interesting information on the hodgdon website.

[SHARPSHOOTER]

I was getting a 223 load for my precision poodle shooter from the hodgdon website using 75 grain bullets and benchmark powder. As I was looking at the data I noticed in their cartridge information that they show a 1:12 " twist in their test gun. They surely could not have gotten any type of decent accuracy using a 1:12" twist.

Here is the info as I pulled it from the website.




Hodgdon Powder Company
Cartridge Load Recipe Report - 7/27/2007
data.hodgdon.com 223 Remington
Load Type: Rifle Powder: Benchmark
BW: 75

Cartridge Information
Case: Winchester Barrel Length: 24"
Twist: 1:12" Trim Length: 1.750"
Primer: WINCHESTER SR

223 Remington
Cartridge Load Data Starting Loads
________________________________________ Maximum Loads
________________________________________
Bullet Weight (Gr.) Powder Bullet Diam. C.O.L. Grs. Vel. (ft/s) Pressure Grs. Vel. (ft/s) Pressure
75 GR. JLK VLD Benchmark .224" 2.250" 21.5 2610 41,900 CUP 23.5 2829 49,400 CUP

NEVER EXCEED MAXIMUM LOADS

[kerplode]

Unless it's for a factory load, I doubt they care much about accuracy when they're developing loading data. They're going to concentrate on pressure and velocity in order to come up with a reasonable minimum and maximum charge weight for the powder/bullet combination under test. Finding the specific charge from within their published safe range that is most accurate in a particular firearm is the reloader's job.

[mj2evans]

Would a 1:8 to 1:7 barrel vs. 1:12 change pressure any? I am pretty sure my 24.0g RL15 and Hornady match 75g in a 1:8 barrel is fine but what if you are trying to push the limit of a reload?

[hagar]

Originally posted by mj2evans
Would a 1:8 to 1:7 barrel vs. 1:12 change pressure any? I am pretty sure my 24.0g RL15 and Hornady match 75g in a 1:8 barrel is fine but what if you are trying to push the limit of a reload?

I shoot 24.5 grains of RL15 with the 75 Hornady in a 1 in 7 twist AR15 with no signs of pressure. Supposedly the tighter the twist, the higher the pressure, but I see no difference between my 1 in 8 and 1 in 7 twist uppers.

[SHARPSHOOTER]

from what I understand the 1 in 8 is actually supposed to be a 1 in 7.5 or least that is what I was told by a couple of people. So there would be very little difference between the two in reality.

What I was saying earlier is that most reloading manuals I own usually have the most accurate load tested notation in them. This information from the Hodgdon website would make it impossible to do any accuracy testing.

Also the assertion that the most accurate load is the one with the most velocity is a conditional statement at best and is not a definitive truth. A lot of times it does hold true but I have observed more than one occassion when it was not the max load that delivered the best accuracy.

[Brush511]

I doubt if that data was fired for accuracy. A 1 in 12 barrel shouldn't stabilize a 75gr bullet worth a hoot. In some reloading data, they list "potentially most accurate load" or "potentially most accurate powder". I think in those cases they use the lowest standard deviation from chronograph results and not actual group size. Your rifle may not like their "most accurate load" anyway. Rifles seem to have individual tastes.

As far as the highest velocity giving the best accuracy, I've had mixed results with my rifles (I reload for 15 different rifle calibers and more than one rifle in some calibers). It seems like a little more than half of my rifles prefer loads slighty under max to max loads.