How the hell is loading data so different between manuals? [Archive] - Glock Talk

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wrx04
01-05-2012, 15:21
Im looking to load up some 200gr FMJ flatpoint ammo for the first time. I pull out the Lyman (49th) and get a load from 4.0 to 6.5 of unique. When i look in the speer book (#14), i get data between 6.5 and 7.3 of unique.

How the hell is the "start charge" of one the same as the "max charge" of the other?! I was planning on a 6.0gr charge to start, but just want to make sure i dont blow my hand off. :supergrin:

Thanks!

Colorado4Wheel
01-05-2012, 15:28
Unique is perfect. Your reading the manual wrong.

fredj338
01-05-2012, 15:32
Look harder. Every manual uses diff components & test platforms to work up data. Yes, bullets matter, yes case volume matters, yes primer brand can matter. Certainly test platforms matter. Universal test bbls are often min spec & service pistols more generous dims. So what you get is a wide variation in data. It's why I recommend using 3 diff published osurces & averaging data for start & max. Never exceed max average data unless working up carefully & learning how to read pressure signs.

MinervaDoe
01-05-2012, 15:37
My Hornady manuals are super conservative and my Speer manual is super aggressive. It's always confusing to compare the two. I've found a few Hornady loads which didn't cycle my automatics, but I do prefer to start off with their more conservative loads.
As said above, sometimes their equipment varies, or sometimes their lawyers have them print conservative data.

Colorado4Wheel
01-05-2012, 15:47
It couldn't possibly be that the powder has just varied over the years. Nay, that is just to easy of a explanation. It is nearly a million years old after all.

EL_NinO619
01-05-2012, 15:55
More paranoid Lawyers.... Nah what Fred said..

Zombie Steve
01-05-2012, 15:58
Unique is perfect. Your reading the manual wrong.

It couldn't possibly be that the powder has just varied over the years. Nay, that is just to easy of a explanation. It is nearly a million years old after all.

He's finally coming around!!!

GioaJack
01-05-2012, 15:58
None of the manuals know what they're talking about. Just fill a case with what ever powder you have on hand, hammer a bullet on and head to the range.

Oh, don't forget to switch on the video camera before firing. :whistling:


Jack

wrx04
01-05-2012, 15:59
Lyman 49th edition: 200gr jacketed hp (tested in 5" barrel)
Unique-----4.0 (starting charge) 604fps 7,300 C.U.P.
6.5 (max charge) 927fps 17,700 C.U.P.

*This isnt the exact bullet im using, but pretty darn close. The print does say that their data "MAKES FOR A GOOD MID-RANGE PRACTICE LOAD". Maybe this is why the data is lower than the speer:dunno:



Speer Reloading Manual #14: 200gr TMJ FN (tested in 4.4" barrel)
Unique-----6.5 (start charge) 860fps
7.3 (max charge) 984fps

So Fred, i guess you are right when looking at the fine print. The Lyman gives a pretty anemic starting point at only 600fps out of a 5" barrel (and they admit their data is only for mid-range plinking ammo)

The 7.3gr max charge from speer is also out of a shorter barrel, which produces a similar velocity as Lymans "max" out of a 5".

I think ill start out at 6.0gr and go from there, as i shoot a full size 1911.

MoneyMaker
01-05-2012, 16:29
If you look real close,they use different makers bullets,different seating depths,Go buy the book for what bullet you want to load,if they dont list it then call them as most times they can give you the correct info

TX expat
01-05-2012, 16:32
None of the manuals know what they're talking about. Just fill a case with what ever powder you have on hand, hammer a bullet on and head to the range.

Oh, don't forget to switch on the video camera before firing. :whistling:


Jack

Why fill a case when you could go ahead and do all thousand of 'em! :supergrin:

Batesmotel
01-05-2012, 16:32
Age of the manuals maters also. I use a lot of IMR-4064. A few years ago they changed the machine that makes it and the burn rate changed slightly. The next edition of the manual reflected that.

ron59
01-05-2012, 19:02
Yeah, I'd say that the seating depth is making the difference in the amount of powder. You seat deeper, there's less case capacity, you need less powder.

dbarry
01-05-2012, 19:06
Oh, don't forget to switch on the video camera before firing...
Jack

...and to blame it on lead bullets and polygonal rifling

teweekley
01-05-2012, 20:05
I find those books at Cabelas are handy - the colored ones that have load data for just one caliber. $7 for each isn't bad and they have load data from most bullet and powder manufacturers. Easiest way to compare data.

ponders
01-13-2012, 21:02
Why fill a case when you could go ahead and do all thousand of 'em! :supergrin:


i see im still catching crap for my epic thread:faint:

Colorado4Wheel
01-13-2012, 23:52
To us it was a lot of fun. What have you been doing lately?

shotgunred
01-13-2012, 23:57
Six months from now it will be you laughing at the new newb for doing the same thing.

njl
01-14-2012, 19:30
Dealing with the malfunctioning priming system on my RL550B today, I double-charged a 45acp with 8.8gr WST. I immediately realized what I'd done, and dumped it back in the hopper...but that wouldn't have been pretty with a 230gr Zero JHP. It didn't even quite fill the case.

MinervaDoe
01-14-2012, 19:35
I double-charged a 45acp with 8.8gr WST..... It didn't even quite fill the case.

:wow: That's the problem with those "econimical" powders.