Newbie Load Development Question - How many rounds and how many grain increments?

[CleanShot]

OCW seems like a pretty easy to follow process. I've gotten everything from "I always full resize" to "only neck size" but the latter makes the most sense to me so that's what I'm going to start with. I think I'm going to start as soon as I can get home from work before 9pm... hopefully next week that will happen.

 

[Bart B]

Most benchrest people switched to full length sizing some years ago.

Match rifle competitors have full length sized fired cases since the 1950's when Sierra Bullets proved it to be the best way. Sierra still tests all their rifle bullets in full length sized cases.

Full length dies keep the case body aligned with their necks when sizing. Don't happen with neck only dies. Full length sized bottleneck cases center bullets better in chambers.

 

[CleanShot]

Most benchrest people switched to full length sizing some years ago.

Match rifle competitors have full length sized fired cases since the 1950's when Sierra Bullets proved it to be the best way. Sierra still tests all their rifle bullets in full length sized cases.

Full length dies keep the case body aligned with their necks when sizing. Don't happen with neck only dies. Full length sized bottleneck cases center bullets better in chambers.

Interesting. This entire process is so complex. I keep feeling like I'm making wrong decisions for purchases and everyone has differing opinions. I've been hearing from a few people that full length resizing is now the preferred method. I sometimes feel like this stuff is a bit of science mixed with a bit of voodoo and superstition. At this point I just want to get started and stop overthinking it.

 

[Rich Coyle]

Many years ago I tested this subject. The writing may not be professional level, but you can still glean the results.

Necking and full contact.


The objective of these groups is to compare full length resized .223 Remington cases to cases which were neck sized only. On the full length resizes cases, I pushed the shoulders back about .001" so they would fit the chamber with absolutely no bolt closing resistance. A Stoney Point over all length gauge help with this task. I sized the necks in a Hornady .224 neck sizing die about .100"; which was plenty to hold a 52 grain JLK bullet since it was seated only .080". All full length cases were resized utilizing the Hornady New Dimension Custom Grade dies. Records for this load indicated the moly coated JLK 52 bullets should touch the rifling for best accuracy in this rifle. The barrel cooled quickly between groups because the temperature was 30 degrees when I started shooting and edged up to 35 degrees by the conclusion.


Four different powders were utilized during the test. To keep even the velocity as close to the same as possible, I guessed the following loads would produce about 3,600 feet per second from the twenty-six inch blue Savage: H 322 needed 26.7 grains, H 335 needed 29.2 grains, AA 2230 needed 27.5 grains. BL-C(2) had to be poured very slowly to get 30.7 grains into the case.


In the event of fliers from this out of the box Savage rifle, the best four shots out of five are also included. The rifle was cleaned and three fowlers fired prior to the testing.


H 322 charged full length resized cases produced a velocity of 3,548 fps. The group measured .579" with 4 @ .415". The neck sized cases generated 3,586 fps and a group of .844" with 4 @ .486". The neck sized cases displayed a velocity increase of 38 fps over the full length sized cases. It was the only one of the four that showed the full length cases producing a smaller group than the necked cases.


H 335 powered full length cases produced 3,558 fps and a flyer group of .784" with 4 @ .379". The neck sized speed was 3,607 fps and the group was .527" with 4 @ .473". This time the neck sized cases exceeded the full length cases by 49 fps.



AA 2230 loaded full length cases pushed the 52s to 3,531 fps, and the group was .604" with 4 @ .337". The neck sized cases did 3,580 fps and made a group of .445" with 4 @ .250". Again the velocity for the neck sized cases was higher at 49 fps than the full length cases.


BL-C(2) full lengthers flew down range at 3,532 fps and made a group of .671" with 4 @ .406". The necked sized load dashed away at 3,574 fps making a group of .491" with 4 @ .394". The velocity advantage for the neck sized cases was 42 fps. The average for the full lengthers is .6595". On the other hand the neckers averaged .5767" for a difference of .0828".

