How do I determine a starting load given limited load data?

[AK3lms]

Ok, guys, I've read quite a few threads over the years and respect your knowledge.

I'm pretty new to hand loading, so this may be an easy answer for many of you. Please excuse my ignorance.

I'm sure many of you are experiencing the struggle of finding supplies. In an effort to secure powder for my hunting loads, and not being able to find anything near me, I ordered the only thing I could find from Graf and Sons... Nobel Sport Vectan Tu7000. I am loading ammo for .243 Win and 7mm-08 Rem.

Like the others whom I've read, I have been unable to find much load data for the Vectan powders. My question is this: They give load data for a 90 gr. bullet and a 100 gr. bullet. I am wanting to load a 95 gr. Nosler Ballistic Tip. Can I split the difference between the two published starting loads and be ok?

Also, are there any threads that I should read to give me a better understanding reading load data? Maybe some basics on understanding the different load manuals.

Thanks in advance.

 

[Pat Riot]

I found load data here:
https://www.grafs.com/retail/catalog/tech-resource/technicalResourceId/20

Maybe this will help?

 

[tightgroup tiger]

If you have 100gr load data and 90 gr load data for the same bullet, you should be able to interpolate your starting load for the same bullet in 95gr. (split the difference of the starting loads for each).

If the bullet brand or design is not the same, then find the load data for the next heavier bullet like the bullet your using, and use that start data to start working up your load and watch for pressure signs like flattened primers, or heavy bolt lift, that will tell you when you need to back down.

Don't ever use data from a lighter bullet for use with a heavier bullet, that will get you in trouble every time,

A lighter bullet breaks inertia easier so it takes more powder to get the pressure up to make the desired pressure/velocity your after.

A heavier bullet will build more pressure with a lighter charge, because it is harder to get it to break inertia so the pressure spike is higher with a lower charge than with a lighter bullet with the same powder charge.

So if you use the lighter bullet data with a heavier bullet, you can go over the pressure design limit of the gun and make a grenade.

 

[AK3lms]

If you have 100gr load data and 90 gr load data for the same bullet, you should be able to interpolate your starting load for the same bullet in 95gr. (split the difference of the starting loads for each).

If the bullet brand or design is not the same, then find the load data for the next heavier bullet like the bullet your using, and use that start data to start working up your load and watch for pressure signs like flattened primers, or heavy bolt lift, that will tell you when you need to back down.

Don't ever use data from a lighter bullet for use with a heavier bullet, that will get you in trouble every time,

A lighter bullet breaks inertia easier so it takes more powder to get the pressure up to make the desired pressure/velocity your after.

A heavier bullet will build more pressure with a lighter charge, because it is harder to get it to break inertia so the pressure spike is higher with a lower charge than with a lighter bullet with the same powder charge.

So if you use the lighter bullet data with a heavier bullet, you can go over the pressure design limit of the gun and make a grenade.

Thanks, Tightgroup! This is why I posted this question here. I knew you guys would help me understand the basics of reloading without making me feel like a complete idiot. Thanks for the knowledge.

Pat, thanks for the info! I might have missed this. I’ll check it out and find out what I can.

 

[AK3lms]

This is the data that I was originally referencing, and Pat linked to. It’s from Nobel Sport.

Tightgroup (or somebody else), the way I understand your reply, in order to load for a 95 gr Nosler BT, I could start off with the 100 gr load data and be safe. Correct?

And does bullet construction as far as Ballistic Tip or Partition or Accubond matter as far as the load is concerned? I understand that cast or jacketed matters, but as long as I’m shooting a jacketed bullet of some kind (SST, ELD-X, Interbond), is it only the weight that matters? I also see load data is different for solid copper bullets, but I don’t understand why, exactly. I’ve read the first part of the Lee Manual, but obviously I don’t have a grasp on all of this yet. I have stayed strictly printed load data, because I don’t want to injure myself, my guns, or anybody else.

Sorry for the rapid fire questions. These have just been running around in my head and I figure you guys could help me understand this better.

