How dishonest is published data!

[ARlife4me]

I will state that Berger made a typo and came forth with it about their 90gr 22cal in 223rem @ 2.260". Way toooooooooooooooo short for a long bullet. Having may 26cal bullets I decided to do some pre 6.5prc coal (2.830" max) for upcoming loads. I started with Sierra. 107mk stated in the book @ 2.955" . Maybe 20 thou inside the neck not counting the boat-tail. Their 123mk were not much any better at the same length. None of the 2 could fully be seated (bearing surface) in the neck. Next was Nosler. Same issues with their data on oal. Their 123cc needed to be 2.800 and 130rdf needed to be 2.830" (worked for me). Lapua was on the block next. 108scenar (no data at VV), but the 144fmj was fine. On to Hornady. Their 123sst listed 2.900", again toooooo long. The 130eld-m was closer and I could shorten it 120 thou less and be fine. Regardless of my mag limitations the data was wrong on most parts unless you want to give it a very tight crimp!

 

[Mikecr]

It's good that you don't blindly rely on anything. That you validate what you're doing.
None of these published errors should be a concern for you.

I haven't looked at published or posted reloading information since the invention of QuickLoad. That's been a long time now.
But QL baseline data is no more reliable than manuals. I still validate everything, like you.

Perhaps a golden reloading rule.

 

[Old Rooster]

Less experienced reloaders are at the mercy of the stated data and may not have the experience folks here have.
The one's just starting to reload needs to find a mentor.

 

[Zen Archery]

When I got into it many moons ago I was told to look at a minimal of 3 different manuals to get an idea of where to start.

Then start low and work up.

I preach the same thing to all newbies.

 

[Old Rooster]

Amen Zen Archery.Your a good mentor!
I write down loads someone else has had sucess with but I NEVER load that and shoot it.
Like you I always work up for safety sake.

 

[doverpack12]

If you are using new brass there is a good chance your brass grows and neck lengthens which could help those bullets have more bearing surface in the neck. Doesn't mean the info you discovered will change but it possibly could fix a few.
I'm not sure I am fully understanding what you are describing though. What is the max 2.83" you are referring to?

 

[ARlife4me]

If you are using new brass there is a good chance your brass grows and neck lengthens which could help those bullets have more bearing surface in the neck. Doesn't mean the info you discovered will change but it possibly could fix a few.
I'm not sure I am fully understanding what you are describing though. What is the max 2.83" you are referring to?

2.830" is the longest oal for the cartridge due to mag restrictions. The Sierra 107mk (minus boat-tail) would only be inside the neck around 20 thou. Not enough bearing surface for neck tension or safe seating for that matter. The neck would need to grow 200 thou.

 

[cohunt]

All reload data is input by humans--- not sure if you've heard yet or not, but humans make mistakes.

 

[ARlife4me]

All reload data is input by humans--- not sure if you've heard yet or not, but humans make mistakes.

With what Berger published as an inaccuracy, Sierra probably did also. I did call Berger about the data, but haven't called Sierra yet. Some data is intentionally inputted wrong. Nosler is a big example, especially where bc is. They come out with a new bullet in the same weight (within 2 grains) and all of the sudden the older 1 gets lowered. Was it a printing error on a massive scale or just for marketing!

 

[cohunt]

With what Berger published as an inaccuracy, Sierra probably did also. I did call Breger about the data, but haven't called Sierra yet. Some data is intentionally inputted wrong. Nosler is a big example, especially where bc is. They come out with a new bullet in the same weight (within 2 grains) and all of the sudden the older 1 gets lowered. Was it a printing error on a massive scale or just for marketing!

Bc changes with twist rate and speed--- there has never been a "set" number for bc, its a dynamic number---- but in general it works for most shooters. Also once doplar started being used- the numbers are now closer

 

[doverpack12]

2.830" is the longest oal for the cartridge due to mag restrictions. The Sierra 107mk (minus boat-tail) would only be inside the neck around 20 thou. Not enough bearing surface for neck tension or safe seating for that matter. The neck would need to grow 200 thou.

Saami max coal is longer than 2.83" any reference to tge 2.83" length is specific to your rifle and not relative to correct or incorrect published data.
Load data has attorneys all over it before being published, to find an error in a single cartridge across many of the major bullet manufacturers is a pretty big reach.
I would come back to your brass and question if the oal of the brass is in spec especially if new because it's often short until fired and sized once. That would directly relate to the depth of bearing surface you are observing in the neck of your brass

 

[ARlife4me]

Bc changes with twist rate and speed--- there has never been a "set" number for bc, its a dynamic number---- but in general it works for most shooters. Also once doplar started being used- the numbers are now closer

Well, I'm sure their testing was all done at the same place with the same gun (if actually done). So, same altitude, location and maybe (most likely) different temp. So, no excuse on their part!

 

[ARlife4me]

Saami max coal is longer than 2.83" any reference to tge 2.83" length is specific to your rifle and not relative to correct or incorrect published data.
Load data has attorneys all over it before being published, to find an error in a single cartridge across many of the major bullet manufacturers is a pretty big reach.
I would come back to your brass and question if the oal of the brass is in spec especially if new because it's often short until fired and sized once. That would directly relate to the depth of bearing surface you are observing in the neck of your brass

I have new unfired brass and Hornady modified case in 6.5prc for comparisons. Cases are at 2.020" (2.015" is specified trim length). Honest measurements. Looks like Sierra is way off and that's just getting the start of the bearing surface at the shoulder/neck conjunction.

 

[Boss Hoss]

Bc changes with twist rate and speed--- there has never been a "set" number for bc, its a dynamic number---- but in general it works for most shooters. Also once doplar started being used- the numbers are now closer

Very true---many people are clueless about this.