Bullet weight sorting

Was up the range doing load work for my new .338 Lapua over the weekend.

My aim was to run in the barrel with a cheaper load using a mid charge under a Lapua 250gr Lock Base then to carry out some initial load testing using AR2225 and Hornady 285gr ELD-M The Hornady sure didn't break any records for accuracy. Only 3 shot groups and very early days.

When I got home I decided to weigh the bullets I had left (and some others) as you can see the Hornady which were the most expensive bullets weighed were the worst for consistency. So when your bullets are as inconsistent as this the best powder scales wont help you. By culling a few bullets your chance of smaller groups especially at a mile will improve. That very light Berger would screw you up at long range So will I weigh my bullets from now on well unfortunately yes.

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What did you weigh them with?

Now I'm afraid to answer yours might be bigger than mine. PACT BKII

Im no expert in this but sounds like you are looking in the wrong area for a problem. 0.1 of a grain is 0.04% difference in weight. 1 grain is 0.4% difference compared to the 250gr rated pill, even less compared to a 285. Sure it will have some effect but its probably not worth thinking about. 1 grain spread in a 55gr .223 pill is almost 2%.

I FL size. Weigh my powder on a balance scale to the same level and seat my projectiles and most are +/- 0.02mm and get 1/2moa groups when I do my part for my 260 and 308. I understand everything you can do will help improve your groups but if you think about how much of a difference that variance in weight is. How much time its going to take you to sort it into weight batches, will you shoot all weights or discard the extreme spread? What distances are you shooting at and what level. ie national competition etc?
would playing with charge weight or seating depth first be more worth while?

Ah I didn't read the mile part.
I would discard the ones well outside of the mean and use them for load development at closer ranges.

I think you maybe causing yourself extra headaches Jeremy. With a jacketed bullet there will always be some variation because of the lead. That’s why there is this new big interest in solid copper bullets for elr. The 285 from what I’ve heard don’t seem to work in every rifle. I am going to start doing some group testing and will ge at sparrowhawk this weekend so I might try a grouping at 1000m + with the 285. Like I said to you earlier from everything I be learnt from the 338 the 250 and 300 lapua scenar are the easiest to get to work in most rifles. Ive never weighed any of mine and only seen about a foot of verticals dispersion at 2km. Wind is the hard part.
Good luck with it. Try a 10 round load development. 7 round ladder test at .5gr increments as smaller amounts amount to stuff all in a 338 lapua case. Shoot them to same point over a chronny. Take the velocity flat point at the desired speed and pressure showing on the primers. Then load 3 and you should have single digit sd and a decent group. The 338 may take a bit of time to get shooting groups less than 1” if you normally shoot light calibers. They exaggerate everything in your shooting fundamentals. In elr a 1/4” group with a 50 FPS velocity spread will hurt vertical accuracy at 1 mile

You’d laugh at this, I was at an nzda meeting last night and called bull shit. A guy was selling a Weatherby hunting rifle in 338 win mag. With a box of 200gr Winchester factory so ammo. And a vx2 scope with 2 hold dots. Reckoned the guy who owned it shot a 8” gong at 1000m in 3 shots. He must be either the luckiest or best shot around. I’m thinking neither. But I maybe wrong. Bet it was probably about 300m as he maybe didn’t have a rangefinder.

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I’d be happy if I can do this with the 338. Shot this just before heading to the alpine match the other week to check my ammo I had just made on the range by my house. Target was 750m. Shot with my Dan hardy 300win mag. One of his early ones built. His action and barrel in a senator stock using 208 eldm.

Also Sparrowhawknz is hosting the next long range match. 25-26 August. Same weekend as gunslinger we’re going to do there before they folded. So if you have airfares booked. Nick will be posting info on his website next week to enter.

Using cheap electronic scales (anything less than $ 1000) for sorting projectiles is a waste of time.

Have a look at the differences between a force restoration balance and a strain gauge type scale...

I have a little experiment for you.

Go ahead and weigh your projectiles. Label some bags carefully, and store the projectiles in them.

