Loading over max

[krprice84]

So I loaded above max. No pressure signs on case. But it's shooting 225 fps faster than quick loads prediction.

Did you measure fired water capacity of the cases? Did you get the bullet seating depth right?

Also, did you find out what quickload would predict for a load you have already chrono'd?

What I do is chrono a load (average five of them) and then go to quickload, make sure the water capacity, trim length (it affects the capacity because quickload uses it to determine how much the bullet protrudes into the case), bullet shank seating depth, etc, and then I'll put in the powder charge. Don't forget to charge the start pressure. If you are seated at the lands, I use around 8k-9k, in the lands I use 10325, off the lands ten thou i use about 6k and off more about 4k. Add a couple k if you are using a Magnum primer but this one is certainly a swag. Now see what quickload says you should have gotten, check the powder temperature and make sure you set it at what the temp was outside, or a little below that if the cases were on the shade before firing. If it doesn't match up, you can play with the burn rate of the powder, shouldn't have to adjust it more than about ten percent. Also make sure you double check the weighting factor. I think that if you go to a section on case dimensions it will give you a recommended weighting factor and that doesn't always match up to the default value.

You should be able to get the velocity right on.

Now use those variables and see what it says for the predicted velocity at your over max charge. You can then use that burn rate as a better baseline for that batch of powder, even on other cases/cartridges

 

[ReloaderRick]

Did you measure fired water capacity of the cases? Did you get the bullet seating depth right?

Also, did you find out what quickload would predict for a load you have already chrono'd?

What I do is chrono a load (average five of them) and then go to quickload, make sure the water capacity, trim length (it affects the capacity because quickload uses it to determine how much the bullet protrudes into the case), bullet shank seating depth, etc, and then I'll put in the powder charge. Don't forget to charge the start pressure. If you are seated at the lands, I use around 8k-9k, in the lands I use 10325, off the lands ten thou i use about 6k and off more about 4k. Add a couple k if you are using a Magnum primer but this one is certainly a swag. Now see what quickload says you should have gotten, check the powder temperature and make sure you set it at what the temp was outside, or a little below that if the cases were on the shade before firing. If it doesn't match up, you can play with the burn rate of the powder, shouldn't have to adjust it more than about ten percent. Also make sure you double check the weighting factor. I think that if you go to a section on case dimensions it will give you a recommended weighting factor and that doesn't always match up to the default value.

You should be able to get the velocity right on.

Now use those variables and see what it says for the predicted velocity at your over max charge. You can then use that burn rate as a better baseline for that batch of powder, even on other cases/cartridges

Thanks. All measurements are correct. Chronographed other loads and they are pretty close to predicted velocities. I'm off the lands about 15 thou. Using a match primer. If I adjust my burn rate to match the velocities the pressures are over max. It grouped very good and ES was good also. Case had no signs of pressure.

 

[krprice84]

Thanks. All measurements are correct. Chronographed other loads and they are pretty close to predicted velocities. I'm off the lands about 15 thou. Using a match primer. If I adjust my burn rate to match the velocities the pressures are over max. It grouped very good and ES was good also. Case had no signs of pressure.

Interesting.

What chrono were/are you using? How consistent from day to day is that load? Can I ask what it is and what velocity you get?

I'm wondering if you really are a bit over pressure, you don't always get signs when you get to saami spec. I was just talking to a guy who regularly pushes his gun 2-300 fps over the normal max velocity for that bullet, with zero pressure signs. He does that because there's no pressure signs, and he's able to hit the next optimal barrel time/velocity node.....So why not. I'm going to be working up a load for a 55 grain bullet soon here and see if I can't get it up to the next node (about 3450 fps if i recall right....Right now it's at about 3250 I think).

Also what are conditions like where you are measuring (sunlight etc)? When you say other loads were close, was it with the same powder, just different bullet/different cartridge? Or was it different powder in the same cartridge /under the same bullet?

I'm really curious what's going on cuz for me, it has always been pretty close, and when it hadn't, I could tweak it close and use that tweaked data for other loads

 

[rookie wildcat]

Not all guns, or brass for that matter, will react the same to a given charge. Your best bet is to start well below max and work your way up, watching for pressure signs as you go. One thing you will likely find, though, is that as your loads get hotter and hotter, accuracy will fall off. I'm not an authority by any means, but in all my guns, including black powder, my most accurate loads tend to be around the mid-point of suggested loads. With modern bullets being what they are, you're better off getting a bullet that will perform well at your optimum velocity, rather than trying to squeeze every last fps out of a bullet.

