Quantify Bullet Weight Variation Effects?

[Grump]

Re-read the bullet prep/sort/processing post AND thread in the on-line book or whatever you want to call it.

So, for various calibers, just how much difference in point of impact, or change in 5-round group size, will a 0.5-grain/0.323994550000002 gram change or range in bullet weight give us? At 500 yards? At 800? At 1,000?

Just wondering, but it's going to become important in my next reloading session.

 

[leadbullet]

Re: Quantify Bullet Weight Variation Effects?

not enough that your wobble, wind call, etc won't exceed. measuring that much of weight variation is assinine.
hope this helps you getting off the loading bench and go shoot instead.

 

[Greg Langelius *]

Re: Quantify Bullet Weight Variation Effects?

I don't weigh bullets.

 

[timelinex]

Re: Quantify Bullet Weight Variation Effects?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grump</div><div class="ubbcode-body">Re-read the bullet prep/sort/processing post AND thread in the on-line book or whatever you want to call it.

So, for various calibers, just how much difference in point of impact, or change in 5-round group size, will a 0.5-grain/0.323994550000002 gram change or range in bullet weight give us? At 500 yards? At 800? At 1,000?

Just wondering, but it's going to become important in my next reloading session. </div></div> go to your ballistic calculator and change the weight of the bullet.. Maybe change the bc as well by .02 for every .01 grain diff. That will give you your idea of how it effects things... I'm guessing very minimally

 

[MALLARD]

Re: Quantify Bullet Weight Variation Effects?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: attherange</div><div class="ubbcode-body">not enough that your wobble, wind call, etc won't exceed. measuring that much of weight variation is assinine.
hope this helps you getting off the loading bench and go shoot instead. </div></div>
+1 , only at extreme long range , like 1500y , will bullet weight matter. Variations in bullet weight is going to effect your ES/SD , extreme spread and standard deviation , which will effect your TOF ( time of flight) which will effect everything else.

 

[Grump]

Re: Quantify Bullet Weight Variation Effects?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">I don't weigh bullets. </div></div>
Neither do I, and I'm looking for observed (not calculated) data to keep me there.

While in between radio calls and patrols in a slightly drafty guard shack at/near 40-Mile Canyon on 12-hour shifts, my Dad weighed several hundred USGI M72 bullets back when I was filling diapers. The variations in the whole batch were something like 3 grains, and he reported getting slightly better than M72 ammo results out of his NM Garand at 600 with his reloads.

He also reported the then-newish Sierra 168-gr "International" bullets were almost always +/- 0.1 grain in any box of 100, for a total spread of 0.2 grains most of the time, occasionally a total of 0.3-0.4 because of the rare box with 1-3 bullets that far "out" of average.

Maybe someday I'll test this using a .6-MOA or better gun and load and report back to you "run the numbers" guys. I would do it at 500 and beyond, and mainly track the vertical.

Or maybe not.

 

[Greg Langelius *]

Re: Quantify Bullet Weight Variation Effects?

I used to.

Then one day, I mixed up my batches, and things went completely the opposite of the expected.

I learned something that day. I learned not to weigh/measure bullets.

It's not consistency of the components that generate my inaccuracies. Component makers' quality control standards are in the right place, cost vs consistency.

It's what we do with those components, and with the resulting ammunition, that makes or breaks our scores.

Most Indians can shoot most arrows well enough not to starve. Some can do better, some worse.

Greg