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Gina1

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From my original post "Neet use for primer trays" There was a discussion that .5-.7 grain different will NOT make a different as to where a bullet will hit, and it was a waste of time to weight sort varmint bullets.
WRONG....

Yesterday went to the range, with 10 rounds. All loaded with the same powder charge, FL resized, trimmed to the same lenth, same primer, same seating depth. Only difference was 5 were loaded with bullets weighing 49.9 g and five were loaded with 50.4g.
After the first 5 were fired, I cleaned the rifle, made sure all the copper was out of it, and fired the other 5 rounds. Wind was light and variable, target range was 100 yards.
There was no adustment made to the scope and was only firing for group.

As you can see the heavier bullets hit lower on the target. Stands to reason and physics. The heavier bullet, given the same powder charge, through inertia, will not be moving as fast as the lighter bullet when it leaves the barrel. Given that the rate of drop is constant, it will have more "time" to drop before it hits the target, hence lower on the target.

OK... so what has this to do with weighing varmit rounds? Really, a hit or a miss at 300 yards, especially with ground squirrels. As I said "why not make the best round you can, when reloading"
Aslo note that in weighing all 100 bullets, there was the oddball bullet that was more the 1.0g heavier that the package label.
 

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You do know that the first round out of that perfectly clean barrel will exibit as much as 75-100 fps slower velocity than the next four. That will have a much greater affect than less than 1 grn weight in the bullets.
 
I used to think the same way....but....

Here is the kink...in the same rifle, etc, why does a higher velocity hit lower on the target and somtimes, it will hit higher. It has as much to do with barrel vibration/barrel time as it does velocity.

First, in the pic, it seems your bullet seating depth might be off or the twist isn't allowing them to stabilize. Second, If you took your top three rounds of your left target(in pic) and bottom three rounds of the right target, you would have a better group than either by itself. This also lends to the belief that the load is off and it doesn't really have anything to do with the different weight of the bullets, especially at 100yds.

Also, as Jackie said, If you started with a clean unfouled barrel both times. What was the order of the bullet impacts? This could account for the double grouping.

I have shot bullets that had a spread of just over 1.0 grns and they would all go in the same hole.

Hovis
 
Where you shooting over wind flags? were the conditions exactly the same. If you were shooting in north Texas today, you could have had a shot jump 1" right on you at any given time. Boy that wind is howling out there right now.
 
grouping

As to variations... To answer some of the questions

There are some variables, namely "me" granted. BUT in all of this you have to look at the grouping. One group is lower than the other. Yes there is the first cold bore barrel shot. It would apply to both groups. Also the Barnes Varmint Grenades are not match bullets. With Sierra MatchKing, I would have had a much tighter group. The point in all of this that I am trying to make is a heavier bullet, with the same powder charge, with all things being equal,will move slower than a light weight bullet and have more "drop" time.
Sheesh to think all this started by my trying to pass on a neet idea about using old primer trays. Give me a break.

Gina
 
Gina I don't post much anymore on this forum or Practical Machinist. I browse and try to get useful information. But,as you've seen, "No Good Deed Goes Unpunished." So, glean what you can and do your best to ignore all the "experts".
 
Gina1: Do you really think that 1 full grain in weight with a bullet is going to be affected by 50 or 60 thousand pounds of pressure, well it will not. I've tried that game at 1000 yards a number of times and they have all stayed together. And yes the primer weight does make a difference at long range. So let your rifle settle down a little more before cleaning it. Your not giving it a chance. And move back to at least 300 yards at 100 yards the Varmint will never know the difference.
Joe Salt
 
cant believe im getting drawn into this.
gina you are wrong.. what you are seeing is a rifle that is out of tune and bullets exiting the barrel at different oscillations.
it looks like what you see and are saying is happing but its not... now go tune that rifle. seating depth,change the primer, powder ect with the same bullet and re run your test.
you will see it wont matter... i have shot bullets that were going faster and hit 2" lower on the target??? and visa versa?? barrel tune or oscillation at bullet exit..??
 
adamsgt said:
Gina I don't post much anymore on this forum or Practical Machinist. I browse and try to get useful information. But,as you've seen, "No Good Deed Goes Unpunished." So, glean what you can and do your best to ignore all the "experts".
Click to expand...

Thank you.... True we all see the glass as half full or half empty. I believe I'm right. Evidence and physics back it up. No matter how large the accelerating force is (all being equal), the larger bullet has more mass, and will always move slower. and therefore more drop time. Again go back to the grouping picture.
 
