The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools
Old May 9, 2007, 12:38 AM   #1
RSublime4Life
Senior Member
 
Join Date: March 28, 2007
Posts: 146
Variations between manuals?

Still reading as much as I can before I get started. I was comparing load data between manuals tonight and I noticed that some loads vary quite a bit from one manual to the next. I realize that test equipment varies from one to the other but I would think they would have similar results for the most part. Of the manuals I have it seems that the Hornady has the hottest loads of the bunch. I also realize I am new to this stuff and still learning so maybe I am wrong about how different they may be. Anyway here is an example: In the Hogdgdon manual for a 185 gr. Hornady JSWC its list the max load for Titegroup at 5.2 grains with a velocity of 946 fps. In the Hornady for the same bullet and powder it list the starting load at 5.1 grains with a velocity of 850 and the max load at 6.6 grains and a velocity of 1050. That seems like a huge difference! Unfortunately the other manual I have, Lyman, doesn’t list a load for Titegroup so I don’t have a 3 source to check. What are your findings as far as variations between the manuals for the same loads? Does Hornady run hotter then the rest? Or are the rest a bit conservative?

-Russ

P.S. Yes, I realize I shouldn't start out with the hot loads and I don't intend too. It is only an observation made about the data.
__________________
Names Russ, feel free to use it.

NRA Life Member
RSublime4Life is offline  
Old May 9, 2007, 05:51 AM   #2
Bullet94
Senior Member
 
Join Date: September 8, 2004
Location: Kansas
Posts: 723
Quote:
RSublime4Life
What are your findings as far as variations between the manuals for the same loads?
I find they are not the same loads. The components are different or the OAL’s are different or the test equipment is different.
__________________
PRO-SECOND AMENDMENT - Live Free or Die
Bullet94 is offline  
Old May 9, 2007, 06:41 AM   #3
qajaq59
Senior Member
 
Join Date: November 15, 2005
Posts: 139
That's why most of us begin with the starting loads and work up until we get to an accurate load. We rarely have a clue what rifle they were using to work up their loads, so it is the safest way to go.
qajaq59 is offline  
Old May 9, 2007, 11:17 AM   #4
RSublime4Life
Senior Member
 
Join Date: March 28, 2007
Posts: 146
Quote:
I find they are not the same loads. The components are different or the OAL’s are different or the test equipment is different.
In the example I gave the bullet, powder and OAL were the same. Don't know about the case or primer. I am sure the test equipment was different.


Quote:
That's why most of us begin with the starting loads and work up until we get to an accurate load. We rarely have a clue what rifle they were using to work up their loads, so it is the safest way to go.
Agreed. Although in the example I gave the starting load in the Hornady manual was just 0.10 grain less then the max load from the Hogdgon manual. So starting from the lowest load in the Hornady manual is basically like starting at the max in the Hogdgon. That seems like an extreme variant.

Again I am new to reloading so forgive me if my interpitation of the data is off or if my question seems dumb to some of you. But you never know if you don't ask, right? Thanks for your help!

-Russ
__________________
Names Russ, feel free to use it.

NRA Life Member
RSublime4Life is offline  
Old May 9, 2007, 01:41 PM   #5
qajaq59
Senior Member
 
Join Date: November 15, 2005
Posts: 139
Well if it is dumb then we're in the same IQ class because I asked the same thing about a year ago when I saw 3 totally different loads for the same 30-30 bullet and powder in 3 different manuals. And I've been loading since the 60s. I just never happened to notice it before.

I chose the lowest of the bunch and started there. I do think there is some leeway on the published MAX loads, but I'm not about to be the one that finds out that I'm wrong. I'm quite fond of these fingers.

Never hesitate to ask questions. And if you don't get an answer that you understand, then ask again. As far as I know that why these forums are here.
qajaq59 is offline  
Old May 9, 2007, 01:52 PM   #6
Number 6
Junior member
 
Join Date: October 3, 2002
Posts: 921
Check, recheck and check again

Quote:
Again I am new to reloading so forgive me if my interpitation [sic] of the data is off or if my question seems dumb to some of you. But you never know if you don't ask, right? Thanks for your help!
NEVER rely on just one manual if you can help it!

I once found an error in an Accurate on-line manual. The charges for one powder had been placed in the data for another powder. I e-mailed Accurate, which corrected the error.

When I get load data from multiple sources, I toss the highest and lowest loads. In the alternative, I add the highest loads and divide the total by the number of sources to get an average, and do the same for the lowest load.

