Will Sorting by Bullet Weight Improve Accuracy

1.3K Views
Last Post 16 July 2022

CBA Member

Wm Cook posted this 03 July 2022

A diversion from the thread "Mold Temperature".

The topic "Mold Temperature" on a different thread gravitated towards a good conversation that kicked around the pro and cons of sorting bullets by weight for the purpose of improved accuracy. John's post suggested a separate thread to discuss sorting versus not sorting. Since I had started the OP on mold temperature I thought it would be OK to start this new one.

(John Alexander wrote) Great idea for another thread. It would be nice if all the posters above who believe minimum bullet weight variation is important for good accuracy would all shoot a similar test. It would be interesting to see the results.

(John Alexander continued) Sort of a cooperative joint experiment. I would be happy to participate if there is any interest. Pretty easy to do even if two ten shot groups of each condition.

There are people with enough credibility on both sides of the "weigh or don't weigh" topic that it might be fun to work with. Bud, Gunarea, John, Aaron and many others have decades of experience chasing small groups.

I'm all in on this. To get started I would like to suggest that someone take the lead. Someone who has a track record conducting trials and writing articles that takes controversial subjects and wrings them out to see if the variable can effect change and take the lead.

Rather than beat around the bush I would like to suggest that Jone takes the point. I recommend that John and another CBA member collaborate on a set of easy to replicate methods that maybe 4 others can follow close enough to make the test valid. Since I started this thread I'd like to be the first to jump in with my "wish list" for Methods.

Use the CBA Group targets. It gives the user a sighter target and a target for score for each of the variables (assuming we follow the suggestion of shooting x number of 10 shot groups. X is defined as he number of variables being tested.
Consider limiting it to one cartridge so if you're talking about +/- .5 grain all results will be close to relative. 30 cal is the most caliber shot in the Nationals.
Outline the expected bullet weight variation in tenths of a grain (drop or lubed) to be tested.
Set a time limit on returns. 30 days is plenty.

If everybody jumped in with their wishes and wants like I just did this could turn into an endless mud wrestling match. That's why I suggested a couple of the respected members of the group draft the methods and they'll be savvy enough to keep it simple.

Volunteers could be sought on line or drafted off line. I don't have a row to hoe in this, I just would like to see a structured test that will give me an edge. I could do it on my own but if we have a small group kick it it may carry more respectability. Sorry for being long winded. Thanks, Bill Cook

Attached Files

41 Comments

Order By: Standard | Newest | Votes

CBA Member

Larry Gibson posted this 03 July 2022

I've been down this path before on this forum. I have posted extensive test results.

Here's the main problem (IMHO) with your discussion and test. "Your rifle does not have to be a bug hole producer. If the rig normally shoots 2" with the best of the loads so be it. You would be competing with yourself."

To actually and realistically show the difference one must properly cast bullets of sufficient quality and one must weight sort them properly. The usually reported "bell curve" weight assortment is not the proper method. The curve must "flat line" at the heavy end for the majority of bullets.

One must use a rifle/scope/bench/rest combination that is accurate enough to tell the difference and one must be able to shoot accurately enough to show the difference. One must also to honestly know the difference between a "called shot" and an actual "flyer". Shooting a milsurp or commercial rifle with issue iron sights won't really show a difference. Shooting at just 50 yards (which many do) won't show the difference. Improperly weight sorting won't show the difference. And using a load with a large SD/ES ratio won't show the difference either.

I shoot a lot of unweighed cast bullets in my rifles when they are used for plinking, casual shooting or "blasting". Almost all are GC'd and I just do a visual cull for defects when putting on the GC, sizing and lubing. I am very happy with the results as most are when doing the same. However, for serious accuracy for CBA competition and HV cast bullet use I weight sort.

Attempting to draw any conclusion based on comparison of okay accurate rifles to those capable of precision accuracy will not solve anything nor answer anything as it is apples to oranges comparison. Not using a rifle/equipment of adequate accuracy capability to show the difference or having the ability to shoot accurately enough to show the difference also will be a problem.

