Bullet Sorting Methods

[suasponte]

Fclass, never shot 1000yd bench rest. I have sorted, weighed, meplat, tipped, and never noticed enough to warrant doing it. I shoot 1000yd every weekend. Neck tension and powder charge weights is where I noticed the gain in vertical dispersion. How are you sorting, base to ojive?

 

[retired]

right, i'd ask when was the last time you shot long range and won ?
and i am talking br not mil giant 2 moa 10 rings

You'll gain more learning shooting in the wind then sorting (QUALITY bullets) any day.
Terry

 

[Bart B.]

Maybe in F-Class but not BR. BR is all about groups. Wind isn't near the factor. You sometimes lose by less then .010. Matt

I don't think there's any significant difference in accuracy across benchrest and prone rifles. The best of them properly tested put all shots for the life of the barrel inside 5 to 6 inches at 1000 yards.

The holding (point of aim) area on target for one is less than a few hundredths MOA , a few to several tenths MOA for the other. One has very repeatable bore axis movement during barrel time, the other has several tenths MOA spread.

A group match lost by .010 inch is the same as a bullseye match lost by .010 inch. Both events use gauges to resolve close shot holes to .001 inch or less.

Bullseye matches are all about hand held rifles' groups centered in the scoring rings. They reveal all the shooter's marksmanship skills.

 

[suasponte]

right, i'd ask when was the last time you shot long range and won ?
and i am talking br not mil giant 2 moa 10 rings

I just posted I don't shoot br so How could I have won If I don't shoot Long range BR?

 

[dkhunt14]

Fclass, never shot 1000yd bench rest. I have sorted, weighed, meplat, tipped, and never noticed enough to warrant doing it. I shoot 1000yd every weekend. Neck tension and powder charge weights is where I noticed the gain in vertical dispersion. How are you sorting, base to ojive?

I sort just the bearing surface. Matt

 

[suasponte]

I sort just the bearing surface. Matt

Thanks for your response.

 

[Linko]

I loved my Bob Green. But I am selling my 6mm Bob Green comparator since I no longer shoot 6mm.

 

[barefooter56]

Just finished going through my first two 500ct boxes of Berger 105g Hybrids, only to find my just purchased two 500ct boxes, lot C155 are .034" shorter OAL and .037" shorter BTO. Appears that most of this is a change in the boat tail area. Now it's back to load development all over again......sigh.

Try this: do not adjust the bullet seating stem from where it was on your previous lot. Seat a bullet from the new lot and measure the CBTO. It should be the same or very close to the CBTO of the previous lot. If it is. Drop the load a grain and work it back up slowly till you get back on your velocity accuracy node. If they don't seat anyway near what you had before. Check and make sure the tip of the bullet is not bottoming out in the seating stem cavity. If you don't have a VLD bullet seating stem in your die . Get one.
I took 3 separate lots of our 6.5 130VLD Target bullets. Age between lots was about 2 years. Set up my seating die to my CBTO bullet seating accuracy depth off the lands on one of the lots. Then seated the other two lots with no adjustment to the stem. Other two lots were + or - .0005 from the first. Bullet base to ogive of all three lots: 0.6200 , 0.6750, 0.6525. Just for grins I loaded them all with the same powder charge and they shot into about a .250 group at 100 yards . Then ran them over the chronograph two had SDs of 11 . One was 4.3. So some powder charge "tweaking" is in order. Then retesting. When it gets warmer and I can get out to the range that is the next thing that gets done.

 

[B_Thomas]

Try this: do not adjust the bullet seating stem from where it was on your previous lot. Seat a bullet from the new lot and measure the CBTO. It should be the same or very close to the CBTO of the previous lot. If it is. Drop the load a grain and work it back up slowly till you get back on your velocity accuracy node. If they don't seat anyway near what you had before. Check and make sure the tip of the bullet is not bottoming out in the seating stem cavity. If you don't have a VLD bullet seating stem in your die . Get one.
I took 3 separate lots of our 6.5 130VLD Target bullets. Age between lots was about 2 years. Set up my seating die to my CBTO bullet seating accuracy depth off the lands on one of the lots. Then seated the other two lots with no adjustment to the stem. Other two lots were + or - .0005 from the first. Bullet base to ogive of all three lots: 0.6200 , 0.6750, 0.6525. Just for grins I loaded them all with the same powder charge and they shot into about a .250 group at 100 yards . Then ran them over the chronograph two had SDs of 11 . One was 4.3. So some powder charge "tweaking" is in order. Then retesting. When it gets warmer and I can get out to the range that is the next thing that gets done.

Thanks for the reply.

It does appear the seating stem setting does give same CBTO. So, the shorter length is in the bearing surface length and BT. I do like the fact that the short bullet moves the bottom of the bearing surface/boat tail junction up father in the short neck of the BRX case.

With the longer Hybrids my upper node centered at 32.9-33.0 of Varget (2970-3020fps - BRX). With the new shorter hybrid, 33.0 falls apart. 32.8 still works but not as well. Probably spot on by dropping powder charge and working back up to around 2970 fps.