Gina1 said:
No matter how large the accelerating force is (all being equal), the larger bullet has more mass, and will always move slower. and therefore more drop time.
Click to expand...

All being equal - yes. But, what if they start on a different trajectory?
 
RLHBUSL said:
All being equal - yes. But, what if they start on a different trajectory?
Click to expand...

Sheesh.... that is why it was a "group" shot. To try and average out the "me" factor.
Sure you might have a one time deal of different bullet weights going through the same hole. But is that the bullet or the shooter. Only a group shot will show it to be one way or the other. Try it yourself. and let me know your results.

Gina
 
The originol poster comes on this site, and stated a conclusion. All we did is state that there are a miriad of other things that could alter his hypothesis.

Would it be prefered we just let him be happy in his ignorance.

On any of my Benchrest Rifles, at 100 yards, I can move the group as much as the width or height of the mothball by simply turning the tuner. .........jackie
 
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Gina1 said:
Evidence and physics back it up. No matter how large the accelerating force is (all being equal), the larger bullet has more mass, and will always move slower. and therefore more drop time. Again go back to the grouping picture.
Click to expand...
Two points:

The first is that what you say is true in a vacuum. Once you introduce air (drag), it is a whole different world. Sadly, that's our world

The second is that where a shot prints (high or low) depends on two other things, the orientation (vertical angle) of the muzzle at the moment the bullet clears the bore, and the position of the muzzle in the vertical plane. Why we tune.

There is an old adage, "test one thing at a time." While often good advice, the problem with that one comes up when you cannot, in any practical way, isolate what you're testing. I those cases, you are apt draw wrong some conclusions, esp. if you generalize.
 
Gina 1, If you run a ballistics calculation (JBM Ballistics) plugging in the different bullet weights 0.1 grain at a time with everything else the same. You can then see the change in drop caused by their difference, without all the other physical causes. The effect is marginal up to about 400 yards after that it becomes much more apparent.

Big K
 
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OK guys.... I give up. We agree to disagree. I'll still continue to weight sort my bullets. Each to their own.

Gina
 
Gina1,
I also weight sort my bullets that I use in competition and I don't condemn you for doing it with the varmint bullets either I believe the more consistent you can be the better and that goes for all things in the shooting world from your loads to yourself and everything in between, with that being said I have to agree with some of the others that your rifle is out of tune, both groups show that. I am not trying to be troublesome just trying to help, I don't post on here much, spend most of my time on 6br but the loads and or the rifle are out of tune. Tune your loads so they are consistent then load several with say 49.9 or whatever load several of them at least 20 then instead of loading the 50.4 like you did last time, randomly out of the un weighed box of bullets load at least 10 or 15 more then you do of the weighed bullets, now to try and prove your theory shoot two or three fowlers at a fowler target with the extra unweighed lot then put 5 of your weighed bullets on paper and repeat with the un weighed one and continue until your finished, do this at at least 300 yards, I believe you will fid your weighed will shoot a little better,... how much?... who knows give it a try and find out. Just a side note I would personally take serious consideration in anything Jackie Schmidt has to offer, his long standing records speak for themselves.
Wayne.
 
Gina1,

What we are telling you is fact. You can very simply prove it to yourself. Start at the low end of the powder charge with your rifle and start shooting three shot groups. Go up in powder charge .5 grn at a time. If your theory is correct, then the groups will always print higher. But what you will see, is the groups move in one direction and the start going in the other in the verticle plane. If you shoot across a target you will see a wave form. This is showing you where the muzzle is in relation to bullet exit. Somewhere around a peek or valley is where the gun will shoot it's best with that combination. This also becomes apparent when tuning using Boyer's method. Changing only the seating depth will have the same effect.

Get Boyer's book and read about tuning. What we are talking about is common knowledge in Benchrest, we all learn it the hard way though.

Hovis
 
As I said in your original post, if you believe it helps it will. It certainly won't hurt anything to weight sort and it's your time, have at it.
 
Thank you for the information on Tony Boyer's book. I read the reviews and it looks like it contains much knowledge on BR shooting. YES it could be what I'm looking for. I'm always looking to improve my shooting. I'll be ordering it this coming week.
Thanks again

Gina
 
steve stanley

Considering your answer in my original post (neet uses for old primer trays) there was no need to to repost your same comments in this thread.

Gina
 
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