However, individually, such a test will more than likely just tell each tester whether his casting ability, shooting ability and rifle are capable of telling the difference with the load he is using whether weight sorting is beneficial to him.

LMG

Concealment is not cover.........

Attached Files

Liked by

CBA Member

Larry Gibson posted this 05 July 2022

Ross

I mostly just shoot them as "separated by weight" simply because they already are 'separated". I've over 3,000 of them out of the 30x60 XCB at high velocity. Don't know how many but probably around 2,000 out of my M70 match rifle shooting mostly for score on CBA score targets. I run those around 1800 - 1900 fps depending on which powder I'm using. Minus the very small number of the top weight, I generally get the best accuracy score wise with the top weights having not more than a .4 gr weight spread.

Using the top end weights which have the most complete fill out is the key as they are the best balanced.

LMG

CBA score targets shot not too long ago. There was a slight wind (probably 1 to 2 MPH0 coming out of 2 - 3 o'clock. Bottom left is a fouler/sighter target. Top targets i held for the wind.with both being 5 shots. I moved the scope elevation (1/4 moa) between targets. Bottom right is two separate 5 shot strings. The first i held for the wind with the shots centering over the 10 ring. The second I held center X just to see if the wind was drifting/affecting the bullets as much as I was holding for. It was.

In shooting for a 10 shot group with my HV load for this rifle I shot this target. Bottom two shots were sighters. I made elevation/windage correction in the scope then shot 10 for record. I chronographed the 10 shots "for record". Obviously, the care to which I cast the bullets, inspect them and weight sort them pays off.

BTW; IMHO, shooting for score is a lot more difficult than shooting for group.

Concealment is not cover.........

Attached Files

Liked by

CBA Member

Larry Gibson posted this 04 July 2022

Weight sorting for precision [best accuracy] loads

It depends on the weight of the cast bullet to begin with. Most weight sort thinking those bullets that weigh the same or with a +/- will shoot the best. I've learned that while that method of selection will give better accuracy it will not give "the best". As I weigh each bullet, I visually inspect the bullets first. Any visual defect, no matter how small, is cause for rejection. I then weight sort to eliminate those very light bullets that passed the visual inspection but obviously have a void inside. I then put the bullets into small plastic bowls of .1 gr increments.

I'll explain with 7mm to 32 caliber bullets of 150 to 220 gr as an example. Many who weight sort will kind of "graph" the bullets out by lining them up in tenth grain increments that are consecutively numbered and straight across the bottom. What you end up with is a "bell curve" shape of bullets. The curve starts out curving up, peaks out and then curves back down almost the same as it went up. The majority of the bullets in the curve will have a 1 to 1.5 grain difference in weight. There will be some that are much lighter and a few heavier. That is what you get with "good" cast bullets.

Using a quality alloy that will cast excellent bullets is also paramount. This is why straight linotype and #2 alloy are most often used. They give excellent and uniform fill out, consistency of weight with fewer defects. Some batches of COWWs will also if the antimony and tin percentages are sufficient and balanced. Alloys in these smaller caliber bullets that give a lot of shrinkage will never cast "excellent" bullets no matter how good they look. The reason is we cannot control the shrinkage and where it occurs on each bullet. Slight shrinkages that are in different places on the bullet are undetectable by visual or even precise measurement and they mean a slightly unbalanced bullet. Might not seem like much but at higher RPM and/or at longer ranges of 200 yards and beyond it is readily detectable on target by enlarged groups and poorer accuracy. Complete fill out in the mould and minimal shrinkage is needed for a quality cast bullet that will give the best accuracy.

Weight sorting the visual inspection passed bullets with "excellent cast" bullets gives a weight sorted curve that rises sharply and then levels off with several weights (three or four of .1 grain increment) having about the same number of bullets. The curve then falls sharply to just a few heavier bullets. There is no downward "curve".

