Just watched this interesting video from Reloading Weatherby. His 7PRC wasn’t getting much better than 1MOA grouping at 100yards, but was on target out to 1000. Interesting. In the video, he is making that case that for hunters, the pursuit of the smallest grping at 100 yards isn’t as valuable as accuracy at distance.
I know for my 7PRC I get .75" to ~.85" grps at 100 yards, but its a laser to 800. He also mentioned that he has 6.5PRC that is a nail driver at 100, but not at 500.
A bullet is not a heat seeking missile. A rifle’s dispersion cannot simply fix itself by adding distance. The natural dispersion of the RIFLE will ALWAYS get worse with distance.
HOWEVER, a 1 moa gun at 100 with a tighter variation in velocity such as 5fps SD will shoot a BETTER group at 1000 than a 1/4 moa gun at 100 with a 20fps SD.
Thats not because the RIFLE is somehow good at distance but not up close. That’s nonsense. But the better AMMO contributes more to the group at 1000 than the the natural dispersion of the rifle at 100.
At typical hunting ranges, the same is not the case. I’d rather have the 1/4moa gun with worse ammo than the 1” gun with better SD in the ammo.
The Hornady podcast from just a couple of days ago goes into this at length. It’s about the rumors / old wives tales of ballistics. Quite long but a good listen
Im not really good at reading tone in short text like these, but I think @backfire was coming in hot here . Not sure if that video got you mad, but you’re usually so even keeled in your responses.
I’m with you as the math doesn’t add up to me. I’ve never had a rifle be good at 100 and bad at distance, but I also know that the 7PRC is so ballistically good that it masks shooter flaws so I couldn’t dismiss this outright. I thought, maybe there is something here… guess not lol.
BULLET CONSTRUCTION: As a bullet passes through a rifle barrel, it spins around the dimensional center. Much like a properly balanced tire, a well-balanced bullet will spin properly and smoothly. An unbalanced bullet will spin around the dimensional center until it leaves the barrel, then it will wobble in flight as it switches its axes to spin around its center of gravity. When the bullet stabilizes, it is said to have “gone to sleep.” This only takes only milliseconds, but its effect on accuracy is clear at even 200 yards. Target bullets need to withstand pressure and heat, and be well balanced. This is most often accomplished by using a lead core and thin jacket. The lead core is balanced by uniform structural nature and the jacket must also be balanced.
If this is true I could see accuracy getting better past 100 yds as it may take a little more time for the bullet to stabilize itself and “go to sleep”
Re: group size improving at longer ranges starts at 30:20. Going to sleep is sometime before that.
In terms of RW’s video, I agree with his main point which is that we focus way too much on shooting a bug hole Group at 100 yards. That’s done for a variety of reasons and part of that is industry tells us that’s what’s important. But we’ve even discussed the issues regarding how one actually measures that on this forum, and the manufacturer’s ability to just make numbers up.
The video series that he references from Little Crow goes into that also several months ago. He ran ballistic software and looked at the ability to place a hit on the vitals of an elk at 600 yards. He then varied different variables to see what had the most impact on improving those odds. Small group size was very low on that list in terms of ranking.
I agree with Jim like I am some expert. ha. But shooting is like many engineering disciplines and the same statistical behaviors of bullets is not different that so many other engineering problems be it electronics or mechanical design to predict failure. It is the statistical chance of failure based on your variables that matter - in electronics it was mainly voltage and temperature - four corner analysis. In part design it is fem finite element analysis. And ballistics the same. So you cannot cheat the variables - they make that point in the podcast. They say some variables cannot be known or controlled - same in electronics (my field). But you can spend a lot of time and money understanding what you can improve. My projects would make millions of modules for customers. We kept statistics on every one we made but even that is only as good as your test. Anyways I digress. I guess to summarize- you cannot get something for nothing. Time - money - skill - knowledge- all of them but no way that a statistical significant sample at 1000 yards is better than 100 yards. If you have enough data they should be the same give all variable the same. But humans are part of the variable and that is the worst tolerance of them all. Us. ( oh and stupid air - wind)
Bottom Line: This effect is no different than firing (e.g.) five 3-hot groups at the same target; the groups will vary in size - sometimes very close in size, sometimes not, sometimes very similar in center of the groups and sometimes not.
If someone shoots a 1 MOA group at 100 yards and then a .7 MOA group at some greater distance, it’s only because of the normal variation on accuracy and precision over a statistically valid sample size. That second group would have been equally smaller on the 100 yard target as it was on the further target.
There’s no special effect (gyroscopic, wobble, etc) the could cause a bullet to veer away from and then back toward point of aim between the muzzle and the target, much less repeatably and predictably. That’s just the physics and mechanics of projectiles.
This season, I was working to find a good handload in one of my 308s and it was proving a challenge. I got it to group well, but only with a lighter bullet, and for shooting in the wind, I wanted to have a heavier bullet option.
Well, after trying quite a few, I was digging through my “loaded but not fired” collection of bullets on the shelf, and found a load I had done for another 308 years ago, but got rid of the rifle. Pretty standard load, 155 AMAX, Varget at about 2820, so fine for hunting.
Went to the range, shot three at 200 without adjusting my scope from the current settings for the 125 round setup.
Group was solid 1.750 at 200, 8 inches low, and 8 inches left.
Adjusted to be on at 200, and then added elevation to be on at 300.
Shot 3 at 300, solid 3.0 group, added elevation and shot 3 at 400 with a 4.75 group, then 3 at 500 and shot a 5.0 group.
Good enough…went home, pulled one of the original bullets, dumped and remeasured the powder charge, measured and checked the seating and COAL, loaded 20 and that is what I have been hunting with this year.
Over the past months I have randomly dialed my scope for one cold shot at 300, then one at 400, then one at 500. Those have all been within 1 MOA cold bore everytime, that tells me that the load and weapon have repeatability under different environmental conditions and over time…from one hunt to another.
So, I look for repeatability as the measure of a hunting load. I chase groups, have always done it because it is part and parcel to handloading, but repeatability/predictability is more important to me.
Good luck.
. Not sure if that video got you mad, but you’re usually so even keeled in your responses.