 

[Bfh_auto]

View attachment 964845

This is the data that I was originally referencing, and Pat linked to. It’s from Nobel Sport.

Tightgroup (or somebody else), to load for a Nosler BT, I could start off with the 100 gr load data and be safe. Correct?

Yes it should be safe using the 100 gr data.
You are on your own on deciding your max charge because it will probably be somewhere between the two data sets.
Look at the difference between the 85 and the 90. Then compare that to the difference of the 90 and 100.
You'll see that bullet design or testing parameters causes the 90 to have a higher charge than the 85.

 

[rfwobbly]

Another way to look at it...
Consider that you have a den window that looks out into your yard. When you sit on your couch you can see 48 feet of back fence out that window. Your spouse shifts the couch 3 feet over. You can now see a different portion of the back fence, but you still see only 48 feet. Despite your vantage point, your range is still 48 feet.

It is very similar with powder. The Starting Load (the couch position) may vary with your bullet weight, but the Load Range (viewing width) remains fairly constant.

• Consider the Load Range for either 90 or 100gr bullets is roughly 6.1gr. Therefore, 36.3 (Starting) + 6.1 (Range) = roughly 42.4gr Max

• If you had (say for instance) a 93gr or a 107gr bullet, then you might want a different Starting Load, but your Load Range would still be roughly 6.1gr.

 

[Dudedog]

And does bullet construction as far as Ballistic Tip or Partition or Accubond matter as far as the load is concerned?

Yes, but not as much as bullet weight.
2 bullets of the same weight may (will) have a different amount of the bullet actually touching the bore (different amount of friction) so different MAX, one bullet maybe "harder" than another.
Monometal bullets Barnes, GMX etc tend to be longer (take up more space in the case, more friction) and generally require lighter charges than a cup and core bullet of the same weight

Different jacket thicknesses, different lead composition, varying lube grooves, different bearing surface lengths - and a handful of other parameters will influence how a bullet resists traveling down a bore.

Notice in your above data the 85gr bullet has lower charges than the 90.
If it was me I would start with the 100gr data and work up.

 

[tightgroup tiger]

And does bullet construction as far as Ballistic Tip or Partition or Accubond matter as far as the load is concerned? I understand that cast or jacketed matters, but as long as I’m shooting a jacketed bullet of some kind (SST, ELD-X, Interbond), is it only the weight that matters?

Like Dudedog said, the bearing surface will affect the friction of the bullet so that has to be taken into consideration. But weight by itself isn't the only factor as the weight dictates the length of the bullet, which usually dictates the frictional coefficient of the bullet to the barrel.

I also see load data is different for solid copper bullets, but I don’t understand why, exactly. I’ve read the first part of the Lee Manual, but obviously I don’t have a grasp on all of this yet.

With all copper bullets you much consider that the copper doesn't have near the mass as lead so to make weight the bullet must be much longer for a given caliber/weight rating.
That's why copper bullets are always so much lighter than lead bullets( cup and core bullets) and the load data is so different. With copper bullets being lighter than lead, you can't add diameter to the bullet to make up for the difference in mass so you must add length.
So if you add length, the rifling's in the barrel must be faster to accommodate the extra length difference between the solid copper and the cup and core (lead bullet) because the longer the bullet, the faster you have to spin it to stabilize it in flight, and it also won't chamber in the magazine or the chamber of the rifle being it's to long.

So the solid copper bullets will always have a lighter weight to keep the length of the bullet as close to the length of the cup and core bullet so the rotation speed of the copper bullet stays similar to the rotation speed of the cup and core (heavier) bullet.

Solid copper or MonoMetal bullets have a different hardness than jacketed, but they are usually close to the same length. Copper is so much lighter so the pressure curve isn't the same as it would be with cup and core bullets. That and with the lighter weight bullets we have to consider the fact that primer, by itself, may unseat the light bullet before a slow powder has time to get up to pressure.
Smokeless powders rely on pressure to make the powder burn correctly, and that comes from
You can actually have two different pressures spikes in the same event, the primer pressure event, starting the bullet on it's way, and the powder pressure event that comes later and has to catch up to the bullet and that can damage your barrel.