 

[4xforfun]

morning yes I have a rcbs 1500. yes u can measure .005. instead of being so pessimistic

add some advice to help this newbie progress his skills and gain confidence to progress

his needed reloading skills. r u could keep belittling me and show ur incompetence.

I never belitteled you!! I am simply asking that if you were working up a load...lets say a 7mm Rem Magnum with H1000, and you wanted to test from 68 grains to 72 grains,...would you shoot 800 groups?
That is 2400 shots? Figured you had a missprint and wanted to walk that statement back.

You were also asked what you used to measure accurately to a 1000th of a grain....you stated the RCBS 1500.

The RCBS has an accuracy of 1/10th grain, not 1/1000th.

As far as incompetence....I have a wall FULL of shooting trophies, including three national 1000 yard champonships. I know for a fact that there are guys on this form who have forgotten more about accuracy reloading than I know, but , am I incompetent? Really?

As far as "helping" the OP......helping him avoid BAD advice is helping, don't you think?

Tod

 

[TOM H]

Interesting. This entire process is so complex. I keep feeling like I'm making wrong decisions for purchases and everyone has differing opinions. I've been hearing from a few people that full length resizing is now the preferred method. I sometimes feel like this stuff is a bit of science mixed with a bit of voodoo and superstition. At this point I just want to get started and stop overthinking it.

Sometimes too much isn't helpful and reloading hasn't change all that much. If you neck size at some point your going to have to FL Size vs FL Size after each firing and it's been that was since I started reloading in the 60's.

When I first started I FL sized for my hunting rifles and I've also hunted with neck sized case fired 3 times. and I never had a problem with either filling my tags.

If I was starting out today I would FL size.

 

[SidecarFlip]

Hello

So, brass is cleaned, chamfered/deburred, neck sized, and primed. I have chosen my bullets and powders and gotten a fairly good idea of my rifle's headspace. Seating dies are adjusted and blanks were made. I've checked the manuals and the manufacturers websites for load data so I'm pretty much armed with everything I need to know.

Now comes the scary part to a newbie reloader... it's time to throw charges. I know my starting load and my maximum load, but how many rounds of each load should I make? Also what is the normal step increment? Is it .5 grains?

Does anyone have any favorite process they can share or have experience with ladder testing?

Thanks!

Candidly, I didn't read any replies. No need really.

If you practice due dilligence and follow Berger Bullets laddering regimen (it's well documented and available on Berger's website,) you can't go wrong.

That applies to any and all bullet manufacturers, you can apply the Berger regimen to anything.

Your comment about your headspace needs some work. Berger clearly explains how to obtain that measurement as well. It's not a guess, it must be correct to ascertain correct jump.

Go do some more reading and absorbing.

 

[el matador]

Can I ask what kind of gun you're loading for? And which brand of brass you're using? Loading for a factory Rem 700 ADL with Winchester brass is quite a bit different than loading for a custom rifle with Lapua brass.

For a beginner I would recommend FL sizing and learning how to properly set up the die for minimal shoulder bump. You want only about .002" of shoulder bump and 1/4 turn of a die is about .018". So get it down to within 1/36th of a turn for best accuracy and brass life.

Use good quality brass so you won't have to worry about neck turning.

In answer to your original question, I like to use roughly 1% increments for my load workup.

My first step is to choose a seating depth. For some rifles you are limited by magazine length or the size/shape of the bullet, so you may not need to fire a single shot to decide on a seating depth. For most rifles I will pick a powder charge near the starting load and shoot a few groups to find a good seating depth. I'll go in .040" increments starting at zero or .010" off the lands and work back to .120" or .150" off.

