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Reloading Manual Data query

3K views 14 replies 15 participants last post by  papajohn428 
#1 ·
I've been reading a couple of reloading manuals and was wondering if someone could answer a couple of questions,

1) Why is there such a sizable difference in the reloading data for same load between differnet manuals ? I'm comparing the current Speer and Lee manuals.

2) If a manual refers to a 158 grain lead bullet is it reasonable safe to assume that the same load applies for different styles of bullets such as RNFP, SWC etc ?
 
#2 ·
1) I assume you are talking about the differences in velocity and pressures listed. The differences are due to the test barrel setup used to gather the data. The Speer manuals (and several others) list the test barrel length although the Lee manual doesn't. Almost all of the test setups use a sealed barrel (single shot type) instead of a revolver, mostly for safety and an easier setup for testing pressure. The listed loads will be within safe pressure limits for guns in good condition, except where noted (T/C specific loads vs standard loads as an example). You will still need to check the velocity for your gun if you want to know exactly how fast they are going.

2) This is not a valid assumption. Lead bullets are easier to push down the barrel than jacketed bullets. It is generally safe to use jacketed bullet loads with lead bullets, but not the other way around. I would not recommend changing the bullets on any load, but I am a safety nut (at least as much as a shooter can be :). If you can't find a load for the bullet you want to use, check the LoadSwap site and get some more manuals. Most of the powder manufacturers have downloadable (PDF) versions of their manuals available, so it is cheap and easy to have these available. Lyman has some outstanding information available in their books that are well worth the price for them. And Marshalll's book has a lot of very good information in it as well, just not specific loads.

Books are cheap compared to the cost of an arm or an eye, but the fact that you asked indicates you have alreadty figured that one out ;)
 
#4 · (Edited)
BenA said:
1) Why is there such a sizable difference in the reloading data for same load between differnet manuals ? I'm comparing the current Speer and Lee manuals.

2) If a manual refers to a 158 grain lead bullet is it reasonable safe to assume that the same load applies for different styles of bullets such as RNFP, SWC etc ?
The discrepancy between loading manuals has always bothered me especially when one manual's minimum load approaches another's maximum. Whenever this happens, I consult the powder manufacturers recommendations and go with that. I have found that the manufacturers tend to be conservative. Most of us are not trying to load to the limits of pressure and velocity so we are somewhere safely close to the middle range of the loading manuals recommendations. Loaders who are looking for the extremes should proceed cautiously.

For a given caliber and weight LEAD bullet, it is reasonably safe to apply the same load regardless of bullet shape. This is assuming that you are NOT working to the maximum limits for pressure and velocity AND that you are NOT loading full wadcutter bullets which are seated flush with the casemouth. Bear in mind that variations in the point of impact and group size may occur due to the difference in bullet shape. Shoot straight and reload safely!
 
#6 ·
A good manual will list what the loads were fired in...if it's a pressure gun or "real life" rifles...the barrel lengths and at least the groove diameter. Pressure gun tests are suually hihger than you really will get...pressure guns being built with pretty exacting tolerances.

If using "real life" guns, then deciding the upper load still has an element of guess work on the part of the technician running the tests. Can attache string-guage sensors and observe other factors, but it still boils doen to a gut feeing to "stop here".

Bith pressure gun and real life guns are not going to be the same as the gun in your hand...can be close, but are enough variables in manufacture that "identical" just isn't very likely.

Best seems to be to do your research. Check MULTIPLE manuals and compare...you aren't "shopping" for the fastest, in fact I'd tell you to toss out any that show data well off the average of all the manuals.
 
#7 ·
Good, solid advice -!

All firearms and chambers being slightly different, ALWAYS begin at the recommended start loads and work up in small increments for your individual firearm.

Manuals are representative - not chipped in stone. So many factors enter into the establishment of a cartridge loading (lot # of powder, brand and type of bullet, lot # of primer and type, case mfg'r and times of reloading, bullet seating depth, chamber size, actual bore diameter and length, temprature, humidity, atmospheric pressure) that the variables can be staggering. The manuals try to establish what the publisher feels is a safe range with all these combinations and will list accordingly.

Use the manuals for their intended purpose - a guide that will assist in developing safe loads.
 
