Thread: Grouping

Originally Posted by 10-Ring

That would be if you're a dial twidler would it not? Personally, not being one of the former, I've always sighted in at 200m and never had any problems out to 300m with a 7mm/08 and .308 which is about as far as I'm prepared to shoot, with the odd exception. I'd do the same with a .270 if I owned one.

I suppose it depends on the country you're usually hunting in and what cartridge you're using.

If a bush hunter or shooting 0-200m biggest percentage of time sighting in at 100m is perfered. Dial up or using ballisictic plex 100m is perfered also.

Originally Posted by deer243

If a bush hunter or shooting 0-200m biggest percentage of time

sighting in at 100m is perfered.

I agree if your shots are going to be 150m or less, preferably even 100m or less like most bush hunters would encounter.

The draw back to using a 100m zero though is that if you see the odd deer at say 300m there is about a 38cm drop. With a 200m zero it's around 5cm high at a 100m and that's not going to cause any misses. At 300m there is a 20cm drop which just means a hold on the spine or just below.

Using some common cartridges zeroed in yards.

260 Rem - 140gr

100 Yards +2.7”
150 Yards +2.9”
200 Yards +1.7”
250 Yards +1.0”
300 Yards ‐5.5”

.270 Win - 130gr

100 Yards +2.6”
150 Yards +3.0”
200 Yards +2.0”
250 Yards Zero
300 Yards ‐3.75”

7mm/08 Rem - 140gr

100 Yards +2.7”
150 Yards +3.0”
200 Yards +1.9”
250 Yards +0.6”
300 Yards ‐4.8”

308 Win - 150gr

100 Yards +2.7”
150 Yards +2.9”
200 Yards +1.7”
250 Yards ‐1.2”
300 Yards ‐5.8”

Originally Posted by deer243

.....Dial up or using ballisictic plex 100m is perfered also.

Yes for dial up. Each to their own but I personally don't have much faith in ballistic plex reticles for judging distance. Animals come in different sizes.

I nearly always zero and load test at 200. Some projectiles in certain loads will settle/shoot at 200 and beyond.

I don't think I have ever missed an animal in the bush due to an inch or so in elevation either.😆

Originally Posted by BRADS

At 200 the end of a beer can
At 300 the can itself
At 400 two cans side by side
Best I could come up with

Empty ones I hope!!!!

Originally Posted by R93

I nearly always zero and load test at 200. Some projectiles in certain loads will settle/shoot at 200 and beyond.

I don't think I have ever missed an animal in the bush due to an inch or so in elevation either.��

I have heard this before...

Eliminating all shooter and rifle error, theoretically how can a bullet shoot more accurately at range?? If you are shooting 4" groups at 100 then they will be 20" at 500.... Can someone describe the "science" behind a bullet shooting better at range?

Stability supposedly improves as distance increases. Dunno if I believe it but I have found I have shot better at 2 and 300 than I have the same day at 100.
We are talking no more than an inch or so but it seemed to improve.

Unless you are shooting multiple or very large shot strings most "smaller" groups are just a statistical anomoly. My friend just shot a 0.75" group at 250yards. He admits himself that it was a bit of a fluke.

Originally Posted by Munsey

Because never going out to 200-300 . I never seen the the point in correcting a slight left or right from centre . Thinking it's only 15 mm left but getting out it gets out of hand . Seemed more than 30mm .

The problem with zeroing at longer ranges is it introduces more variables. Wind comes into it more for one. As do temperatures and drift and all kinds of other things.

The reason pretty much everyone zeros at 50-100m is to take as many variables out of it as possible.

I've tried zero'ing further and it does your fucking head in. You're forever adjusting to try and correct a problem that doesn't exist in the first place in my opinion.

I set mine up at 100m, but I set it up to fire 1.5" high at 100m, which is a zero of 200 yards according to my ballistics app. It also makes the holdovers on my reticle line up at 300 yards, 400 yards, 450 yards and 500 yards (at 15x zoom). And my rangefinder is in yards of course.

Originally Posted by PerazziSC3

I have heard this before...