Weighing 10 of each, yielded a population overlap, so weight is pretty much the same.......

 

[David Christian]

Larry W. was bragging about inventing the 3 point contact and I wondered why all of the reloaders got all giggly. And then I figured it out; none of them ever milked a cow on a four legged stool, I prefer the full circle contact.

F. Guffey

Why are you so opinionated? I recently started using this forum and have read many of your posts which tend to be antagonistic. How about having a bit more grace and spreading positive education to those of us whom are trying to learn verus just being right!

 

[DRNewcomb]

Focused oscillating magnetic field sensor using eddy current measurements

An X-RAY of the bullet in short, and yes ,i own one

It's not a Juenke

This is one of only two non-destructive ways I know of to get a handle on jacket concentricity, which other than voids, is the single biggest contributor to bullet accuracy. (The other involves spinning the bullet at tremendous speeds.) Most people ignore this because either they can understand the concept or the device is beyond their ability or budget. You can have a whole run of bullets which all weight within a gnat's patoutee of each other and are exactly the same weight but won't perform beyond 100 yards if the jackets are not concentric.

 

[Bart B.]

This is one of only two non-destructive ways I know of to get a handle on jacket concentricity, which other than voids, is the single biggest contributor to bullet accuracy. (The other involves spinning the bullet at tremendous speeds.)

Sierra Bullets' tool and die shop made a collet to hold bullets then chucked it in a Dremel Moto Tool. Connected an amp meter in line with its power cord. Bullets were spun 30,000 rpm

Those that were well balanced drew the least current. As unbalance increased, so did current to spin at speed as bearings had more radial load, A few were unbalanced enough to fly out of the collet.

Perfectly balanced ones shot several 10 shot groups at 600 yards from 1.5" down to .7". Then put 40 inside 1.92".

Lapua 30 caliber D46 185-gr. FMJRB match bullets were used in 308 Win cases.

 

[Bart B.]

Once again, calling the BS Flag to these claims.
Put up the actual results and full particulars to these claims.

Contact Middleton Tompkins about that. He did it back in 1971. He knows the actual results and full particulars. I only know the general results and basic particulars based on my conversations with him.

One group at about .8 inch was pictured in a Lapua bullets ad in a late 1971 issue of American Rifleman magazine

 

[Bart B.]

Your the one that repeatedly posts and claim these stats, so you contact who ever all, and put the actual results and particulars up. Do that and I will reverse the BS Flag alerts.

I can't speak to 1971, or any further back then the past 18 years or so, but I have never seen actual results that would come close to what you claim. You present it like it is common knowledge and a easily feat, so I say prove it or I will continue to put up the BS Flag alerts, which is how I see your claims.

Whatever makes you feel good.

BS flags often indicate ignorance. Everything that happens is not always detailed by their creators in worldwide print with words and pictures for all to see and learn from.

 

[Bart B.]

Yawn...... ZZZZZZZZZzzzzzzzzzzzzzzzzz

 

[Titan]

C

Unsubstantiated claims and 2nd hand information to result data from long ago, can more then often indicate ignorance and/or bullshit. Fiction in test results is a smear, nothing to learn from, and low in moral.

Chapter 9 of Harold Vaughn's Rifle Accuracy Facts covers the topic of bullet imbalance, he presents a model and experimental data as well as two methods of measuring center of gravity offset(torsional balance for a static balance and an air bearing to spin balance the bullet). It is a interesting read while a collet and a Dremel are not used it does explore the effect of imbalance and dispersion on target. I would be interested if anyone has explored other methods of measuring and sorting bullets by center of gravity offset or has any other methods to sort by dynamic balance.

 

[BOB LEE SWAGGER]

 

[Regnar]

People calling others know it alls being know it alls. I love the well i dont know about it so it cant be crowd just as much. but when you combine the two that is just some kind of special.

 

[retired]

i KNOW who tom and dmoran are, bartb i do not know.
i am leaning to the tom side.
now if someone came back and says sierra tested lapua bullets, took the best and had a known top shooter shoot them in their tunnel....not really match conditions. Mid was one of the best.

People calling others know it alls being know it alls. I love the well i dont know about it so it cant be crowd just as much. but when you combine the two that is just some kind of special.

 

[Dusty Stevens]

People calling others know it alls being know it alls. I love the well i dont know about it so it cant be crowd just as much. but when you combine the two that is just some kind of special.

All he wants to see is actual data. When claims are just wildly thrown out with no way to prove it that goes very hard against modern recorded results just for the sake of conversation makes this place a fantasy land where who knows what color the sky is when they read to try to learn. We are guardians of knowledge not coffee shop patrons and when claims go unchecked then internet searches reveal this place to be a romper room. Imagine you do a search for actual results of a particular thing, no matter what it is- your search reveals several sources of data, pics, etc but one website says their results are better youll just have to trust us. That website is quickly discredited.