Once I have an idea of where the best seating depth is I will do powder charges in 1% increments from about 95% to 100% of published max load. Often I'll load one round at 92% and one at 94% just to be extra cautious, and I can use those two shots for foulers and to get on paper. Then 3 shot groups at 95%, 96%, etc. up to 100%. If I don't like any groups after this test I'll try a different bullet or powder. If I am liking one particular load I will try a few groups with slightly different seating depth and/or powder charge until I pinpoint the best load.

I have had the best luck when using bullet/powder combinations that others have had success with. I read the loading manuals and search the forums for good potential combinations.

Keep good records. You can waste a lot of time and money testing the same loads twice if you can't remember what you've already tested.

 

[Bart B]

I don't think smallest groups are a good indicator of a loads accuracy. Especially those with 5 or less shots per group. How does one tell if a small group happens because all the variables are at minimum levels at near perfection or a lot of big ones cancelling each other out?

The biggest group a load shoots is the best indicator of its accuracy.

A good test is shooting several groups and if they're all within a 10% spread of extreme spread, then you've shot enough bullets in each to prove their worth.

 

[Jaxdialation]

Use a chrony. Look at ES, SD and the groups. Done

I don't think smallest groups are a good indicator of a loads accuracy. Especially those with 5 or less shots per group. How does one tell if a small group happens because all the variables are at minimum levels at near perfection or a lot of big ones cancelling each other out?

 

[Bart B]

Laws of physics and chronographing a given load.......

Rifle hand held against ones shoulder at a bench:
Largest velocity spread and standard deviations. Medium average fps for velocity. Several people shooting the same rifle and ammo can get a 100 fps difference in average fps numbers and different spread and standard deviations.

Rifle resting on bags fired in free recoil untouched by shooter:
1/3 to 1/4 the velocity spread and SD of hand held above. Lowest average fps, too.

Barreled action in a fixed mount so it doesn't recoil at all:
Highest average fps. Lowest spread and standard deviation 1/4 to 1/5 or less than hand held rifles. This is how most commercial and arsenal ammo's tested.

Newton's laws.......

 

[Jaxdialation]

Didn't realize Newton did benchrest

I am the only one that shoots my rifles.

Statistics, sample sizes and confidence intervals are applicable here. As are concepts of marginal cost (time, materials and wear and tear) and marginal return. Also consider that even after load development every shot is a new item added to sample size. In other words sampling never stops. Consider the tiny sample sizes used to predict the actions of the entire population in the US, with a high degree of confidence.

My conclusion - 5 shots each of different loads where only one controllable variable is changed is sufficient for me to be confident I've determined a good load. In particular when I can see the changes that occur between loads. If I see deviation in later application, I can investigate. I've never had to do this though.

Laws of physics and chronographing a given load.......

Rifle hand held against ones shoulder at a bench:
Largest velocity spread and standard deviations. Medium average fps for velocity. Several people shooting the same rifle and ammo can get a 100 fps difference in average fps numbers and different spread and standard deviations.

Newton's laws.......

 

[Bart B]

What are those controllable variables?

Which one will increase group size the most?

I've shot enough 5-shot groups with the same load to see at least a 5X spread in group sizes. And the first one is rarely the smallest. Sierra Bullets often sees that same spread shooting dozens of groups testing a lot of bullets shot from rail guns all with the same load.

 

[Jaxdialation]

This is getting silly.

1) You really don't know what things you adjust when developing a load?
2) Don't know
3) Dispersion of sample findings around a mean, doesn't say the mean isn't correct.

Please stop referring to group sizes as the single factor we look at. I said that we look at Chrony data in conjunction with groups, and in conjunction with the results of other load samples. I promise you that Sierra uses sampling methods to test their bullets, otherwise they would have none to sell.

1) What are those controllable variables?

2) Which one will increase group size the most?

3) I've shot enough 5-shot groups with the same load to see at least a 5X spread in group sizes. And the first one is rarely the smallest. Sierra Bullets often sees that same spread shooting dozens of groups testing a lot of bullets shot from rail guns all with the same load.