I tend to do pistol loads in .2 grain increments; rifle loads in .4 or .5 grain increments. I make 10 pistol / 5 rifle of each step and measure the group size for each while checking for the primers and cases for signs of excessive pressure.
Number 6 is offline  
Old May 9, 2007, 02:13 PM   #7
Shoney
Senior Member
 
Join Date: February 21, 2002
Location: Transplanted from Montana
Posts: 2,311
The only dumb question is the one unasked!!!!!!!!

Pressure, whether derived from "Strain gauges" or copper crushing tests is how the manuals determine their minimum and maximum loads. Combinations of factors can cause great variances in pressure. Here are a few factors:

Primer: strength, brisance - is a measure of the rapidity with which an explosive develops its maximum pressure
Barrel: length; tightness of bore; height of the lands; distance of bullet to lands; temperature of barrel;
Bullet: bearing surface of bullet, alloy of bullet; shape of bullet;
Brass: new/used elasticity; manufacturer, volume;
Powder: new, aged, old, batch powder was from;
Weather: ambient air temp., barometric pressure, humidity; elevation above sea level
Other: I am sure I have not listed all

Now, mix and match them. Anyone care to calculate the number of possible combinations?

All load manuals have data well under the SAAMI pressure specs (lawyer driven data). Looking for pressure signs in rifle bottleneck cartridges is a good (not foolproof) indicator of safe loads. There are no reliably safe pressure signs for straight wall pistol cartridges.
__________________
I pledge allegiance to the Flag - - -, and to the Republic for which it stands….Our Forefathers were brilliant for giving us a Republic, not a democracy! Do you know the difference??? and WHY?http://www.wallbuilders.com/LIBissue...les.asp?id=111
Shoney is offline  
Old May 9, 2007, 02:38 PM   #8
Edward429451
Junior member
 
Join Date: November 12, 2000
Location: Colorado Springs, Colorado
Posts: 9,494
If you're loading lead bullets pay close attention to the size of the bullet they used in the manual also. I got max load velocity from a starting load powder charge once and in investigating the load carefully to figure out why I noticed that my bullet was .002 larger than what they had sized too.
Edward429451 is offline  
Old May 9, 2007, 02:49 PM   #9
TrimixDiver
Junior Member
 
Join Date: March 15, 2007
Location: Central Kentucky
Posts: 12
Assuming the same powder only. Cases from different manufacturers have different wall thicknesses, hence different internal volumes. Primers may differ in from maker to maker. Bullets of the same weight from different manufacturers have different shapes which will give them more or less bearing surface. The amount and type of crimp will also play a role in pressure. Cartridge OAL will play an important part as well with a deeper seated bullet giving a cartdidge case less volume. A longer OAL will give a cartridge case more volume. This holds until you consider the proximity of the bullet to the rifling lands in the barrel. Touching the rifle will give you hight pressure than not touching the rifling.

Outside of the cartridge you have the weapon or receiver the load was tested in. A universal receiver with a minimum SAAMI spec chamber will produce different pressures than a production rifle. Difference in the barrel itself will cause pressure/velocity differences.

Then you get into the testing of the pressures themselves. The different makes/brands of equipment/sensors that measure the pressures. The difference between piezo-electric transducers to copper or lead crushers. You get pressures in psi, c.u.p. or l.u.p. all of which are not interchangeable.

Finally, if everything else is exactly the same, you can still have a variation in the powder from lot to lot.

I am sure that there are other factors that I have missed and that other posters will bring up.

Basically, this is why anytime that you change a component you should back your load off and check things out.

As a side note - I have had pet loads that give outstanding accuracy change dramatically for the worse simply by changing the primer(manufacturer).
TrimixDiver is offline  
Old May 9, 2007, 03:35 PM   #10
RSublime4Life
Senior Member
 
Join Date: March 28, 2007
Posts: 146
Thanks for the input! So with all that said, would you be comfortable starting with the beginning load in the Hornady manual knowing it was basically the max load listed in the Hogdgon?
__________________
Names Russ, feel free to use it.

NRA Life Member
RSublime4Life is offline  
Old May 9, 2007, 04:55 PM   #11
Number 6
Junior member
 
Join Date: October 3, 2002
Posts: 921
Quote:
So with all that said, would you be comfortable starting with the beginning load in the Hornady manual knowing it was basically the max load listed in the Hogdgon?
NO!

