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Grouping @ 100 yrds vs 200 yrds

slydo

Hi you all, thanks for your input
How the SAME set up : Case, load, bullet, depth etc etc can shoot great (sub MOA) @ 100 yrds but being bad @ 200 and + ?
Read that problem on couple site but I CAN'T understand it
If you get 0.500" @ 100 yrds how can you get 2.500" - 3.00" @ 200??
Except weather of course
From Québec with love ❣️
 
If you/rifle/ammo are getting 1/2" groups at 100 yards/meters, you should expect 1" at 200 yards/meters

How many groups have you shot at 200? Were the groups at 100/200 shot on the same day? What were the wind conditions while shooting at 100 vs 200?

If it were me, I'd repeat the experiment - i.e., shoot a couple groups at 100; then as soon as possible shoot a couple groups at 200 without changing anything. POI from 100 to 200 is down a couple inches.
 
Although I have experienced the increase in dispersion to the level the OP posted, nevertheless I never found a direct correlation between 100-yard groups and 200 yards in the sense that you could precisely extrapolate the 100-yard results to 200 yards by simply doubling the expected group at 200 yards from 100-yard results.

The primary reasons, at least for me, is the increase effect of environmental conditions (mirage and wind) at 200-yard, shooter error at 200 yard is magnified, and increased effects of parallax at further distances.
 
jelenko said:
If you/rifle/ammo are getting 1/2" groups at 100 yards/meters, you should expect 1" at 200 yards/meters

How many groups have you shot at 200? Were the groups at 100/200 shot on the same day? What were the wind conditions while shooting at 100 vs 200?

If it were me, I'd repeat the experiment - i.e., shoot a couple groups at 100; then as soon as possible shoot a couple groups at 200 without changing anything. POI from 100 to 200 is down a couple inches.
Click to expand...
It's not me... I do shoot 4.5"@500 just saw some post on other forums... Thanks
 
Shooting at 100yds takes the environmental and velocity deviation out of the equation and reduces the precision to primarily shooter and rifle system (muzzle pointing and uniformity of shot release). At 200 yds velocity deviation is a minor player. Environmentals are more of an issue (primarily wind) but it depends on bullet caliber and weight (also BC).

Number of shots is a major factor in determining dispersion. Also components. If you expect help you need to provide details of the components, load, setup, number of shots in the groups and possibly pictures. Weather? It all matters. If this was a generic question then the various items mentioned all come into play.
 
J.d. Popkes said:
Figured out the full length sizing thing, now you’re on to this!! :)

This issue could be a dozen things. The first reply here is a good start. More information is needed. Good luck!!
Click to expand...
It's not me ...I always balanced my commercial ammo... Shoot 4.5" @ 400
Just saw few posts on other forums that I didn't understand the WHY
 
are you shooting those 4.5 @400 with the same ammo?

Seen it with myself and a couple shooting buddies when we all got in this game of trying to shoot little tiny groups on paper.

It’s you.
 
Try this....
I've started doing my tuning at 200 yards with seating depth 1st, calm conditions of course.
I take my press and comparitor to range
All ammo is loaded long .015-.020 ITL.
Shoot 2 Did they touch? If not push bullet .003 deeper into case, shoot 2 more, rinse and repeat until you find your bullet powder selections happy place. You will see it come together and begin to open back up.
Picture for reference
105 Barts hammers N540 cci450.
1st 2 touching out the gate at .015 ITL
I made a scope adjustment 2 clicks rt and shot 2 more confirmed 1st 2 wasn't a fluke. I seated bullet .003 deeper and shot 2 more, touching only smaller, I pushed bullet another .003 deeper group opened up confirmation that my seating window was .012 ITL.Resized_20240405_104803_1732051249648.jpeg
 
slydo said:
It's not me ...I always balanced my commercial ammo... Shoot 4.5" @ 400
Just saw few posts on other forums that I didn't understand the WHY
Click to expand...

1st it is hand loaded ammo- not factory, off the shelf-

2nd it’s more than 100/200 difference
There’s equipment set up, (rifle may bounce on forearm) rear bag might have settled..

3rd wind flags should be used- to read the wind- there’s a lot more to this than just setting & shooting-

4 th - temp, humidity, pressure come into play-
Did it drop 3-7 * between either distance? Did the air get more moisture in it in 20min, or dried out??

5th - was it shot on paper or a electric target device- there is a difference

6th most short range shooters know everything comes into play at those distances- triggers, barrels, scopes, bullets, powder charges, primer choices, scope rings, ignition controls…


You should probably use the search function, save ALOT of your time, reading& watching videos, then go apply it & report back on your findings…





Otherwise thanks for adding to my list…
 
Doom said:
Shooting at 100yds takes the environmental and velocity deviation out of the equation and reduces the precision to primarily shooter and rifle system (muzzle pointing and uniformity of shot release). At 200 yds velocity deviation is a minor player. Environmentals are more of an issue (primarily wind) but it depends on bullet caliber and weight (also BC).

Number of shots is a major factor in determining dispersion. Also components. If you expect help you need to provide details of the components, load, setup, number of shots in the groups and possibly pictures. Weather? It all matters. If this was a generic question then the various items mentioned all come into play.
Click to expand...

Yep, longer is worser! IMHO load development at 100yd is a waste for longer range shooting for the reasons you stated.
 
After developing a Load with, 5 Shot group's at, 100 yds,..
I Re-Test every Load, again, on a Fairly Wind-LESS Day, using 10 Shots,. IF,. 9 out of, 10 are in, a 1" ctr / ctr Circle,..
I'm DONE ( 1/2 MOA ) allowing ONE, Gimmee,.. "Flinch / fudge up" ( Sometimes, there are, NO Gimmee's ),. So,. Happier Yet !
I mark, the Bullet Hole that, I "Think" might Be "Off", Due to, a Lack of, Concentration or, a Bad Trigger Squeeze.
On a Bigger, Harder kicking, Big Game Cartridge, I May allow up to, a 1 1/2 inch, ctr to ctr Group at 200 ( 3/4 MOA ).
AGAIN,. 10 shots. Like many Here,.. I do NOT Trust, 3 or, even,.. 5 shot, group's !
Then, Out to,. 600-700 for "Proofing" the BC's
 
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