When I got the 4 cavity NOE 30 XCB mould I ran this test with Lyman #2 alloy;

I cast 531 bullets

1.9% were rejected for visual defects

8.6% weighed less than 157.7 gr (some as much as 2 gr less that obviously had internal voids I could not detect through visual inspection)

3% weighed 157.8 gr

4.5% weighed 157.9 gr

5.9% weighed 158 gr

18.7% weighed 158.1 gr

19.3% weighed 158.2 gr

21.6% weighed 158.3 gr

14.7% weighed 158.4 gr

1.8% weighed 158.5 gr.

I then loaded 10 shots of each increment (157.8 gr to 158.5 gr) to test at 300 yards.

Test rifle was my 30x60 XCB. The NOE bullets weight 164 gr +/- when fully dressed and were loaded over 53 gr of AA4350 which runs 2900+ fps out of that rifle. The incremental test loads were fired consecutive by weight with the barrel cooled, cleaned and then fouled with 2 fouling shots prior to the next increment test. The results were then graphed out for a simple visual comparison.

We see the lighter weight 157.8 and 157.9 gr bullets were not as accurate. The lighter weight bullets giving indication to probable incomplete and inconsistent fill out and/or shrinkage or that they have small void(s) in them. The "heavy" end of the bullets (158.0 through 158.5 gr) gave consistent accuracy (precision) at very close to moa at 300 yards. I have run this test several times and with cast bullets in the 150 - 180 gr weight range I select the heavy end of the weight sorted bullets +/- .2 to .25 gr. With this weight range I use the 157.8 and 157.9 gr bullets for foulers and the 158.0158.1 bullets for sighters. The 158.2 through 158.5 are then used in matches and other tests where precision is measured. For the best accuracy at this level of high velocity the top half (158.3 to 158.5 gr) of those selected bullets almost always give the best results, particularly at 200 and 300 yards.

With other weight ranges I like wise run a similar weight sort test and now select the heavy end of the match selected weight sorted bullets for accuracy/precision use.

LMG

Concealment is not cover.........

Attached Files

Liked by

CBA Member

Larry Gibson posted this 04 July 2022

Weight Sort 30 XCB Cast Bullets

Ten years ago I thought I was casting pretty good bullets, excellent in fact. However. the more I got into shooting cast bullets at HV I found while I was casting good, excellent bullets I too hit the accuracy wall that many allude to of 1 1/2 moa +/-. I also found that when those cast bullets were pushed to really HV (2500 - 3000+ fps) they did not do as well as expected. Back then I was weight sorting as we've all been told to. If you line them out by weight you get the so called "bell curve". In proving insanity, I, like you and everyone else, then did the same testing of each .1 gr testing over and over again expecting different results.....we all got the same results; accuracy was not really improved via that method no matter how many times we ran the test. If you are asking us now to run the same test and think the results will be different? It wouldn't happen, as the results will still be the same.

Proper weight sorting

Let's assume we have a mould that will cast perfectly even bullets in all dimensions. Not an assumption but fact is that mould has a finite capacity for any alloy. Thus, if we cast with a good alloy giving the best fillout then only those that weigh the heaviest will have filled the mould out as completely as possible. Any bullets with less weight are then not dimensionally the same. We may not be able to measure other than weighing that difference, but the difference is there in lighter weight bullets none the less. Understanding the difference in weight (mass) is there but it is not predictable and most often not perceptible except by weight sorting.

Never too old to learn.....

I recently cast 542 NOE 30 XCB bullets of #2 alloy. I have just completed weight sorting them. In the next post I will show the graphed results of the weight sort which should aptly demonstrate what I'm saying. Have to copy, download, etc. so it will be an hour or so.

