Bullet weight sorting

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.