Runnout and Bullet sorting

Care to share how ?
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find a velocity flat spot using Erik Cortinas 100 yard load development

measure powder to + or - .01 gns on A&D

seat primers to same depth using a http://bulletin.accurateshooter.com/2018/10/darrell-holland-upgrade-for-rcbs-bench-priming-tool/

case prep - https://thefiringline.com/forums/showthread.php?t=611654

biggest difference in my shooting has been made by putting thousands of rounds downrange @ 300 plus along with tens of thousand of .22 LR @50 - 200. Reloading is simple, consistent shooting techniques and wind reading are not so easy
 
so basically anything other than what you covered in the other thread and here is enough for consistent accurate ammo and range practice. Agreed, other than flat spot velocity and +/- .01 gn powder charge. Haven't looked into yet. I used to do .05 but now 1.0.
 
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here is some of Cortinas achievements

https://www.lapua.com/teamshooters/erik-cortina/

Erik Cortina is one of the top F-Class shooters in the US, and has had tremendous success at National and World F-Class Championships. Erik is Texas State Long Range Champion 3 years in a row and has also won a bronze medal in the World Championships. He also placed 3rd in F-Class Nationals. Recently, Erik also began shooting competitively in PRS in 2018, and won his first match at the SoTex club match on July 23. Erik also has his own his own YouTube Channel with informative videos on shooting and reloading.
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So when was the last time you shot in competition and how did you do?
 
I've never had a bullet comparator, see no use for one. At one time just to be sure of bullet weight I weighted a couple box's of SMK bullet's. Boring as hell! Every one was exactly the same! Do it with other bullet's and there will be some difference but even then a good well bedded rifle will shoot them into an inch or well under! If I were to go into business for myself I'd make reloading tools. Unbelievable how many tools reloader's buy that they think they need. It's a wonderful era we live in! For what ever reason we need a rifle that will shoot 1/2" groups to hit the 8" vital zone of a big game animal at 200 yds or less! Words of experience as I do it myself and haven't a clue why! Without all the high dollar tools I still have three hunting rifles that will group at 1/2" at 100yds and the rest except for one will go about 3/4"! I don't shoot at game animals at long range or rather long range for me is 300 yds and I actually shot a deer at 330yds one time just to say I did it. My animals are usually shot at 225yds or less!
 
Yeah there are alot of ways that are unnecessary to achieve accuracy and the level depending on application. But to achieve it isn't just a good well bedded rifle, that's a start. I bought a COAL gauge and have been using it along with the comparator. Just last night I decided to give a threaded case that is used along with the COAL gauge a little bit of neck tension to be used to set my seater die instead of having the neck loose and measure the bullet while in the gauge with the comparator. The bullet is still able to be pushed with the plastic insert inside the body of the gauge. Two tools are necessary to do what one can do, two calipers too to save time swapping out tools between one caliper! So yeah I have three ! But I need the third for my headspace gauge when setting back shoulders, that's a must. I'd like to get a die with a dial indicator for that. Why need 1/2 inch rifle? Less game to harvest is the best answer. I now people who had to pass up shots from partially hidden deer, and having that smaller window of time too.
 
For a little while I was confused about what this thread was about.

I think maybe the OP is not clear on what the term "runout" means.

Generally,the part being checked for runout is rotated around an axis,such as between centers or in a collet.

A dial indicator placed on the part as it rotates will show runout. It is often expressed as "TIR",or "total indicated runout"

Put simply,its about wobble.

I think the OP is talking about a length,perhaps as measure from a circular datum. Is that true?

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Bart,for approx 85 yrs old,you seem pretty sharp to me!

It COULD be what has changed about shooting in the last 15 or 20 years is many of us are just learning some of what you knew 20 years ago.
 
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Hounddawg--I love watching Erik's video's--I bought my favorite t-shirt as a result of that "don't chase the lands" video. But after watching it I realized isn't he sorta splitting hairs--since he's basically "chasing the jam", more or less the same concept with a different datum?
 
It was actually two questions, you were the first one to notice, I was wondering if the ogive difference of +- .0004 makes a difference in runnout of the COAL.
 
If Runout on the seated bullet is what you mean the as long as you indicate on a flat surface of the bullet that’ll give you the right reading other wise the bullet run out will not be effected where the bullet is seated
 
No commercial bullet runout gauge orients the bullet to the dial indicator like cartridges align bullets to the bore axis when fired.
 
BartB

No commercial bullet runout gauge orients the bullet to the dial indicator like cartridges align bullets to the bore axis when fired.
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Hey Partner....your right, it doesn't orinet a bullet to be aligned to the bore axis.. that is correct. It checks to see how concentric everything is.

What I am conveying is the bullet is inline/concentric with the case. You assume everybody has custom F class tightly reamed chambers with custom dies to match. Maybe some do maybe some don't, but if I were you I wouldn't assume either way. ASK.

I do with what I have, and get cartridges as close as I can to being concentric and inline with the chamber/bore as I can. I have custom nothing. I have a bedded Winchester M70 loading with RCBS FL sizer w/o and expander ball, Sinclair expander mandrel, and a Forster BR seater and VLD stem. At 100 yards I can get 1/2 inch group and neck turning 1/4 inch group.

Anything else?
 
I know the highest scores competitive shooters produce are not all from tight custom chambers.

What centers the front of the cartridge in the barrel when the round fires?

What's the size of your largest groups with the same load that shoots the smallest groups?
 
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What's the size of your largest groups with the same load that shoots the smallest groups?
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I shot the same load that had a larger group, 1/2 MOA than the one that shot a smaller group1/4 MOA. The smaller group was neck turned, the larger group wasn't neck turned.


What centers the front of the cartridge in the barrel when the round fires?
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It's the case shoulder centering in the chamber shoulder that centers the front end of the cartridge in the chamber. Case necks are free floating with some amount of neck clearance.

Again, Bart, having a concentric case neck, and bullet concentricity does not orient the alignment or axis of the bore, I understand that. It's appreciated what your conveying about what really orients the bullet to the axial position of the bullet/barrel. A concentric neck and bullet being established in loading a cartridge is important to have consistent neck tension, that's my only point here. Thanks for your input. It's appreciated.
 
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I shot the same load that had a larger group, 1/2 MOA than the one that shot a smaller group1/4 MOA. The smaller group was neck turned, the larger group wasn't neck turned.
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Those aren't the same load, just the same components except for the case neck.
 
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