Here is the results of the weight sort. 542 bullets were cast of Lyman #2 alloy and WQ'd. They were then aged about 12 days before I got around to weight sorting. Here is my set up for weight sorting. I visually inspect each bullet for any defect. If any is found that bullet is rejected to be melted and recast at a later casting session. Those that pass my anal visual inspection then have any remnant of the sprue cut off. That is done on the lead block with a sharp blade on the pocket knife. The bullet is then weighed on the Redding balance beam scale. While waiting for the beam to settle I then visually examine and sprue cut another bullet. With the magnifier in front of the scale I can readily and accurately see what the weighed bullets exact weight is. The bullet is then placed in a bin for that weight.

Of the 542 bullets weighed 22 were rejected for a visual defect or because they weighed less than 156.9 gr which means the weighed ones had passed the visual inspection but still weighed way lite. The remaining 520 XCBs were weight sorted into separate bins of .1 gr increment from 156.9 gr to 158.0 gr......a 1.1 gr spread. We don't know where in or on the bullet that difference in weight is missing from. The missing weight is what creates the imbalance. I suspect voids in the alloy are not the problem, but rather other aspects are which I have previously discussed.

The weight sorting is showing us the 113 bullets of 157.7 gr, the 124 bullets of 157.8 gr and the 119 bullets (I'll put the 158.0 gr bullets in with those) of 159.9 gr weight has the highest weight/mass of alloy in them. Since the curve dropped off suddenly we see those weight bullets are the most consistent and the best the mould will produce with that alloy. Those 356 weight selected bullets will be used for best accuracy.

The 157.6 gr bullets will be used as fouler/sighters as I expect they will give very good accuracy also given only a .2 gr +/- difference in weight.

Had we lumped all the visually selected bullets into one group 70% would have been with the excellent bullets, another 15% would have been with the fouler/sighter bullets and the remaining 15% would have been with bullets having a weight/mass difference of 1.1 gr. Now, had I done that I probably would have got nice 1 1/2 moa groups with 7 +/- shots going into moa or less and 2 -3 +/- shots going out of the group in the 1 1/2 moa +/-. How many of you shoot groups like that with bullets only visually sorted?

It is with such weight sorted selected bullets (the 157.7 to 157.9 gr bullets) that I am able to hold moa accuracy to 300 yards and beyond with a 2900+ fps velocity.

That is how I weight sort the bullets I use for precision shooting and why it makes a difference.

LMG

Concealment is not cover.........

Attached Files

Liked by

CBA Member

RicinYakima posted this 03 July 2022

"However, individually, such a test will more than likely just tell each tester whether his casting ability, shooting ability and rifle are capable of telling the difference with the load he is using whether weight sorting is beneficial to him."

That is my position also, Larry.

Attached Files

Liked by

CBA Member

Wm Cook posted this 03 July 2022

That's a very sobering thought. In jacketed br there are few called fliers. If a group opens up from the low .2's to the mid or high .2's its either the user, the load or the wind. With enough time on a stool shooting custom rigs the user rarely makes self inflicted mistakes. By far, wind is the single greatest obstacle. I got out shot all the time but it wasn't because of equipment, load development or bench equipment/technique. It was the wind. I'm carrying too many preconceived attributes into cast accuracy. I can't even fathom shooting for accuracy without a 36 to 50 powder scope. And to be perfectly clear, 99 of 100 military rifle shooters would kick my butt. I appreciate the reality adjustment and hope I didn't offend anyone. Bill.

Attached Files

Liked by

CBA Board

Paul Pollard posted this 06 July 2022

These targets were shot with weight-segregated bullets. I'm not sure what caused the variation on diameters. The batch was separated into 0.10 grain. The lightest were 76.60 - 76.78 grains. They were .2460 diameter. Next was 76.80 - 76.88 and were .2463 diameter. Next were 76.90 - 76.98 grains and were .2465 diameter. Next were 77.00 - 77.08 and were .2468 diameter. Heaviest were 77.10 - 77.18 and were .2470 diameter. I didn't shoot all the separated batches and don't remember why. The limited test indicates there may be something to heaviest of the batch shooting slightly better. These are 100 yard targets. The bullet hardness was 22 -23 BHN and velocity was around 2100 fps.