Come back an hour, or a day or a week later and weigh them again. See how much consistency you get...

Litz (Applied Ballistics) has done quite a bit of research on factors affecting accuracy, and you are better off:

1) buying projectiles that come from a manufacturer that has better quality control i.e. Berger
2) if you have the time and patience to sort projectiles, do it by bearing surface length.

[QUOTE=ebf;704583]Using cheap electronic scales (anything less than $ 1000) for sorting projectiles is a waste of time.
[/QUOTE

What he says mate the accuracy of the bbk2 is .1/.10 grains for under 300 so wasting ya time mate.

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Hi Cowboy I have picked up a box of Lapua Scenar 300gr to try on my next range session. It is very early days with only about 50 rounds down the barrel so when it settles down I am thinking things will improve. A 3 shot group of .3" is not bad but I am sure 10 shot groups after at least 100 rounds will start to show the potential of the Hardy barrel. I would love to get down for the Sparrowhawk shoot however I am attending an Accuracy First 3 day school in Texas in September so funds are going towards that.

Ebf I don't agree with your views on the scales. That it shows some manufacturers projectiles more consistent than others is proof that there is accuracy there. I will take you up on the challenge and keep you all posted. I agree with your thoughts on quality control the results show Berger are very good however isn't that a perfect bell curve for the Lapua Lockbase.

Thanks for both of your thoughts guys

@Dermastor, there is accuracy in projectile weight for sure, but there are other factors which may have more impact...

Simply because you think you've seen some consistency in weight measurements does not mean that is what actually causes the accuracy. It may well be that those projectiles also had a similar bell curve in terms on bearing surface and/or several other criteria...

An old rule of thumb in metrology is to use an instrument with prescision of one decimal place more than what you are trying to measure. So if you want to measure length to a thousands of an inch, you should be using a tenth micrometer for decent results. Same thing applies to weight measurements. You will not get repeatable, accurate measurements weighing to 0.1 grain with a scale that has a prescision of 0.1 grain. Add to that the tendency of strain gauge scales to drift (by up to 0.4grain), and you will start to understand my waste of time comment.

Looking forward to your results, and have fun on the course, TH is well worth listening to.

The weight consistency is well inside one grain, even if we include the Berger "outlier".

0.8 grain difference is about the weight of a drop of water. Most scales should be able to deal with this, maybe not accurately, but scales are good at picking up differences regardless.

So I reweighed the Lapua Scenar 300gr bullets. Yes there was a different result the second time around, however a similar trend of weight distribution remains and to say it was a waste of time ignores that fact that I'm not that interested in the actual weight but how close they are in weight to each other and the 2 weighing's show this result. We all have budget restraints budget so make the best with what we have

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@Dermastor,

Thanks for the interesting posts.

So... if your budget is fixed but your time is not... you now scrape lead out the bottom of all bullets, in a concentric fashion, until they are all 299.6 grain. Doable. And the jury is out forever debating if it will be worth it. But your results have the final say.

Don't know about scraping the bottom of your bullets. I was told never to touch the bottom as this was the most likely to effect accuracy!
Case in point being two bullets. One with a small dent to the head and the one with a small scratch across the base. The second one was the flyer. You can try this. I have never bothered as there are so many factors that come into play in the accuracy game.
But I'm always very careful when seating the bullet not to scratch/scrape the base.
Is it doable if your a true bench rest shooter? Yes/No?

Himmmmmmmm probably not scrape the bottom of the bullet as its brass but maybe verrrrry carefully drill small holes until they weigh the same. Yeah nah, but I will weigh them and put aside the ones that fall towards outside the nice bell curve thingy. Hey it can't make them less accurate I need all the help I can get.

You have bigger problems than bullet weights.

Make some of your very best ammo with all the projectiles exactly the same weight & some with the projectiles with weights all over the show, say enough for 5 groups of each.

Shoot the groups & see which has the best average size, make sure you do it in very good consistent conditions otherwise don't bother.

