advice on max loads needed

ccook905

ccook905

Member
Rating - 100%
27   0   0
Location
Niagara Region, Ontario
I'm loading some 70gr speer semi spitzers with blc-2 powder into .223 and ran into some interesting load data.
Speer manual gives the following for min/max loads
start - 21.5 max - 23.5

Now on hodgdon site
start - 24.5 max - 26.5

Both show same coal of 2.140

Where do I start? 23.5? and move up looking for pressure signs?
Is reloading manual data dropping charge weights too much on conservative side?
 
The max load is rarely the most accurate.Start at 22 grains and increase by .5 grains for every new shot string.Look for pressure signs at all times.Say 23.5 grains looks good and 24 opens up and 24.5 covers a sheet of plywood,go back to 23.5 and work from there. By the way,col is not a good thing to go by unless for a semi or something finicky. Seat your slugs 30 thou off the lands or 10 thou off the max length of you mag.3 shots for every string so that you dont waste components.
 
Is the hodgdon site listing Speer bullets? Some bullets of the same weight have differing amount of bearing surface or the shape causes the base to sit deeper in the case at the same COAL and this can all affect load data.
 
The thing about loads in manuals, is that the people printing the manuals use different firearms, with different batches of components, and even different components. If one manual is based on a rifle with a larger chamber, and a slow batch of powder, the max load in that manual could contain significantly more powder, than the max load listed in a manual where the rifle used for testing , had a tighter chamber, and used a faster lot of powder. As well, different cartridge cases have different internal volumes, and bullets have different bearing surfaces. As for the COL listed in manuals, I choose to ignore them , and instead base the COL that I use, on my rifle.
 
Im loading for my HK sl8, semi so case oal length im limited to 2.250 due to mags. Hodgdon website lists load data for speer bullets, same bullet im loading for. I believe speer and hodgdon are owned by the same company which is why I could not understand the variance in the load data. I will be developing the load for the rifle and work it up, just really find it strange to have such a difference.
 
icehunter121 said:
The max load is rarely the most accurate.Start at 22 grains and increase by .5 grains for every new shot string.Look for pressure signs at all times.Say 23.5 grains looks good and 24 opens up and 24.5 covers a sheet of plywood,go back to 23.5 and work from there. By the way,col is not a good thing to go by unless for a semi or something finicky. Seat your slugs 30 thou off the lands or 10 thou off the max length of you mag.3 shots for every string so that you dont waste components.
Click to expand...

I agree with all of this except I would shoot 4 or 5 shot groups if I wasn't shooting well or shooting a new gun. Many loads in my Hornady manual max out where the Hodgdons site starts. Hodgdon does seem to have a fair amount of hot loads. Given the info you have there I would start at 22gr and work up to 26.5 in .5gr increments.

It's nice to know it's not just me who gets frustrated with inconsistant load data. That combined with the warning "NEVER EXCEED MAX LOADS". Gives me an ulcer!

Edit: I just checked my Speers manual. If you check you will see that the Vel they get with their max load is also well under the Vel of the start load on the Hodgdon site. It seems they just didn't want to find the full potential of that load. I have found that Alliant powder and Speers bullets seem to be in bed with each other. IE they tend to show the hiest velocities with Alliant powder (at least fot the callibres that I load). Also Alliant powders manual shows loads for mainly Speers bullets.

George
 
Last edited:
Im loading for my HK sl8, semi so case oal length im limited to 2.250 due to mags. Hodgdon website lists load data for speer bullets, same bullet im loading for. I believe speer and hodgdon are owned by the same company which is why I could not understand the variance in the load data. I will be developing the load for the rifle and work it up, just really find it strange to have such a difference.
Click to expand...

You can load for two rifles of the same make and model, using the exact same components, and one may produce more velocity and pressure with the exact same load. You can also load for the same gun, using the same components, but have powder from two different lots, and have significant differences in velocity and pressure. That is why the loading manuals so often vary.
 
stubblejumper said:
The thing about loads in manuals, is that the people printing the manuals use different firearms, with different batches of components, and even different components. If one manual is based on a rifle with a larger chamber, and a slow batch of powder, the max load in that manual could contain significantly more powder, than the max load listed in a manual where the rifle used for testing , had a tighter chamber, and used a faster lot of powder. As well, different cartridge cases have different internal volumes, and bullets have different bearing surfaces. As for the COL listed in manuals, I choose to ignore them , and instead base the COL that I use, on my rifle.
Click to expand...

X2

every loading manual beats it into your head that rifles differ, and that there is no reason to expect your rifle to tolerate the loads they found to be max with their rifle. Buy a chronograph, and if your velocities are exceeding published max velocities you might want to back off a little, but for the most part, if you are getting good brass life in your rifle with any load, you are probably well within safe levels. This is why you have to work up, to see what your brass is doing with lighter loads. With all the variables achieving the best load is a mixture of art and science.
 
I always try to cross reference at least 3 manuals. I also use a chronograph! If I am really not sure or want to be quick I only load one round each in 1 grain (.5g in small cases like 223) increments and fire them over the chronograph. This gets me into the velocity range I want to be at quickly without wasting bullets and powder. Once I figure what kind of powder charge I will need to get me mid to top velocity I will load up a few rounds at those charge weights and look for accuracy. I used to waste a lot of time building 3 rounds at each charge weight only to find they were WAY to slow or WAY to fast/too much pressure.
 
You must log in or register to reply here.
Back
Top Bottom