Eliminating all shooter and rifle error, theoretically how can a bullet shoot more accurately at range?? If you are shooting 4" groups at 100 then they will be 20" at 500.... Can someone describe the "science" behind a bullet shooting better at range?

Can't really describe the science accurately but I experience this with the 150 LRAB's out of my 270wsm. They shoot consistently to about 1moa at 100m but have done .5moa at 1000m. I would have done more load development if I had only tried them at 100m but shot them at 1000m the same day to see what they would do...I decided I'd stick with that load after that!

Also once tried a plastic and alloy air rifle pellet from an air rifle (pneumatic with no recoil and I could watch the pellets all the way to the target), it had a bright green plastic rear end to it and I watched it spiral through the air as it was sent down range. The spirals became smaller further out until it seemed to come right and fly true past about 20 meters.
I have since made the assumption that some bullets shot at the lower edge of the stability window may start off with a bit of a wobble, but that this is somehow corrected as they get further down range.




Sent from my iPhone using Tapatalk

I dont doubt that people can shoot better groups at 300m then they can at 100m. That is just to do with shooter technique and mind fuck. I also dont doubt a bullet may "wobble" and then straighten up, actually i sort of doubt that. But if a bullet is wobbling of course by 5cm at 100m it wont suddenly magically home back into to the POA... see picture.

Originally Posted by stug

Unless you are shooting multiple or very large shot strings most "smaller" groups are just a statistical anomoly. My friend just shot a 0.75" group at 250yards. He admits himself that it was a bit of a fluke.

What if you shot 4 of them in a row? all 3 shot groups all under .75 @250y? and it was blowing its arse off but consistantly.

I also seem to shoot better(or my rifle shoots better but I really think it is me) at 200-300 y vs 100.
As my eyesight deteriorates I find increasingly at short range threw a scope (and I am only talking 9-14power) as my eyes get tired (only a few shots) either the target or recticle is sharp but never both at 100y but is fine at 200 or more.

Yes this should be able to be fixed with eyepeice focus and parralax adjustment but for me it cant....perfect for a few shots then the eyes get tired and all goes to shit.

Yeah increase rate of dispersal can decrease with distance/stability but rate of dispersal can not, if your rifle shoots statistically significant 1moa groups at 100 meters, it cannot mechanically shoot statistically significant smaller (angular) groups past that. Mental or shooter factors taken out of the equation. Including selection bias....... which is the most likely answer for the "my rifle shoots smaller groups at long range than close range" experience


and re: zeroing at 100m - I wasn't meaning a 100m zero per se, just shooting for zero at that range. If you actually have point of impact in the right place, whether it be right on for a 100m zero or 4cm high for a 200m zero, or whatever, it is an adequate distance to do it. Of course any error is magnified at range but 100m is far enough that any error should be very negligible, your point of impact should be zeroed to within half of one click of desired location



e: TL;DR version: The bullet will not curve back towards the target regardless of how stable it is.

She has got pretty high tec this thread considering the opening posts requests good thing we answered his question early on.
@deer243 I have spent the vast majority of my hunting life hunting bush, there is a reason for the 25yard zero every old prick you talk to who has shot a ship load of deer recommends.

Its because with a 303 its also a 200y zero and a slight hold for 300.

With for example a generic 150gr 308 load a 100y zero is also "on" at 65y shorter than that its low, bush ranges are typically 20-60y.
Same load zeroed at 200y is "on" at 30Y and within 6mm from 20-45y.

Better to zero at 200y for bush.

the 25yrd zero worked with open sights.......look at ballistic app eg "pointblank" and 60ish is more like what is needed for 1.5-2" high at hundy, with scope. for what its worth my .270 sits ABOUT 2" high at a hundred and that is where it stays.

Originally Posted by Micky Duck

the 25yrd zero worked with open sights.......look at ballistic app eg "pointblank" and 60ish is more like what is needed for 1.5-2" high at hundy, with scope. for what its worth my .270 sits ABOUT 2" high at a hundred and that is where it stays.

I am looking at a ballistic app lol