You just aren't progressing to the next node of barrel time/velocity. Every load I build has at least 3 "accuracy" nodes. I usually settle on one for reduced charges and my hunting loads are always max published loads or better.

Funny, my rifles tend to shoot best at maximum or very near. If a load only shoots at the bottom end I'll scrap it and start over looking for a max/near max load that shoots. High pressure tends to give tighter spreads, and at distance starts making a big difference. Also hotter loads are less prone to going to crap everytime the sun goes behind a cloud.

I have left "distance" behind. I have no hesitation shooting animals out to 400yds, but my 600yd deer are a thing of the past, even if I can ring an 8" gong at 500yds 8 out of 10 times. That being said, I remain a "one powder fits all" man, so I will never wring out the best velocity in an'06, never own a magnum, but, man, can those .223s fly!

 

[ReloaderRick]

First time shooting this load over chrony. Other loads (same powder) were close in velocity to QL predictions. Using a shooting chrony, sun was just coming up behind me. .243 87 gr hornady SP. Average velocity was 3306.

 

[BigUglyMan]

I'm the old timer you're looking for!
When Jack O'Connor figured the famous load of surplus H4831, then called, "4350 data powder," of 60 grains of the surplus powder in a 270 behind a 130 grain bullet, we all jumped on it. Jack didn't say to start out light, so we just managed to get 60 grains of the coarse powder into a case and forced a 130 grain bullet into the case and shot them. I also scooped the powder out of 50 pound kegs into paper bags and amazingly, I still have a couple of pounds of the original powder, once called 4350 data powder.
A lot of years later I chronographed the load and found my 270 gave the bullet just a little under 3100 fps, like Jack said it would go!
When Hodgdon's ran out of the original surplus powder and either made, or had made for them, a new version of it they stated that the same loading data could be used for the new, as was used for the old.
In August of 1991 I got around to checking the two powders. I loaded ten 270 cases with the same primers and bullets, five loaded with the old surplus powder and five loaded with the new Hodgdon's canister powder and shot them over a Oehler chronograph. Here are the results.

Those with surplus powder, average 3078 with a es of 33.
Those with the new powder, average 2960 with an es of 45.

Within the last 3 or 4 years I ran the same powder test, old surplus and new H4831, using a 243. The results were very similar to the old test shown above, but I can't, right now, find the printed results.

Now I'm confused. You're old and you're H4831. Does that really mean that you are actually 4350?

 

[Papaclaude]

You just aren't progressing to the next node of barrel time/velocity. Every load I build has at least 3 "accuracy" nodes. I usually settle on one for reduced charges and my hunting loads are always max published loads or better.

I have left "distance" behind. I have no hesitation shooting animals out to 400yds, but my 600yd deer are a thing of the past, even if I can ring an 8" gong at 500yds 8 out of 10 times. That being said, I remain a "one powder fits all" man, so I will never wring out the best velocity in an'06, never own a magnum, but, man, can those .223s fly!

I have nowhere near the knowledge or experience to challenge you on that. So do you go beyond signs of pressure, or is the hunting node below pressure signs? You have truly piqued my interest, as I have been working from my experience baseline that mid-line is best. thanx for the info.

 

[bigedp51]

So I loaded above max. No pressure signs on case. But it's shooting 225 fps faster than quick loads prediction.

Quickload output data are ball park guesstimates, in order for Quickload to give accurate readings you need a chronograph. Once you get your chronograph velocity you change the powder burn rate in Quickload until the velocities match. (plus other tweaking)

In other words Quickload must be calibrated for each firearm and load, meaning without a chronograph Quickload is nothing more than a computer generated guess.

Quickload Reloading Software
http://www.accurateshooter.com/gear-reviews/test-quickload-review/

Optimal Barrel Time Concept
http://www.the-long-family.com/optimal%20barrel%20time.htm

QuickLOAD calibration -- can you get it to match multiple bullet weights?
http://forum.accurateshooter.com/index.php?topic=3746714.0

 

[ReloaderRick]

I may have figured it out. Got the donught happening. Maby increasing pressure. And velocity.