I still have some of these bullets left, so may try this again.

Heavy Targets Lightest

Attached Files

Liked by

CBA Member

Larry Gibson posted this 07 July 2022

John

No offense meant in my last post.

There was a question mark in parenthesis regarding the 1 moa discussion because I wasn't sure it was you who posed the question or not.

A couple corrections if you don't mind;

Apparently, you're assuming (?) I'm only posting results from HV tests? Such is not the case. In the "shooting behind the graph", Yes they were HV loads. There were 6 successive ten shot groups fired at 300 yards with a 2900 fps load that maintained 1 moa accuracy. Those were from the heavy end of the weight sortment. The 2 lighter weight bullet groups did not shoot as accurately. That example was not to show anything for CBA competition but to show the difference in weight sortment accuracy/precision results.

The next post showed 4 different groups (5 shot) on CBA score targets shot at 100 yards. The reason for 5 shots was because in CBA score matches only one shot is fired per bull for score on the 5 score bulls per target. Those were not HV but at 1700 fps were well within the spectrum of posted CBA velocities for the 308W. The groups were under 1 moa [actually .970, .670, .1.170 and .590] but since I was not actually shooting for group but for score one might look at both score and group?

I also posted a benchrest target for group. There were 2 sighter/foulers then a 10 shot group at 100 yards. The 10 shot group measured .870. Again, that 308W load was at 1700 fps using the selected weight sorted bullets. That certainly falls under 'the usual CBA velocities and under 200 yards" criteria.

However, the real point to my last post is apparently lost in the fine print. I've been on this forum and the other one for many years now. I've engaged in trying to further our knowledge of cast bullet shooting across the spectrum of obtainable velocities and had many discussions on various topics. I've found that when someone can't agree whether right wrong or indifferent, the usual response is "we need more testing". Then when further testing is done and they still can't see the validity of the results they say something like "well, you should have tested this way" or something similar. Seldom will the naysayers provide their own tests to disprove what has been shown.

"I have shot lots of groups of light vs. heavy over the years at about the same group size as yours and found that the light bullets shoot just the same as heavy, so naturally I am curious why we get different answers."

If you're shooting "light vs heavy" then you have weight sorted them, correct? You are comparing the group size of one weight to the other, correct? Did you note any difference in the center of the groups which might indicate a shift in zero based on the lighter or heavier bullets? Such a shift is not relevant to groups size but it sure can be when shooting CBA score matches.

You've posted no data on the variances so I may be going out on a limb here, but my assumption is you cast bullets of excellent consistency. If so, then the groups sizes probably won't be that much different as most of your bullets probably would fall into the top "level" end of the weight spectrum category. As we see from my own weight sot/testing it is not just the very heaviest bullets that shoot well, particularly at 100/200 yards but the bullets that fall into the "level" portion of the weight sortment. With my 30 XCB bullets I find that "level" to have a 4 -6 tenth grain (.0035% +/-) variance.

I also recall some discussions as to why we get "outliers" or non-called flyers that can open the group, only if a little. unless the bullets have been weight sorted perhaps those just might be a bit lighter weight bullet even though they passed visual inspection?

One last question; when you weight sorted, did you get a bell curve or did you get a flat line at the top end weights as I've discussed?

LMG

Concealment is not cover.........

Attached Files

Liked by

CBA Member

Wm Cook posted this 03 July 2022

It's possible that those that hold opinions regarding the value of sorting cast bullets by weight will or will not improve accuracy has been away from the forum. Or maybe some would prefer to keep talking the talk instead of walking the walk. The reason for the latter could be for any number of reasons but I'm certain that no amount of communication on a forum will sway folks away from either position.

What was proposed is not difficult. Someone write up a set of methods. I recommend the participants use CBA groups targets. We could use five targets with each having one bull for sighters/zero and one for record. And I'm still pushing for similar calibers so the +/- weight variation is somewhat relative.

