. to get it any where near center this bow loves weak spine arrows but I fixed the problem. The 2010 models have a flex guard which fixes the problem so I went to the local archery store and ordered a PSE flex guard and put it on and boom center shot bullet holes. Here's some photos/ just needed to add a peace of plastic and that's it.


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## frank124444 (Apr 28, 2013)

Bulldogjohn said:


> Hi guys just bought a 2009 Sentinel and same thing it has a 1 inch left paper tear. anyway it is true the Sentinel tunes inside of center. to get it any where near center this bow loves weak spine arrows but I fixed the problem. The 2010 models have a flex guard which fixes the problem so I went to the local archery store and ordered a PSE flex guard and put it on and boom center shot bullet holes. Here's some photos/ just needed to add a peace of plastic and that's it.
> View attachment 1983845


Thanks for posing these great results! but i do have a few questions.
for starters does the slides actually slide?
and have any clue where i can buy the pse FleXX guard since i can only find the plastic pieces on the net.


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## BrianD (Sep 28, 2009)

Dredging this back up a bit. I just picked up a sentinel to play with.
I am assuming the '10 flex guard cannot simply be swapped to the '09?
I've gotten the cam rotated to my draw length but how do I know what hole to put the draw stop into?


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## frank124444 (Apr 28, 2013)

BrianD said:


> Dredging this back up a bit. I just picked up a sentinel to play with.
> I am assuming the '10 flex guard cannot simply be swapped to the '09?
> I've gotten the cam rotated to my draw length but how do I know what hole to put the draw stop into?


the 10flex guard doesnt fit the 09 due difference in riser. as for the draw length and mod-post there should be a file on google for that.
http://www.bowtecharchery.com/admin/project/uploads/BT09_modpost.pdf


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