A quarter of a gust of wind you miss or breaking your position will have more effect on group size even with big high BC bullets zipping along than a few tenths of a grain here or there, same with powder weights in big cases

Thanks for your input Greg I agree and disagree.

Yes its true we can make 1/2moa ammo and let ourselves down with lack of training and bad shooting habits or misread the environment. However the opposite is true if you start with 1 1/2moa ammo no amount of training will help you make those long hits. That is why we strive to make the best ammo and practice our sport. Weight sorting bullets will only gain very small improvements in ammo accuracy which is why brass is already weight sorted into batches, neck turned, flash hole uniformed etc and neck tension is monitored while loading.

Powder charge consistency is probably my biggest challenge at the moment not being able to afford a Prometheus. Its the flyers caused by bad loading components and procedures as well as crappy shooting position or bad wind reading that we are always trying to eliminate. By the time I get all my crap sorted I will be too old to see the targets.

I envy the young guys out there just getting into the sport 30 yrs ago we just didn't have the gear you can get now or it was soo expensive getting it wasn't possible.

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Originally Posted by Sideshow

Don't know about scraping the bottom of your bullets. I was told never to touch the bottom as this was the most likely to effect accuracy!
Case in point being two bullets. One with a small dent to the head and the one with a small scratch across the base. The second one was the flyer. You can try this. I have never bothered as there are so many factors that come into play in the accuracy game.
But I'm always very careful when seating the bullet not to scratch/scrape the base.
Is it doable if your a true bench rest shooter? Yes/No?

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@Sideshow

Yes, not touch the sides of the bottom, was talking more of rotating something like a rounded, sharpened screwdriver around in the exposed lead base. But it seems a no-no based on experience of some.

Saw someone was selling a glorified pencil sharpener to trim the meplat sharp on FMJs. Trimming them all sharp (blunt vs sharp does make a difference far down range, so you can't leave the heavier ones blunt tipped), and then trim further back as per weight requirement would seem the way to go then.

The nagging doubt at the back of my brain somewhere...is the consistency of the scales used by @Dermastor. He needs to be really certain on that one before taking that pencil sharpener to his projectiles.

@Dermastor, what discipline are you shooting ? benchrest, f-class ?

I mainly shooting long range steel with rifles from 6.5x47 Lapua, 7mm Rem Mag and recently .338 Lapua. I compete rather averagely in things like the NZ Mountain Challenge and some of the Alpine Long Range matches I am also a member of Akarana City so F-Class in the summer for practice. Lots of fun.

@Cordite that meplat trimmer dose sound the way to if you did want to trim your bullets. @Dermastor sorry I was talking about bullets not cartridges my bad. You had me when you said trimming the brass from the base of your bullets...I'm like :wtfsmilie: :thumbsup: didn't realise you where talking about your brass cartridges.

I reckon you’re thinking way too much :)

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Originally Posted by Gibo

I reckon you’re thinking way too much :)

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Thank's @Gibo... (O: He heh heh!

While thinking too much I just masking tape "paper" patched thirty 155grain copper electroplated boolits from Gunworks, to go in my No 4 two-groove. Bore slugged at .304 at throat and muzzle alike, grooves .317". Bare bullets measure .307" and are patched to .316". I'll shoot some patched, some bare.

The .307 unpatched ones will likely do just fine, something to hope for as I just managed not to slice my fingers with the craft knife doing those thirty. Even if my job was minimum wage it would not be worth all this fiddling to make cheaper bullets... but it's the fun.

Just realised... I forgot to weigh them all first. Drat!!!

Jeremy I weighed a few of my 285. About 20. Most were 284.8grains with a few others the top 285 and the bottom 284.6.

I once weighed a few Nosler 7mm ballistic tip (and measured) to see if they were the real thing.

My bullets straight from the box:
140.1 gr 2
140.2 gr 8
140.3 gr 1

Bullets given to me "These are 140 grain ballistic tips mate !"
139.8 gr 1
139.9 gr 4
140.0 gr 4
140.1 gr 2


To check precision, you can just measure one bullet 10 or 20 times (I haven't done that).

