Troy Buis Zero Issue

[Whisker]

Good Day!


I'm having an issue sighting in my Troy BUIS.
It seems as if my rifle shoots higher with my Troy than with my carry handle.

I was able to zero at 50m with the small aperture, however, once I switch to the large aperture it seems as if I consistently hit inches (5?) higher. This is ontop of the fact that I had to raise the front sight post to sight in my Troy small aperture, which strikes me as odd as I already sighted in with the carry handle and thought that the elevation should be spot on. I am reluctant to move the front sight post higher as Id like it protected by the wings.

I previously zeroed my carry handle using the large aperture and thus was wondering what changed?

I know a lot of it (all?) can be user error obviously, and if so, what is shooting higher an indication of?

All suggestions welcome!

Oh and happy long weekend! (for those that get it)


Thanks,
Adam

[nickdrak]

The "Issue" with the difference in your point of impact with the small aperture vs. the large aperture is two-fold:

1. Each aperture is typically on a different plane from the other. They make replacement/aftermarket apertures that are "Same Plane". Your Troy rear sight should have a "Same Plane" aperture in it from the factory, unless it is one of the very old Troy's.

2. The large aperture is larger. This will almost certainly cause your point of impact to shift vertically, and your groups will open up a bit than when shooting with the small aperture. This is most likely the cause of your elevation shift between the two apertures.

As far as the fronts sight post goes, what make is your upper? Bushmaster im guessing?

Regardless of the manufacturer, it is highly unlikely that a new flip-up rear iron sight will be "Spot-on" with your previously mounted carry handle sight. Especially if you had elevation dialed into the rear sight elevation drum.

[Whisker]

The "Issue" with the difference in your point of impact with the small aperture vs. the large aperture is two-fold:

1. Each aperture is typically on a different plane from the other. They make replacement/aftermarket apertures that are "Same Plane". Your Troy rear sight should have a "Same Plane" aperture in it from the factory, unless it is one of the very old Troy's.

2. The large aperture is larger. This will almost certainly cause your point of impact to shift vertically, and your groups will open up a bit than when shooting with the small aperture. This is most likely the cause of your elevation shift between the two apertures.

As far as the fronts sight post goes, what make is your upper? Bushmaster im guessing?


FSB is F marked, post is protected when sighted in with the carry handle and small troy aperture.... havent tried to correct for the large aperture elevation change but think that it would not be to good for having the post protected.

Ill be the first to admit that this could very well be me!

but it just seems odd that the carry handle large aperture didnt give me more of a problem..... maybe its a smaller large aperture?

[Whisker]

PS

the Troy BUIS wiggle issue I asked about in another thread...

I doubt it makes any significant difference in my type of shooting...

[nickdrak]

FSB is F marked, post is protected when sighted in with the carry handle and small troy aperture.... havent tried to correct for the large aperture elevation change but think that it would not be to good for having the post protected.

Ill be the first to admit that this could very well be me!

but it just seems odd that the carry handle large aperture didnt give me more of a problem..... maybe its a smaller large aperture?

Zero it with the small aperture only. Dont try to make corrections with the large aperture after zeroing with your small aperture.

What did you have the elevation drum on your carry handle set to when you had it zeroed previously? It should have been bottomed out at 6/3.

[Whisker]

Good point.... I just checked and its set at 6/3, unless someone changed it.

Ill chalk it up to shooter error. Noting also that it seems that I shot more left......

What sort of shooting errors are conducive to shooting high?

Im guessing simple sight alignment?

reverse flinch?

[Whisker]

Came across this googling the issue.

http://shootersforum.com/showthread.htm?t=58774



note post 7

it appears as if he's under the impression that the troy's have an overall higher height above bore than the detachable carry handle?

can anyone who has access to calipers confirm this?

interesting.....