Sights Zeroed in Distances

[josixpack]

If my .177 620fps bb/pellet gun is zeroed in with iron sights at 15 feet at what distance farther out will it be zeroed in at?

I tried using a calculator someone pointed me to but I didn’t know ¾ of the information it was asking for.

Thanks!

[sperho]

What is the weight of your pellet that you are using?  How high is the front post above the center of the barrel muzzle?

[josixpack]

7.9 grain and around 1.5 inches.

[sperho]

According to Chairgun and assuming that you are using Crosman Premier Lites (BC comes into play, so if that's not your pellet, what is?) and that I handled the iron sights appropriately, your two zeros occur at 15 and 19.5 yds.  edit:  if you are using wadcutters, the two zeros will be at 15 and 17 yds.  Flat-faced pellets lose speed much faster than diabolos...


click to biggify:

[UCChris]

Oh Chairgun. What a wonderful program.

[josixpack]

According to Chairgun and assuming that you are using Crosman Premier Lites (BC comes into play, so if that's not your pellet, what is?) and that I handled the iron sights appropriately, your two zeros occur at 15 and 19.5 yds.  edit:  if you are using wadcutters, the two zeros will be at 15 and 17 yds.  Flat-faced pellets lose speed much faster than diabolos...


click to biggify:

I just kept moving the target back and found that at around 45- 50 feet I was getting similar results as at 15 feet but was hitting high of the mark in-between those distances.  So at 30 feet I was aiming about an inch lower then the bulls eye and was getting good results.

[sperho]

Oh, you said feet, not yards. Sorry.  In any case perhaps the picture will help you understand how to use CG.

[josixpack]

Oh, you said feet, not yards. Sorry.  In any case perhaps the picture will help you understand how to use CG.

No worries... I have an indoor range set to 5 meters (16 feet 4 3/4 inches) which is the NRA BB Gun Competition target distance.