Allow one target to zero, shoot your pet load for record and to warm up. The final four targets are each shot with 10 shot groups plus whatever you need on the sighter. Sorting to the degree the methods allow two groups will be shot using weight sorted to .x grains and two groups will be shot sorted to .y grains.

Your rifle does not have to be a bug hole producer. If the rig normally shoots 2" with the best of the loads so be it. You would be competing with yourself.

The only requirement is that the participants must be capable of using match grade casting, reloading and bench equipment and match grade casting, reloading and bench practices. I hope I didn't hurt anyone's feelings and promise to drop the subject after this. Thanks, Bill C.

Attached Files

Liked by

CBA Member

porthos posted this 03 July 2022

it might be eaiser to tune your casting technique to get the weights closer. i cast with a ladle and the weight variation is less that 0.2 (2 tenths of 1 grain). i have a NOE 3 cavity mold for 303 that will hold that variation.

Attached Files

Liked by

CBA Member

Shopdog posted this 03 July 2022

I'm with porthos above....

Although bttm pouring,it is very rewarding being able to cast to extremely tight tolerances. To the point that,not only weighing becoming a waste of time but,it does move accuracy in a positive direction. The argument of shooting "culls" or anything other than preemo bullets,is also a waste of discussion. Don't cast poor bullets.

Attached Files

Liked by

CBA Member

Bud Hyett posted this 03 July 2022

One thought in all this testing; how do we test the shooter on the day the test is being performed? This question was asked me many years ago at Windhill when I was complaining that the rifle was not repeating groups from the previous week. Ed Doonan told me when he started serious load development, he shot his match .22 LR for a few groups to be sure the anomaly was not him.

Since then, my first testing is with a BSA Martini International with a known lot of .22 LR match ammunition for that rifle. If the groups are repeating from previous days, then I know I am ready to test. This means taking another rifle to the range and more targets. But I usually spend an entire day at the range and this is not a bother.

Farm boy from Illinois, living in the magical Pacific Northwest

Attached Files

Liked by

CBA Member

Wm Cook posted this 03 July 2022

If there’s lead in the story maybe you should start a thread. One of the most fun cast rifle I owned was an old Marlin 336 lever gun in 35 Rem. Had to go to receiver sights. Eyes are too old to connect the rear sight and the front post. Didn’t need to do a lot of sorting bullet weight for that one . Nearing 1800 fps with your Henry might be just a tad too quick to keep leading away.

Attached Files

Liked by

CBA Member

Wm Cook posted this 04 July 2022

Great detail Larry, thanks. You've given a lot of your time to helping others. I and many more like me appreciate your work. My hats off to your experience and work ethic.

Attached Files

Liked by

CBA Member

Larry Gibson posted this 06 July 2022

John

"I hope you will follow your own suggestion and use the left over bullets to go back and do it again. I also hope Larry does the same. Although it is harmless fun to look at single groups of different weight bullets. We all know (I think) that it doesn't mean a lot until the number of shots fired for each weight is far more than ten shots each."

The graph in my first post is made from the results of 8 ten shot groups at 300 yards. That's 80 shots for 8 different ten shot groups at 300 yards. Then I followed it with further testing of of weight sorted bullets in the .308W, the 30-06 and in the 7.62x54R (of which I've won numerous military rifle matches with down here with the CBA guys over in Phoenix). I've also posted 3 separate 10 shot groups at 600 yards which averaged less than 1 1/2 moa (one group of 11 shots was less than moa). None of those were "lucky" and the accuracy shown has been consistent.

Just how much testing is actually needed? It is obvious from your previous discussion you think weight sorting isn't beneficial and perhaps it isn't to you. I believe you also pondered the question before whether or not 1 moa is about the best we will do with cast bullets(?). I posted 4 consecutive 5 shot groups under 1 moa. the graph mentioned has 6 consecutive 10 shot groups at 300 yards of moa accuracy.