#9 ·
Yes, the relaoding manuals sure do vary for all the reasons cited above. The one thing I've noticed that seems to be the biggest reason for descrepancy is the different guns and barrels used. Of all the manuals, the only one I have every truly shook my head at is the Lee Manual. Some of the loads and powder ranges I've come across in that one just don't seem advisable. For all the others I have used - Speer, Sierra, Hornady, Lyman (my favorite), Swift, Hodgdon) you will at least be in an acceptable range using any of them. As others have said, Start low and work up slowly. --Mykal
 
#10 ·
The loads in my older Speer manual tend to run hot. So, I largely use the data for possible powder choices knowing full well it's max is the may be too hot for some of my guns. But the difference is largely due to different barrels/chambers AND, most recently, lawyers.
Pressures in newer manual seem lower for some guns so as not to exceed factory pressures. Factory pressures in turn are based on SAAMI standards which are often quite low for chamberings that include old guns (e.g. 6.5 Swead, 7x57, 45-70 even the 30-06). That's why you may see two sets of figures in some manuals, one for older weaker guns and one for stronger ones.
The same laod parameters can be used for bullets of the same weight but different shape ..with caution. The issue is not so much the load as the kind of bullet and distance of the bullet to lands.
As for kind of bullet, monolithic bullets like Barnes X take more pressure to start squeezing down (obturate) into the barrel so they have to be back a bit more and use different load data than comperable jacketed lead bullets.
The shape of the tip (ogive) can mean a particular brand of bullet can be closer to the lands than a differnt brand of bullet of the same weight...even thought the overall length of the cardridge is the same. The one that is set closer will generally have higher pressure with the same powder charge, which may affect point of impact and accuracy. At max load levels it could even make that one too hot .
 
#11 ·
Cossack said:
The loads in my older Speer manual tend to run hot.
Yes, many of the old Speer manuals were published without the benefit of actual pressure testing. HOT HOT HOT!! Probably, the same is true of many of the reloading manuals produced in the 40s, 50s, and 60s by bullet companies. However the folks at Speer tended to really lean on the throttle. Some of the load data is downright scary.

Load data reduction over the years isn't all goodie-two-shoes type of political correctness; some of it was badly overdue!

I'd like to personally see some higher pressure loads for certain gun/cartridge combinations; on the other hand, we've never had it better. More powders, loads, and components than ever before. Within reason, we can reach performance levels with many cartridges that were downright dangerous 50 years ago.

Not meaning to pick on you; just do want to point out that there is old data that is good and old data that is well and truely dangerous.
 
#12 ·
With so many manuals now available for free on the web, there's no excuse to not have current data. I used to stick with the bullet company's books, figuring that they weren't trying to sell powders, and therefore included all the powders at proper amounts. Now, I do tend to go the various powder company sites for their scoop on charges. Check 'em out. They're very good.
 
#13 ·
I have found that the Lee data is the Lee data that comes on the card that comes with the dies. The card with the dies is Lee data that is esincially designed for folks using the Lee dipper method of measure. It is convienient for that purpose. In fact , I would have never found my favotite powder and load for the 44 mag if it had not been for the Lee Loader card.

what I am saying is the Lee data in some, but not all cases could be geared to this method of ease of measure instead of most accurate. They may not blow you up but they may not be exactly what you want. sure is some great data for easy loading on those cards though. I would think the 30-30 is one of those that has a lot of that card data in the manual. Alot of people use the "Little Lee Loader" and the dipper method to load that round.
 
#14 ·
I cross reference the Sierra and Nosler books and even though they have the same charges (sierra is a hair higher) for a lot of loads, however, all the Nosler bullets seem to add about 400 FPS to the load. :D

I'm speechless as the discrepancies, and that was the reason I came to shooters forum tonight, was to post a thread about this subject.

I'm not to worried, I weigh each charge by hand (yes, it takes forever to do 400 .357 Mag loads by hand) and I'm shooting a relatively tough pistol, a ruger GP100.
 
#15 ·
I can't even fathom weighing charges one at a time for 400 pistol loads, I don't have the patience for that. I used the scoops when I started reloading in the 70's, moved to a Lee powder measure a few years later and haven't seen a need to change anything since. My goal isn't top velocity, it's accuracy and consistency, if the best load is also fast that's just a bonus. I load on a Lee Turret press, 300-500 rounds at a sitting, using it single stage. It can get tedious, but the result is VERY consistent ammo, that over time has made me a better shooter, by removing as many variables as possible. Now when something goes south, I know it's me or the gun having a bad day, because it sure isn't the ammo. And truth be told, my guns don't have bad days. That leaves...........ah well, never said I was perfect. If I'm supposed to have good days, I guess that means I'm also supposed to have bad days, too! But as a wise friend of mine says, "If you woke up, today is already a good day!" :p

Papajohn the Prophetic Jokester
 
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