Hold sensitive PCP

no avatar
poguemahone
Posts: 688
Joined: Sun Feb 15, 2015 10:36 am
Location: stoke

Re: Hold sensitive PCP

Sun Mar 15, 2015 12:14 pm

wastrel wrote:Couldn't disagree more with the elevatated POI posts.
POI does/should NOT change with an elevated or downhill shot at UK airgun power levels, ever, factamondo!
I'd be checking for hold sensitivity points on my rifle for a 1.5 inch change at any distance or elevation.
FT/HTF shooters will back me here (help Ray!)

not if they've got any sense they wont :lol: :lol: :lol: :lol: :lol:

User avatar
Raj
Posts: 2005
Joined: Sun Feb 15, 2015 9:36 pm
Location: Rugby

Re: Hold sensitive PCP

Sun Mar 15, 2015 12:38 pm

Interesting post, Wastrel. What is your statement based on, my friend? :) Genuine objective question - not leading you on or anything.
“It's the Indian, not the arrow"

no avatar
wastrel
Posts: 876
Joined: Sun Feb 15, 2015 5:26 pm

Re: Hold sensitive PCP

Sun Mar 15, 2015 12:51 pm

I've never changed my point of aim if aiming up or downhill, the mildots on my scope & holdover are all I adjust for distance, rifles zero'd at 25m!
AA S200
Walther LGU
Westlake fit for the bin
Webley Raider 10
Walther underlever
1st Grand Order member

no avatar
wastrel
Posts: 876
Joined: Sun Feb 15, 2015 5:26 pm

Re: Hold sensitive PCP

Sun Mar 15, 2015 12:55 pm

If I stood on a ridge & put a target 25m in front of me, one up a tree at 25m & one below me at 25m, gun zero'd at that distance I'd hit the bull on each without moving my crosshairs from the bull (on a good day)
Edit:- I actually do this on my permission regularly to zero my rifle! can`t think why anyone would think it`s a big deal? up or down POI doesn`t change, not at those distances anyway, & the reason I mention airguns & uk power limits is, it may change with powderburners at the distance they shoot at, not us though!
reading the OP I wondered if he`d changed pellets, 1.5" shift ---at 30m!! I`d be looking at hold points/sensitivity all day long!
AA S200
Walther LGU
Westlake fit for the bin
Webley Raider 10
Walther underlever
1st Grand Order member

no avatar
Axelrod
Posts: 109
Joined: Sun Feb 15, 2015 3:44 pm
Location: Almeria Spain.

Re: Hold sensitive PCP

Sun Mar 15, 2015 2:07 pm

I would like to agree with wastrel, but i used to have the same problem. At the distance you were shooting an inclined shot could well be out with a head shot. My cure was to fit a scope bubble and allow for angle. dave

no avatar
wastrel
Posts: 876
Joined: Sun Feb 15, 2015 5:26 pm

Re: Hold sensitive PCP

Sun Mar 15, 2015 2:08 pm

re-reading the OP,- James, are you zeroing the gun from a rested position then shooting free hand? that would account for a shift of 1.5"?
can`t believe no-one`s posting about this, maybe you`re all out shooting, 1.5" shift at 30m??
AA S200
Walther LGU
Westlake fit for the bin
Webley Raider 10
Walther underlever
1st Grand Order member

no avatar
poguemahone
Posts: 688
Joined: Sun Feb 15, 2015 10:36 am
Location: stoke

Re: Hold sensitive PCP

Sun Mar 15, 2015 2:51 pm

wastrel wrote:If I stood on a ridge & put a target 25m in front of me, one up a tree at 25m & one below me at 25m, gun zero'd at that distance I'd hit the bull on each without moving my crosshairs from the bull (on a good day)
Edit:- I actually do this on my permission regularly to zero my rifle! can`t think why anyone would think it`s a big deal? up or down POI doesn`t change, not at those distances anyway, & the reason I mention airguns & uk power limits is, it may change with powderburners at the distance they shoot at, not us though!
reading the OP I wondered if he`d changed pellets, 1.5" shift ---at 30m!! I`d be looking at hold points/sensitivity all day long!

aye up Sie, dont know what gun, calibre, or pellets you're using to defy the laws of gravity, but from a 30yd zero, s400 in .177, jsb exacts, i cant defy it, and shooting upwards by 45 degrees requires around 1/2" holdunder @ 30 yds. shooting downwards at the same range and angle would also require this holdunder ;)

User avatar
james79
Posts: 249
Joined: Sun Feb 15, 2015 7:59 pm

Re: Hold sensitive PCP

Sun Mar 15, 2015 2:58 pm

wastrel wrote:re-reading the OP,- James, are you zeroing the gun from a rested position then shooting free hand? that would account for a shift of 1.5"?
can`t believe no-one`s posting about this, maybe you`re all out shooting, 1.5" shift at 30m??


Yup, that's right, zeroed from a rested position and then shooting sat leant against some bales resting off the knee. It's never caused me a problem before and wouldn't have thought with a PCP it would :)
The first principle is that you must not fool yourself and you are the easiest person to fool

User avatar
raygun
Posts: 397
Joined: Sun Feb 15, 2015 3:41 pm

Re: Hold sensitive PCP

Sun Mar 15, 2015 3:50 pm

Parallax error.

You are not looking through the scope the same way in each position. As most of my shooting is prone, this is the position in which I zero. When shooting in any other position I take care that I do not induce any parallax error. It doesn't always work :lol:
You should always be looking through the centre line of your scope. That is if you have your scope "optically centred". If it's not and you are still looking through the centre line you will get PA error in one direction.

ATB
Ray.

User avatar
Raj
Posts: 2005
Joined: Sun Feb 15, 2015 9:36 pm
Location: Rugby

Re: Hold sensitive PCP

Sun Mar 15, 2015 3:58 pm

For Wastrel ....
If the tree is 25 mtrs away and the target is 25 mtrs up the tree, the distance covered by your pellet is 35.35 mtrs - Simple calc. using Pythagoras. This distance would usually result in a drop if you are zeroed at 25 yards but this drop would be countered by the rise to be expected with the angle you are holding the rifle at - 45 degrees.

If you moved closer to the tree, say to 10 yards, the distance your pellet covers would be 27 yards. Then you would find that the pellet is hitting higher.

To exaggerate this, What do you think would happen if you aimed vertically up or down with a scope that had been zeroed while holding the rifle horizontal?
If you are trying this, down is easier - climb to the top of a tall building and put your target flat on the ground by the building ... As long as it is safe of course! :)
“It's the Indian, not the arrow"

Post Reply

Who is online

Users browsing this forum: Google [Bot] and 26 guests