Again, you ask for "more testing"? You know the definition of insanity? "Doing the same thing over and over yet expecting different results. I've done the same thing over and over again [as in "testing" weight sorted vs non wight sorted cast bullets] and I do expect the same results. Apparently, I'm must not be insane......

LMG

Concealment is not cover.........

Attached Files

Liked by

CBA Member

Larry Gibson posted this 08 July 2022

Okay, I probably didn't explain sufficiently enough about the groups on the CBA score targets. Let me clarify. I posted;

"CBA score targets shot not too long ago. There was a slight wind (probably 1 to 2 MPH0 coming out of 2 - 3 o'clock. Bottom left is a fouler/sighter target. Top targets i held for the wind.with both being 5 shots. I moved the scope elevation (1/4 moa) between targets. Bottom right is two separate 5 shot strings. The first i held for the wind with the shots centering over the 10 ring. The second I held center X just to see if the wind was drifting/affecting the bullets as much as I was holding for. It was."

The rifle used was my M70 match rifle which started life as a factory heavy varminter. It is still in factory configuration with the factory 1-2" twist Winchester barrel of 26" length. It wears a Leupold 6.5x20 target scope with 1/4 moa adjustment. The NOE 30 XCBs were cast of #2 alloy and WQ'd out of the mould. They were weight sorted as mentioned in a previous post. They drop at .3105. The bullets were GC'd, then lubed in a .311 H&I die with 2500+ or Javelina. The bullets were loaded in match prepped LC 92 match prepped cases which had the flash holes drilled out. Primers were WLRs and 16.5 gr of Alliant 2400 was used. No filler was used but I did use my version of loading I call the "SAAMI Twist" positioning the powder uniformly when loading the cartridge into the rifle

The bottom left target is the fouler/sighter target. This rifle most often puts the first 2 shots out of a cold clean barrel a bit low right. That is also evidenced on the CBA target used for group. However, depending on the powder being used the sighter/foulers can also hit elsewhere out of the group. After the two sighter/foulers the rifle shoots to group. There was little to no wind. The first shot is at 40 on the 8 ring. The next 2 shots are together on at 40 on the 9 ring. I adjusted the elevation up 3 clicks and put the next 2 shots on the 9 ring at 2 o'clock. I then adjusted the elevation down 2 clicks and windage left 1 click. There are 6 shots on that target.

I then shot 5 shots on the top left target. There was still no wind so I aimed at the "X" dot for each shot. That group measured .970, was centered for windage but still low. I adjusted the elevation up 1 click.

Moving to the top right target there was still no wind so, again, I aimed at the "X" dot and shot that 5 shot group. That group measured .670 and scored 100.

Moving to the bottom right target the first group of 5 shots which are the 2 Xs, the 10s at 12 and 20 and the 9 at 50. I called that 9 shot but still counted it in that group. That group measured 1.170.

A cease fire was called for shooters to check targets or hang new ones. When the line went hot again a 1 -2 mph steady wind had begun coming out of 2 - 3 o'clock. I had 5 rounds left so I decided to hold on the "X" dot on the lower right target (since I had blown that group) to see just how much that wind would affect the POI. Those 5 shots are the cluster at 3 o'clock between the 9 and 10 ring. That group measured .590. The wind had moved the POI 1/4 to 1/2 moa left.

Thus, there are 4 separate 5 shot groups on those 3 targets.

"When weigh sorting for tests I did not get a pretty bell shaped curve but an asymmetrical shape with a "tail" on the light end an abrupt drop off similar to what you found on the heavy end."

As I suspected, you are indeed casting excellent bullets. The problem is you admit to being "too pig headed" because you've already determined, for yourself, that weight sorting is a waste of time. I do not find it a waste of time. The reason being I find with my cast technique for the 30 XCB bullets, when casting 500 - 600 in a session, I have 13 - 15% rejection rate based on visual and weight sorting. Eliminating those lighter weight bullets by weight sorting has also eliminated the 1 or 2 shots out of 10 that may sneak out of the group or out into the 9 or 8 ring even though the shot was called good. Now, if I have a flyer out of the group or the 10 ring I know the reason why.....me. Knowing that is beneficial to me and why I weight sort.

