Large discrepancies between loading manuals. [Archive] - Glock Talk

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atakawow
04-29-2011, 16:51
ABC:

9mm 125gr LRN 3.9 - 4.2gr Bullseye.

Lee:

9mm 125gr LRN 4.7 -4.9gr Bullseye.
:dunno:

I have some old (a year?) 125gr LRN loaded with 4.8gr Bullseye and wondering if they are safe to shoot?

Boxerglocker
04-29-2011, 17:07
Normally I would check the powder manufacture website too. However with Alliant's is a little different. You'll need to give them a call for an actual range.
Otherwise, if starting from scratch... I would take the lower range and work up from minimum. Alliant shows 4.7 for a 115 GDHP so with LRN I would definitely start in the 3.9 and work up.

SFCSMITH(RET)
04-29-2011, 17:15
Powder charge is only one component.. brass specified and primer used both can and will affect pressure, which is what manufacturers use to decide load data.

ron59
04-29-2011, 19:30
Powder charge is only one component.. brass specified and primer used both can and will affect pressure, which is what manufacturers use to decide load data.

And NO mention of OAL. Until now. :whistling:


A shorter OAL (with the same bullet profile) will make that recipe with less powder be just as "powerful" as a longer OAL and more powder.

fredj338
04-29-2011, 19:47
Powder charge is only one component.. brass specified and primer used both can and will affect pressure, which is what manufacturers use to decide load data.

AND, without OAL, the rest means little. The biggest pressure contributer in small vol/high pressure rounds is powder charge then OAL. A 4.8 charge of BE under a 124-125grLRN is going to be very very hot. Shoot them at your own risk.

PCJim
04-29-2011, 19:50
I'll second Fred's comment. I use 3.9gr BE under a 125gr LCN (COL 1.145) that runs an average 1030-1060fps out of my P226. It is comfortable, meets IDPA power requirements, and makes enough smoke to keep those blood-sucking 'skeeters somewhat at bay.

atakawow
04-29-2011, 21:53
Mine sits at around 1.120. The Lee book suggests 4.7 - 4.9 gr BE at 1.150.

I guess I got myself some mini explosives...

fredj338
04-30-2011, 09:50
Mine sits at around 1.120. The Lee book suggests 4.7 - 4.9 gr BE at 1.150.

I guess I got myself some mini explosives...

Lyman doesn't even get close to that for a 120grLRN. A charge of 4.9gr is even pushing max for a 124gr jacketed bullet. I would not but your gun/hand/eyes.:shocked:

GioaJack
04-30-2011, 11:27
You think there's big discrepancies in manuals now, pick up a manual from the '60's and '70's and compare them to new manuals.

It's like going from break dancing to ballet.


Jack

Three-Five-Seven
04-30-2011, 15:39
Different loading manuals have different teams of lawyers working for their company.

I find the Hornady manual particularly conservative. And, I find the Speer manual at the opposite end of the spectrum.

Of course the correct procedure is to use the most conservative data as your starting point and proceed with confidence as you work your way up.

noylj
04-30-2011, 22:31
This is why I compile all the loading data I have for a given caliber so I can start at the LOWEST starting load.
Bullet Weight Powder Weight Velocity Start/Max Power Factor COL
L-RN 125 Bullseye 3.3 946 Start 118
L-RN 121 Bullseye 3.4 939 Start 114
L-CFN 124 Bullseye 3.5 852 Start 106
Speer L-RN 125 Bullseye 3.5 929 Start 116 1.130
Lee 356-125-2R 126 Bullseye 3.5 936 118 1.160
L-RN 125 Bullseye 3.5 990 Max 124
L-CFP 121 Bullseye 3.7 950 Start 115
L-RN 121 Bullseye 3.7 990 Start 120
Speer L-RN 125 Bullseye 3.8 962 Max 120 1.130
RCBS 9mm-125-RN 123 Bullseye 3.8 1037 128
L-RN 125 Bullseye 3.8 1040 Start 130
L-CFN 124 Bullseye 4.0 987 Max 122
Hdy L-RN 124 Bullseye 4.1 1025 Start 127
Hdy L-RN 124 Bullseye 4.2 1050 130
L-RN 125 Bullseye 4.2 1067 Max 133 1.016
L-RN 121 Bullseye 4.2 1175 Max 142
Lead 125 Bullseye 4.3 Max 0
Lead 125 Bullseye 4.4 Start 0
Hdy L-RN 124 Bullseye 4.4 1075 Max 133
L-RN 121 Bullseye 4.4 1115 Max 135
L-CFP 121 Bullseye 4.4 1125 Max 136
Lyman 356402 120 Bullseye 4.5 1085 130
Lead 125 Bullseye 4.9 1165 Max 146 1.150
Lyman 356402 120 Bullseye 5.0 1210 145

That is over 30 years of data from manuals I have purchased. A warm, comforting feeling--isn't it.
3.5-4.2gn works for me, with a max at 4.5gn.