So you can not use the same interpolation with an all copper bullet, as you can with a cup and core (lead) bullet with the same powder. There is just to much difference in bullet weight which affects pressure, which affects the burn characteristics of the powder being used.

 

[35 Whelen]

Ok, guys, I've read quite a few threads over the years and respect your knowledge.

I'm pretty new to hand loading, so this may be an easy answer for many of you. Please excuse my ignorance.

I'm sure many of you are experiencing the struggle of finding supplies. In an effort to secure powder for my hunting loads, and not being able to find anything near me, I ordered the only thing I could find from Graf and Sons... Nobel Sport Vectan Tu7000. I am loading ammo for .243 Win and 7mm-08 Rem.

Like the others whom I've read, I have been unable to find much load data for the Vectan powders. My question is this: They give load data for a 90 gr. bullet and a 100 gr. bullet. I am wanting to load a 95 gr. Nosler Ballistic Tip. Can I split the difference between the two published starting loads and be ok?

Also, are there any threads that I should read to give me a better understanding reading load data? Maybe some basics on understanding the different load manuals.

Thanks in advance.

I guess I'm old school, but I learned most of what I know from reading reloading manuals as well as books on the subject. There is so much misinformation out there that it makes me cringe to think that new handloaders are depending on internet forums and YouTube videos to learn how to handload.

I strongly suggest you get a manual or two and maybe even a book on handloading. Another excellent resource is www.loaddata.com. A subscription thereto access to some fantastic articles from the pages of Handloader and Rifle magazines.

35W

 

[tightgroup tiger]

I guess I'm old school, but I learned most of what I know from reading reloading manuals as well as books on the subject. There is so much misinformation out there that it makes me cringe to think that new handloaders are depending on internet forums and YouTube videos to learn how to handload.

All of us older guys learned from books and handed down information.
And now we are handing it down again.
I would rather he ask before guessing about what he is doing.

 

[rfwobbly]

All of us older guys learned from books and handed down information.

To paraphrase Sir Isaac Newton... 'We are all standing on the shoulders of giants."
Thank you Lord for those before me who cared enough to share their knowledge, and who drug me (often times leaving 2 black heel marks) out of my own ignorance.

 

[AK3lms]

Thanks, Titegroup and Dudedog, that makes sense.

Whelen, I agree with what you are saying, and I have read some manuals, but sometimes other voices can cast a different light on the subject, making it easier to understand. I appreciate the knowledge the guys on this forum have, yourself included.

I always try to compare the advice given with what I know (which is admittedly limited) and make sure it lines up.

I definitely understand that I can’t use the load data for solid bullets. I will use the load data for the 100 gr. and work up from there. I don’t like pushing the limits. I’m not trying to get hurt or hurt someone else, or my firearm.

BTW, I did just sign up for www.loaddata.com. Looking forward to learning more about handloading.

 

[35 Whelen]

Don't get me wrong there's a vast amount of knowledge here and elsewhere. But I've also seen some blatant misinformation here, some dangerous, other not so much.

So, be careful and enjoy!

35W

 

[lordpaxman]

I guess I'm old school, but I learned most of what I know from reading reloading manuals as well as books on the subject. There is so much misinformation out there that it makes me cringe to think that new handloaders are depending on internet forums and YouTube videos to learn how to handload.

As did I but I also asked other reloaders and mentors a lot of questions F2F. Nowadays that’s via this forum. While there’s a lot of information and misinformation, as with any advice, or any set of reviews, you need to apply a certain modicum of common sense as well.
As to the OP’s question, it’s a valid one as most reloading manuals don’t delve into the interpretive realm. It’s very rare that I’ve been able to find a published load data for my gun v, case w, powder x, bullet y, and primer z. Good luck.