Bullet drop question

clivej

What is the bullet drop of:
1. A 22 sub @50y
2. A 223 50g @100y

Scope NOT zeroed and without getting too technical about the 22 sub and 223 coefficient etc.

I was looking at a balistics calculator and I think the 22 sub drops 2.25 inches @50y and the 223 drops 2.25 inches @100y is that right???

newby.204

Tbh you cant really answer that question until you have zeroed the scope. i.e. you need a specific distance at which the crosshairs of your scope effectively cross the path of the round before you can talk high or low. now every round will have a flight path and drop off at certain ranges that is predetermined however is also affected by bullet weight)

tommy and johny both have .22lr rifles(both are using subs)

tommy is zeroed at 75yrs and johny at 125yrds

both firing at 100yrds
-tommy's rounds land 2" low(of poa)
-john's rounds land 2" high(of poa)

i dont know whetehr i have explained myself well if i havnt ill come back tommorrow hope ive helped

Rovi

Forget about sights, and just imagine the barrel set up exactly parallel to the earth's surface, and allow that for the purposes of this example, the earth's surface is effectively flat.

According to the Sierra Bullets Infinity Suite:
A 40gr .22LR going 1050fps will drop 4.23 inches at 50 yards.
A 50gr .223 Rem going 3140fps will drop 2.0 inches at 100 yards.

Is that what you were looking for?

clivej

Rovi wrote: »

Forget about sights, and just imagine the barrel set up exactly parallel to the earth's surface, and allow that for the purposes of this example, the earth's surface is effectively flat.

According to the Sierra Bullets Infinity Suite:
A 40gr .22LR going 1050fps will drop 4.23 inches at 50 yards.
A 50gr .223 Rem going 3140fps will drop 2.0 inches at 100 yards.

Is that what you were looking for?

Thats exlactly what I wanted thanks Rovi.

I'm going to zero the scope so that the gross hairs are centred ie NO up/dpwn elevation or left/right windage. Then mount the scope and dial in the drop for the bullet say for the 223 - 2" @100y, plus the scope height -- I have some 50g 223 rem to try.
Just wanted to see how near I could get to the bull @100y with a new rifle and first bullet through it, allowing for the windage as not counting.

Vegeta

clivej wrote: »

I'm going to zero the scope so that the gross hairs are centred ie NO up/dpwn elevation or left/right windage.

What do you mean NO elevation and windage, do you mean counting the number of clicks (say its 200 from one max to the other on both turrets) and placing the scope in the centre of that click range i.e. 100 clicks?

Then mount the scope and dial in the drop for the bullet say for the 223 - 2" @100y, I have some 50g 223 rem.
Just wanted to see how near I could get to the bull @100y with a new rifle and first bullet through it, allowing for the windage as not counting.

Don't neglect scope height. EDIT: cool I see by your edit you haven't forgotten. Good man. Let us know how you get one. I love zeroing new rifles, good times

Jonty

Vegeta wrote: »

What do you mean NO elevation and windage, do you mean counting the number of clicks (say its 200 from one max to the other on both turrets) and placing the scope in the centre of that click range i.e. 100 clicks?

I think thats what he means. I wouldn't bother TBH. This assumes that the barrel and rings are true when more often than not they are out of alignment??

Might just be better to get the scope on paper at 25yds and just take it from there....

clivej

Vegeta wrote: »

What do you mean NO elevation and windage, do you mean counting the number of clicks (say its 200 from one max to the other on both turrets) and placing the scope in the centre of that click range i.e. 100 clicks?

NO I mean to zero the scope in a "Vee" block looking at a vertical line, plumb line hanging will do, at about 50m or more.
Do the elevation first by rotating the scope through 180' and see if it is still on the verical line, if not adjust as needed by going back and forth through 180' until all is true.Then repeat for the windage but now with the scope windage line vertical.
After you will be able to rotate the scope through 360' and the cross hairs will not move off a viewed point.
Then the scope cross hairs will be truely zeroed i.e. the cross hairs are in the exact centre of the optics.
Now mount the scope on the gun.

NOT all scopes arrive, as new, with the cross hairs centred.

Vegeta

clivej wrote: »

NO I mean to zero the scope in a "Vee" block looking at a vertical line, plumb line hanging will do, at about 50m or more.
Do the elevation first by rotating the scope through 180' and see if it is still on the verical line, if not adjust as needed by going back and forth through 180' until all is true.Then repeat for the windage but now with the scope windage line vertical.
After you will be able to rotate the scope through 360' and the cross hairs will not move off a viewed point.
Then the scope cross hairs will be truely zeroed i.e. the cross hairs are in the exact centre of the optics.
Now mount the scope on the gun.

NOT all scopes arrive, as new, with the cross hairs centred.

Have to say clive I have never heard of this before.

Are you just doing it to try and get as close to dead on as possible with the first shot.

What you doing to ensure mounts are straight and true? You going to lap them?

milkerman

Clive, what about the inbuilt parallax adjustment in your scope? i.e. Will you need to include the distance to your stringline as a variable in your experiment?
I posted another thread recently on the effect of adjustable objectives. I also asked down the club- I still havent sussed it. This sort of experiment might initially seem pointless but the experimenter will know a hell of a lot more about his gear at the end - and that should help in placing bullets Exactly where they are supposed to go at various ranges.
Dammit Clive now you have me thinking of how best to secure a scope so it can be rotated without drifting off it's linear axis. That will be difficult as even minute variations will be magnified over the range you are focussing at.

clivej

Vegeta wrote: »

Have to say clive I have never heard of this before.

Are you just doing it to try and get as close to dead on as possible with the first shot.

What you doing to ensure mounts are straight and true? You going to lap them?

Not going as far as lapping the mounts and only using the mounts as they come. They can be off as I found out before 6" off the vertical then turned them around and they were just 1" off the vertical.

Trying to get as near to bull as possible on the first round at the target through the new gun.

I will put up photos of the scope in a Vee block later as I do the scope cross hair zeroing

newby.204

thought someone might be able to explain what i ment.............

Vegeta

clivej wrote: »

Not going as far as lapping the mounts and only using the mounts as they come. They can be off as I found out before 6" off the vertical then turned them around and they were just 1" off the vertical.

I will say be careful with the mounts

My brother had a set and they scratched his Zeiss scope on the tube, superficial only but knocking lots of euro off resale :mad: Put scope into them and tightened them lightly, was rotating the scope to get crosshairs parallel, uneven internal surface left a nasty scratch on the scope. If they were lapped it would not have happened.

Also if they have left right (windage) adjustments (tightening screws on both sides) don't underestimate the amount this effects your first shot.

Brother put same scope on a .243 and his first shot missed a 3 foot by 3 foot board at 30 yards due to this. Then he had to call me in to sort it, he ran out of windage adjustments even trying to get on the board. I had to take scope off and start from scratch.

Keep us informed, really looking forward to the report.