To assure I'm not getting variation between one reloading session and the next, I weigh my "control" M8 nut at the beginning middle and end of each powder throwing session. It weighs 44.3 gr. I only thought of this two years ago. In 12 reloading sessions (36 measurements) it has weighed exactly 44.3gr every time. This is on a chargemaster so its not $1000 equipment. There are some standard methods you follow to get stable performance when using the scales, but essentially, they are precise and stable to within their stated specifications within and between sessions.

If you want to be a better long range shooter :

Shoot more

Learn to read wind

Shoot more

Learn a version of the marksmanship principles and apply them

Shoot more

Learning wind and improving shooting technique depend on having the most accurate equipment available.

So, even if a variable gives minor improvement in consistency it may be worthwhile if it enables better feedback when you make errors.

Bullet weight variation will affect the muzzle velocity and the ballistic coefficient but as one goes down the other goes up. :)

I ran numbers in JBM for a 338LM shooting 285gr ELD-M at 2800fps and for my 7mm08 shooting 140gr NBT at 2800 fps.
Then I ran it again for 284.5 gr and 139.7 grains, adjusted the velocities (2 or 3 fps) to give the same muzzle kinetic energy.
Sight height was 2 inches and zero range was 100 yd. Atmosphere was standard. Wind was 10 mph.

Looking at drop at close to the max supersonic range for each cartridge:
338LM 1500 yd: 285gr 750.6 in vs 284.5gr 750.1 in
7mm08 1000yd: 140gr 398.7 in vs 139.7gr 398.5 in
Windage was also less than 1 inch different.



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This is something to add , take it as you will ? Bullet Bell Curve — Sorting by OAL vs. Base-to-Ogive vs. Weight « Daily Bulletin

Thanks guys I'm glad I'm not the only person who enjoys the more esoteric realms of reloading.

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Originally Posted by Cordite

Thank's @Gibo... (O: He heh heh!

While thinking too much I just masking tape "paper" patched thirty 155grain copper electroplated boolits from Gunworks, to go in my No 4 two-groove. Bore slugged at .304 at throat and muzzle alike, grooves .317". Bare bullets measure .307" and are patched to .316". I'll shoot some patched, some bare.

The .307 unpatched ones will likely do just fine, something to hope for as I just managed not to slice my fingers with the craft knife doing those thirty. Even if my job was minimum wage it would not be worth all this fiddling to make cheaper bullets... but it's the fun.

Just realised... I forgot to weigh them all first. Drat!!!

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@Cordite Shit thats a smart idea for pp bullets, I piss around with parallelograms cut from copier paper dampened then wrapped tightly round the bullet so they shrink tight when dry. Fiddly as phuq and a moderatly high fail rate but they do work fine in my 1896 no 1 mk1. Let us know how they go

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Originally Posted by Marty Henry

@Cordite Shit thats a smart idea for pp bullets, I piss around with parallelograms cut from copier paper dampened then wrapped tightly round the bullet so they shrink tight when dry. Fiddly as phuq and a moderatly high fail rate but they do work fine in my 1896 no 1 mk1. Let us know how they go

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@Marty Henry

Thanks but not my idea, I got it from the www of deceit.

Well they didn't go well into the case later in the evening, even with some lube, unless I flared the case mouth "a little bit more than I thought it needed". A single layer of masking tape tears quite well.... )-:

Found some cases (HXP) will only hold the patched .316 bullets after the neck sizing. But other brass (CAC, S&B, PPU) must be made of thicker stuff as after similarly neck sizing them in my .303 Lee Loader they are very happy to grip the unpapered .307 bullets. (I believe I must have measured the bullets wrong btw as they are said to be double sized to .308, both before and after their copper electroplating).

I'll let you know how the shooting went. Worked far away from home this weekend, so no chance till this coming Saturday.

I used to do that and had to flare the case mouths then run them in a neck size die another pain in the arse now I load them into unsized reprimed cases and use a collet neck sizer to hold them. Works very well.