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igojuone

igojuone

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Looking at load data and for Hornady 165 gr. GMX I'm getting different numbers from my Hornady handbook and the Hodgdon web site. Hornady says H4350 starting load 48 gr. and max 58.9(in the red) while Hodgdon starts at 51 gr. and max at 55.4 gr. I understand I'll need to keep an eye out for over-pressure no matter which data I follow but which should I follow?

The 2 also suggest different COL Hornady being 3.210" and Hodgdon is at 3.225"
 
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For the 30-06?
I was shooting 57gr of h4350. That is what was in my hornady book so that is what I went with. Didn't even know that hodgdon had data for that bullet for 30-06 lol. Was also shooting 57gr for sst, partitions, and any other 165gr in the 30-06
 
I like to use the powder manufacturer data as a starting reference, but the gun I'm shooting is going to decide where the max load falls
 
Thanks again everyone, it all seems pretty common-sense but safety is everything so I started out with 51 gr. and did some at 52, 53 and 54 and will re-evaluate from there. Max from the Hodgdon site is 55.4
 
I look through my 3-4 manuals and try to find a happy medium but still start on the low side till I see what the guns does accuracy wise..
 
I shoot for accuracy and have a low node and high node with my guns. I made dope charts for both. I will re-do/check my data again in 300rds or so
 
I like to take the info from the bullet manufacturer. I know people say that a 150gr 30 caliber bullet is a 150gr 30 caliber bullet but I find it hard to believe that a 150 SGK will generate the same pressure as a 150 NPT because I've seen that very bullet substitution (NPT substituted in a load developed for SGK) create self-depriming overpressure situations.
 
bcsteve said:
Does Hodgdon specify for the Hornady GMX? Monometal bullets usually take pressure differently.
Click to expand...

They say to use conventional data....if you look at Barnes data vs Hodgdon for example, you usually see Barnes with heavier charges listed. You need to work up loads for your rifle regardless of the listed maxes.
GMX
Features:
Streamlined design for ultra-flat trajectories
Devastating terminal performance across a wide range of velocities
Copper alloy construction and double cannelures reduce fouling
Compatible with conventional reloading data
California Compatible
 
BigUglyMan said:
I like to take the info from the bullet manufacturer. I know people say that a 150gr 30 caliber bullet is a 150gr 30 caliber bullet but I find it hard to believe that a 150 SGK will generate the same pressure as a 150 NPT because I've seen that very bullet substitution (NPT substituted in a load developed for SGK) create self-depriming overpressure situations.
Click to expand...
Whoever did that was dangerously irresponsible.

A 150gr .308 is a 150gr .308 from starting loads, with proper load development. Swapping the bullet on an already developed load is not something I or any reloader I know would do. Swap the bullet, start development all over again. They are just considered the "same" bullet for starting load purposes.
 
LUTNIT said:
Whoever did that was dangerously irresponsible.

A 150gr .308 is a 150gr .308 from starting loads, with proper load development. Swapping the bullet on an already developed load is not something I or any reloader I know would do. Swap the bullet, start development all over again. They are just considered the "same" bullet for starting load purposes.
Click to expand...

I know that. It was a bad #### up but fortunately there are different levels of ####ups. There are #### ups that blow the extractor off a Sako and there are #### ups that blow an action apart. Fortunately this was the former. Little #### ups are God's way of tapping you on the shoulder to make sure you're listening. Best is to listen lest God decides he needs something more strong to get your attention.
 
From Quickload, using the SAAMI max overall length of the 30-06 of 3.34"

And to compare results with a flat based lead core Interlock, loaded to the same chamber pressure. Note difference in charge weight

Code: 
Cartridge          : .30-06 Springfield
Bullet             : .308, 165, Hornady GMX 30470
Useable Case Capaci: 59.082 grain H2O = 3.836 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H4350

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-10.0   95    50.40   2580    2440   46941   7980     93.3    1.234
-09.0   96    50.96   2607    2490   48282   8073     93.8    1.221
-08.0   97    51.52   2633    2541   49668   8165     94.2    1.207
-07.0   98    52.08   2660    2592   51102   8255     94.6    1.194
-06.0   99    52.64   2687    2644   52582   8343     95.0    1.181
-05.0  100    53.20   2713    2697   54110   8428     95.4    1.167
-04.0  101    53.76   2740    2750   55684   8512     95.7    1.154  ! Near Maximum !
-03.0  102    54.32   2767    2804   57306   8594     96.1    1.142  ! Near Maximum !
-02.0  103    54.88   2793    2858   58978   8673     96.4    1.129  ! Near Maximum !
-01.0  104    55.44   2820    2913   60701   8751     96.8    1.116  ! Near Maximum !
+00.0  105    56.00   2847    2969   62477   8825     97.1    1.104  ! Near Maximum !

165gr SP

Code: 
Cartridge          : .30-06 Springfield
Bullet             : .308, 165, Hornady SP 3040
Useable Case Capaci: 62.434 grain H2O = 4.054 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H4350

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-10.0   96    54.27   2642    2557   44936   8707     93.9    1.272
-09.0   97    54.87   2671    2614   46439   8808     94.4    1.254
-08.0   99    55.48   2700    2670   47994   8908     94.8    1.235
-07.0  100    56.08   2729    2728   49595   9004     95.3    1.217
-06.0  101    56.68   2757    2786   51246   9098     95.7    1.199
-05.0  102    57.29   2786    2844   52948   9189     96.1    1.182
-04.0  103    57.89   2815    2903   54709   9277     96.5    1.165  ! Near Maximum !
-03.0  104    58.49   2844    2963   56531   9362     96.8    1.148  ! Near Maximum !
-02.0  105    59.09   2873    3023   58418   9444     97.2    1.131  ! Near Maximum !
-01.0  106    59.70   2901    3084   60371   9523     97.5    1.115  ! Near Maximum !
+00.0  107    60.30   2930    3146   62394   9599     97.8    1.099  ! Near Maximum !
 
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BigUglyMan said:
I know that. It was a bad #### up but fortunately there are different levels of ####ups. There are #### ups that blow the extractor off a Sako and there are #### ups that blow an action apart. Fortunately this was the former. Little #### ups are God's way of tapping you on the shoulder to make sure you're listening. Best is to listen lest God decides he needs something more strong to get your attention.
Click to expand...

Quickload suggests only a 2,000psi increase in pressure when switching from a 150gr Sierra BTSP to a 150gr Nosler Partition. Maybe you left the can of Bluedot on the loading bench? ;)
 
todbartell said:
Quickload suggests only a 2,000psi increase in pressure when switching from a 150gr Sierra BTSP to a 150gr Nosler Partition. Maybe you left the can of Bluedot on the loading bench? ;)
Click to expand...

Nope, I think that would have made a bigger boom. Not sure why it did what it did, but it did it.

And just to be fair, it wasn't me, it was the old Man who had, at the time, about 40 years of experience reloading.
 
Sounds like he was way over to begin with and then substituted bullets. .30-06 has a large safety margin already being loaded to 55-58k. Pretty sure it takes 70k+ to cause anything close to that. Just substituting bullets with a normal load would not cause pressure to rise that much
 
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