setting up my hha

[scr903]

i dialed in at 20 yards dead on. moved out to 60 set hha on 22 moved to 23 dead on. shot 12 shots on the mark. came back 1 hour later and i did not move anything i had to move dial to 26 to hit the mark it was about 6 inches low. what could cause this inaccuracy. is something causing the bow to loose power or what could it be. thanks for any input. this forum is great info. you dudes have done the homework.

 

[jon.henry755]

Hi scr903,
It could be as simple as a change in the placement of your head or cheek to the eye piece of the scope. It's very important to maintain the exact same distance between your eye and the scope each time you shoulder the crossbow. It usually doesn't cause that much of an adjustment on the HHA, but it can.

One of the best ways to maintain the exact same positioning is to add a check rest to your stock. The stock is an AR15 type stock, so you can go to Cabela's or Brownell if you prefer and do a look up on AR15 Cheek Rests. They are very inexpensive, snap on and do a nice job.

Because the HHA Optimizer Speed Dial adds more height to an already high Weaver Rail Mounting System on the AR15, it's difficult to maintain a good head / Eye alignment on these weapons. A raised cheek piece is the best way I've found. Also, if you're using the UTG / Leapers Scope that comes in the TAC15i Crossbow package, it doesn't help that it has a 4.5 inch eye relief. In my opinion, this puts your head to far away from the scope to maintain good consistency. I much prefer a 3 inch eye relief and a more compact scope.

Regards,

Jon

 

[Len Backus]

Read the thread about scope parallax.

 

[jon.henry755]

Excellent point Len and sorry that I didn't remember the parallax adjustment.

If scr903's parallax adjustment was not correct, it could easily account for this type of problem, so now we have two different possibilities.

He can determine which is the more likely cause based on weather or not he ever touched the parallax adjustment knob anywhere between the first time he created the settings and the second time he went to shoot. If so, it was likely the parallax adjustments, if not it's likely my suggestion.

Regards,

Jon