The OP, Wm Cook, asked basically, can weight sorting improve accuracy. As I stated in my first response to him; "However, individually, such a test will more than likely just tell each tester whether his casting ability, shooting ability and rifle are capable of telling the difference with the load he is using whether weight sorting is beneficial to him." And so, it is and I'm not trying to convince you that you must weight sort. All I've done is post the how I weight sort, the why I weight sort and have given the results of weight sorting in my match loads.

LMG

Concealment is not cover.........

Attached Files

Liked by

CBA Member

David R. posted this 03 July 2022

Just my thoughts. I recently started weighing my bullets and culling them. I haven't gotten very far with this yet. However I recently went to the range to test some .357 magnum loads in my Henry. I was shooting off a bench and using a chronograph. Ten shots were within 5 fps with three duplicates. I'm used to seeing a tight velocity spread with black powder but not so close with smokeless. I was impressed. Unfortunately I was having trouble with the sight on the rifle and stopped the test because I couldn't see well enough to aim precisely and it was clear that I had the wrong front blade on the rifle. I intend to take this up again when I have an opportunity. For my own information I'm thinking that I will load some culls (no visual flaws, just outside of weight parameters) and do my own comparison. Who knows....may not be a nickel's worth of difference, but I will have answered the question for myself.

I only recently learned that temperature effects weight. I have started monitoring my temperature more closely and have far fewer culls as a result. Just my 2¢ worth for today.

Attached Files

CBA Member

Wm Cook posted this 03 July 2022

If you’re after small bullet weight deviation I think it’s something that you have to keep working as it. Even those that don’t sort for weight have their methods wired in to do the same thing the same way every time. I’m starting to learn that cadence / temperature is kind of important. As an off topic question I have to ask what powder you were using David? 357 Henry sounds like a whole bunch of fun. Bill.

Attached Files

CBA Board

John Alexander posted this 03 July 2022

I commend Bill on suggesting a joint testing effort and joint discussion. Since Bill outed me as the guy who suggested trying it I think I should at least comment. My suggestion was probably not a realistic suggestion. Not because of all the reasons above which can be easily overcome by anybody who really wants to find out, but because there just isn't much interest in finding out when you already know you know the answer and are happy in your belief.

Porthos and Shopdog say just cast good bullets. Everybody agrees. Nobody is advocating using bullets that enlarge the group, But how do we know how much variation in weight will enlarge the group? If we are casting excellent bullets, do we still need to sort by weight?

By the time most cb shooters are averaging five shot groups under 1 moa they have learned to cast excellent bullets that vary no more than two to five-tenth of a percent. BUT THEN most sort by weight down to one-tenth of a percent variation (0.2 grain variation in a 200 grain bullet.) Most actually sort to 0.1 grain and some to 0.05 grain. The question is -- does this sorting shrink groups below what they would have been if left with 0.5 grains of variation?

Running the simple test Bill suggested would answer that question but with a couple of exceptions all the shooters I have discussed this with have NOT tested to find out. They just sort.

100 bullets used in the test and one day weighing, loading and shooting would probably tell, to a high degree of confidence, whether sorting improved groups but why bother if you already know that sorting improves groups no matter how good the bullets were without sorting. I don't understand this mind set, but that's the way it is.

John

Attached Files

CBA Member

David R. posted this 03 July 2022

Accurate #9 was the particular powder. It was with a 170 grain SWC. Velocity was in the 1,790s. I had lead fouling afterwards and that bullet didn't feed very smoothly. I won't be using that combination again.

Regarding the "fun" of the Henry, I have to confess that I haven't had much fun yet. I hope that it will get better. I considered posting my saga, but it's far from over and I'm not sure if folks are interested in my silly story.

Will Sorting by Bullet Weight Improve Accuracy

Categories

Search

Popular Tags

This Weeks High Earners

Hot Topics