hha vertical asjustment

[Luv2turn]

I am trying to zero at 20 yards and have run out of vertical adjustment. I am 2 1/2 inches high and can't lower the scope any more. I called tech support and they told me to lower my rest. I have already paper tuned the bow and explained that lowering the rest would take it out of tune. He told me that is what other tac 15i owners are doing but I haven't seen any postings to support that.

Any other suggestions?

Waiting for a call from HHA to further address my issues.

 

[WildWillie]

I put shims under the scope on the front mount. I was almost 5" high at 20yds

WildWillie

 

[bloodrock]

I lowered the biscuit quite a bit to sight in the scope ( it was hitting over 8" high with no more vertical adjustment left). It was the only option available.
I hope to finish sighting in bow when it returns from limbs being replaced.

 

[jon.henry755]

Hi Luv2turn,
We have heard and seen this problem on more TAC15's lately than you would believe.
The advice that came from WildWillie is the correct solution. Super 91 did 3 crossbows in the past two weeks that all had this same problem. He uses thin walled PVC as his shims and he's stated that it works very well.

I think it was WildWillie that found out that Burris makes a set of rings and a shim set that is made to take care of this problem. There are different sizes available for different scopes. It allows both vertical and horizontal adjustment, so it's perfect for solving this problem.

Russ can you give them the specifics on the rings and shims that you told me about in your lat e-mail?

Jon

 

[hunter1969]

i had to re-machine my scope rings on an angle. Mine was shooting about 10 inches high. I machined them .060" lower at the back, with the rings spaced 4.25 inches apart. lowering the wisker biscuit only made it shoot inconsistent.

 

[Luv2turn]

I put shims under the scope on the front mount. I was almost 5" high at 20yds

WildWillie

What did you use for shims?

 

[WildWillie]

I used a thin piece of aluminum that I cut about 3/8" x 3/4" sandwiched between two pieces of Mole Skin cut to fit as well. I pre-molded the aluminum a bit so it was curved, but when you tighten the scope down it conforms pretty good.

WildWillie

 

[jon.henry755]

Thanks for the shimming tips WildWillie.

I also copied a response from Super 91 on this question and here's the methodology he recommends and uses:

Russ, I have set up three TAC-15's over the past two days, two with the HHA and one without. All three ran out of scope adjustment like you and ended up shooting high. We ended up shimming the scope with thin-wall pvc pipe pieces which are dense and conformed to the inside of the rings perfectly. If you shim the front ring, this will bring you down for your scope adjustment and you can shift it left or right just a little to compensate for the windage.

The main point I wanted to bring out is that PSE has no right providing bad information to their customers. Two wrongs don't make a right and by moving the rest down you are only taking your crossbow further out of alignment. The problem is not in the crossbow or its rest, it's in the Weaver Rail and its ability to align properly with where the scope is pointing.

To simplify the problem I'll explain it like this: When your crossbow is leveled and shooting a perfect center at 20 yards, your scope is aiming some place else (to high and left). The solution is to get your scope pointed at the exact spot where your crossbow is hitting. This is the only way that your crossbow will remain very accurate as you begin to move back and increase your distances. If you do not fix it the correct way, by zeroing the scope to it's center line at 20 yards the problem will continue to worsen as you move further away from the target. Windage is always set at your longest distances because once you have it tuned at 20 yards and deviation will show at the longest yardages. By correcting it at these distances it will be unnoticeable at your short distances.

Hope this helps explain what your trying to achieve.

Jon

 

[Buzzard Bait]

Hi jon.henry755,

The rings you referenced are Burris Signature Zee Rings, 1" or 30mm (Weaver Style or Dovetail). There is also a kit available with inserts of .005" thickness, .010" thickness and .020" thickness for these rings.

There is a review here on LHR in the June articles by M.L. McPherson on these rings. Great explanation of how they work and what they will do!

I have some on order and should get them Tuesday. I'll post my results because I'm trying to solve the same sighting problem as you and Super 91 know.

 

[jon.henry755]

rmbeach,

Perfect answer rm.

Thank you for the input since many of the members can benefit from this advice. Please keep us informed on how this solution works. In my opinion, this is the best solution to the problem and it would be the easiest for most people.

Regards,

Jon

 

[jon.henry755]

Hi All,
I just received the information I've been searching for from one of our members known as rmbeach. We've been working for the last few days on the same set of problems that you guys and many others are experiencing, so rather than elaborate on it, I'm going to post his reply back to me, since I believe it's the best possible solution for all of you.

This is what I would be doing if I had the same problem happening on my crossbow.

Super 91 is great at improvising or creating a custom solution when needed, but sometimes that needs to be reserved for when there isn't already a good off-the- shelf solution readily available. See what you think?

Hi Jon,

The rings you referenced are the Burris Signature Zee Rings, 1" or 30mm (Weaver Style or Dovetail). There is also a kit available with inserts of .005" thickness, .010" thickness and .020" thickness for these rings.

There is a review here on LRH in the June articles by M.L. McPherson on these rings. Great explanation of how they work and what they will do!

I have some on order and should get them Tuesday. I'll post my results because I'm trying to solve the same sighting problem as you and Super 91 know.


Regards,

rmbeach

 

[Luv2turn]

Hi jon.henry755,

The rings you referenced are Burris Signature Zee Rings, 1" or 30mm (Weaver Style or Dovetail). There is also a kit available with inserts of .005" thickness, .010" thickness and .020" thickness for these rings.

There is a review here on LHR in the June articles by M.L. McPherson on these rings. Great explanation of how they work and what they will do!

I have some on order and should get them Tuesday. I'll post my results because I'm trying to solve the same sighting problem as you and Super 91 know.

Where did you order from? I did not think the .020 were avilable for the 30mm ring.

 

[Buzzard Bait]

Luv2Turn, you are correct; the Burris Signature Zee 30mm Rings comes with Burris Concentric inserts and +/- .010" inserts.

I'll send order info in a PM if I can figure out how to send it.

 

[jon.henry755]

Thanks Russ!

I'm sure many of the readers on this forum as well as Crossbow Nation are having this same problem,but don't have the correct solution.

My bet is most have lowered their arrow rests and are living with the results. This is also probably why they've never achieved the type of accuracy that some of us have written about in our articles.

This is just another good example of how problems affecting numerous people can be solved when we work together as a team. Nice job!!!

Regards,


Jon