Too great a discrepancy. I would check other sources; Speer, Lyman and the online information from the propellant manufacturer.
Number 6 is offline  
Old May 9, 2007, 05:05 PM   #12
RSublime4Life
Senior Member
 
Join Date: March 28, 2007
Posts: 146
That's kinda how I felt. The 3rd manual I have is the Lyman but it doesnt list Titegroup in their data.
__________________
Names Russ, feel free to use it.

NRA Life Member
RSublime4Life is offline  
Old May 9, 2007, 05:34 PM   #13
dgc940
Senior Member
 
Join Date: September 15, 2005
Location: Graham Texas
Posts: 258
Let me tell you what I ran into this past fall. I purchased the Hodgdon annual reloading manual a magazine they put out every year with the latest loads for new powders and bullets. I wanted to load some noslers with benchmark powder in my 243 so I started .5 grain above the bottom load and almost blew my bolt into the next county on the first shot! I called Nosler and they said it must be a misprint because it did not sound right to him. He had the same manual in front of him. then I called Hodgdon to report it and the guy was a real smart ass about it and said they made no mistakes and it must be me or my rifle. and look at a bottle of h380 and the load for 22-250 on the bottle it is a fairly hot load and its probably OK for seasoned loaders that are in the know. but what about a newcomer to the hobby? they should not list a hot load on the bottle. Needless to say I backed off 1.5 grain below the bottom and it shot very well with the Nosler in my .243
__________________
Some people say what they think!
Some say what they know!
Then there's those that think they know what they are saying!
dgc940 is offline  
Old May 9, 2007, 06:15 PM   #14
Trapper L
Senior Member
 
Join Date: November 20, 2006
Location: South Texas
Posts: 804
The manuals are a guide, not an absolute. The bullets are usually a different design and the bearing surface makes a difference in the data. Take a Hornaday 30 cal HPBT and compare it to a Speer flat base spitzer in 150 gr. Not even close to the same bearing surfaces. Different jacket materials makes a difference. Then you have the test equipment and the temperature changes over the test period, humidity and barometric pressure changes, all plays into what the test results will be. Hardly ever can a lab duplicate the data back to back on the same day with the same components. The data supplied is usually the bottom results of the multitude of tests run. The more important factor is your components. Use a different primer, seat the bullet deeper, use a different lot of powder, fire it in a gun with a tight chamber, rough barrel, hot day, and the list is endless. They are guides, not absolutes. You never fire handloads without checking for pressure- even after having great results and have used the data for years. Always check for signs of pressure even if it is minimum loading data. And don't expect that your gun will shoot the published max loads or even close to max. I have a 6.5x06 that if you load max loads you'll probably be wearing some of it. It has a very tight chamber and barrel. You won't get to 10% below that of max data and you'll have primers falling out of brass from too much pressure. Start low and work up. It beats starting high and getting laid low.
Trapper L is offline  
Old May 9, 2007, 06:34 PM   #15
rwilson452
Senior Member
 
Join Date: June 10, 2004
Location: Tioga co. PA
Posts: 2,359
Some time ago I decided to try some H380 in my 22-250. I looked up the load in my old Hodgdon manual. Max load was 38gr. Then I looked it up in the Hodgdon annual Max of 41gr. WHOA! I called Hodgdon. Yep 41 gr is the new max. Well I worked up to 40 gr and didn't like the pressure signs and accuracy was falling off. I suppose I could have fired a 41 gr load and not had any real bad effects. But I was after and accurate load. it turned out to be 39 gr. one full grain over the old max load. moral of the story is start at the beginning and work up watching for signs of pressure. ALWAYS!
rwilson452 is offline  
Old May 9, 2007, 06:40 PM   #16
Edward429451
Junior member
 
Join Date: November 12, 2000
Location: Colorado Springs, Colorado
Posts: 9,494
+1 to what trapper said. It amazes me when people get on here and say they started 10 or 15% below max as if that is a starting load. Always, always start at the starting load. (Or in your case I might just start 1/2 gr below the starting load since there is so much discrepency).

Take good notes on everything so you will be able to figure something out later. You really need a chrony to see what your loads are doing. I guessed for so many years and am now finding out that some loads were hotter than I realized, and some were not. I feel like I'm back at square one again. With a chrony, you can compare what you get with what the book says and figure where you're at. Like that one starting load that gave me max velocity...That pressure must be up there. I know that velocity does not necessarily equate to pressure absolutely, but I think it's a pretty good indicator.
Edward429451 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:43 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.13283 seconds with 9 queries