hold over/under

[clone]

ok heres a daft but practical question

 

 

i have a mil-dot 3-9x30 scope set at 30 yards when shooting at 30 yards i put the centre of the cross hair on taget, and when shooting at targets further away i have to aim above the target to allow for the pellet drop but when shooting less than 30 yards where do i put the cross hair?

[Dexon]

The best way to find out is trial and error, mark out the distances and try it, using your millidots as a guide. Here is an mathamatical example:

 

Gun power = 11.8 ft lbs

Pellet Weight = 14.3 grains

Zero = 30 yards

 

20 yards .75" high

10 yards .8" high

35 yards 1" drop

40 yards 2.5 drop

[SNAKEBITE]

Paper punching sounds labourious and time consuming, and it can be if you don't try and put some fun into it.

However once you have done it it will improve your confidence and your knowledge no end.

[1 of 5]

Too many variables to answer that question - scope height, mag, calibre, pellet type, BC, power.

Download Chairgun and have a play around - it's free.

http://www.chairgun.com/

[roblade]

Too many variables to answer that question - scope height, mag, calibre, pellet type, BC, power.

Download Chairgun and have a play around - it's free.

http://www.chairgun.com/

thats the way to do it in theory, and a very good way it is

 

but me i prefer the hands on approach, if your able to do it.

 

place out a two targets every 5 yards, then get a nice comfy shooting position as you would shoot in the field.

 

5 shots at one target all the way back aiming at dead centre on each.

 

then back to the first target placing x hairs on target note where abouts they strike on the scope (mill dot or part of cross hair).

 

then place the new aim point on the centre of the target and you should be hitting bulls all the way down.

 

for things like this, its so much easier to join a club and have a good couple of hours on the range getting used to the rifle.

 

ROB

[BountyHunter]

Too many variables to answer that question - scope height, mag, calibre, pellet type, BC, power.

Download Chairgun and have a play around - it's free.

http://www.chairgun.com/

Just went and got the mobile version:

 

What is BC and what is the Muzzle Velocity for a PCP 12ftlber?

 

BH

[Axe]

You'll need to get your rifle on a chrono which will give you the Muzzel Velocity and the ft/lbs. Set the grain weight of your pellet (for instance Accupels are 14.31) and enter the ft/lb's (example 11.8) and chairgun should give you the rest. BC is the Ballistic Coefficient.

[BountyHunter]

Thanks....Ballistic Coefficient.. :thumbs:

[Axe]

Ballistic coefficient

A measure of a given projectile's ability to overcome air resistance in flight when compared to a standard projectile used to calculate ballistic tables. The BC will always be less than 1 and the higher the number the better. For example a BC of .39 is better than one of .142, especially as the range increases.

 

Have you seen the Forum Dictionary

Edited November 18, 2005 by Axe

[1 of 5]

A good .22 pellet will have a BC around the 0.030 mark whereas a good .177 will be 0.024 or so. Bad designs can be down around 0.012 and you'll see from chairgun just how quickly they shed energy downrange compared to the good ones. The same pellet will have different BC values in different barrels though not usually by a great deal. You can work out the bc with two chronos. One at the muzzle and one downrange. Failing that just one at the muzzle and measuring the drop downrange will allow you to get close. Chairgun has a feature that allows you to enter the muzzle velocity and drop and will calculate the BC.

[SNAKEBITE]

I do like chairgun but nothing beats doing it for real!

Infact now i do not use a laser I have not touched chairgun for months.

[wacker]

If yours is .177 & using std mounts your first zero should be at 15yds & again at 35yds, so between say 8-10yds aim a tad high, after 15 start to aim low, 30yds crosshairs should be just under and bang on at 35yds, after that you'll have to start aiming high. At 45yds to hit a target with a gun doing around 11.5ftlbs it should be .9 of a mill dot high. Hard to explain when you write it but if you get

a target & shoot it at 8,10,15,20,25,30,35 & so on you will see what your gun is doing in terms of tragectary & aim accordingly.