QuickLOAD Max Charge

[kumaichi]

I recently purchased the QuickLOAD application and have a question about the max charge. I was wondering if I could get some thoughts from experienced handloaders.

Rifle:
700 Winchester 5R w/24" barrel

Components:
.308 Winchester (Hornady Brass)
Federal 210 (Not Magnum) Primers
VV N550 Powder
Sierra 175gr HPBT MatchKing

QuickLOAD Settings:
Cartridge Length = 2.954
Case Length = 1.999
Max Case Capacity = 56.20
Useable Case Capacity = 51.335

From what I can gather, the QuickLOAD "ideal" is to get the Barrel Time (BT) to match one of the nodes in the Optimal Barrel Time (OBT) chart. The closest I can get to a OBT is 1.230 which lines up pretty closely with Node 5 in the chart. In order to get to that OBT, it requires 49.32gr of powder. The VV manual says the max charge is 45.8gr. That to me seems like a really huge gap.

I still need to go and match up my muzzle velocity with QuickLOAD but I couldn't resist playing with QuickLOAD.

I guess the basic question I have is, am I going to blow myself up with this line of thinking?

My QuickLOAD .dat file can be found here.

Thanks

Craig

 

[rick2800]

Re: QuickLOAD Max Charge

i just started using quickload also never even noticed that where is the node chart?

 

[kumaichi]

Re: QuickLOAD Max Charge

I found the OBT chart in this SH thread http://www.snipershide.com/forum/ubbthre...rue#Post2122173

That thread is what got me started down this OBT path.

 

[DocB]

Re: QuickLOAD Max Charge

craig_m,

QL calculates two barrel times, one from 10% PMAX and one for total barrel time. Compare the one which shows up on the graph to the calculated one. I prefer to use the one for total barrel time.

Your maximum case capacity seems low. Check a case fired in your rifle with the dead primer still in it, filled to over flowing.

QL has four zones. 0-75% of blow it up (white), 75-85%, (yellow), 85-100% (red), and above blow it up. I've usually found best accuracy at the border of the yellow/red zone, but that's just me. Search for threads on measuring case head diameters as a way of evaluating case pressures. You may wish to look at %burned and % case capacity as evaluation criteria, above 98% is good.

With the VV powders, I've found WLRs tend to work better than FGMM. YMMV. Work up to any load 0.5gr. increments and look for pressure signs, if you see brass deformation, stop and back off.

HTH,
DocB

 

[rick2800]

Re: QuickLOAD Max Charge

thanks i must have missed that

 

[kumaichi]

Re: QuickLOAD Max Charge

Hi DocB,

Thanks for your reply. I'll get a micrometer and start measuring for pressure signs. It looks like the parameters I have set in the .dat file meets the criteria you were speaking about. I guess I'll start at VV's max load and move up .5gr until I reach the QL parameters to see if there are any signes of excessive pressure. One question, what is WRL's?

Thanks,

Craig

 

[DocB]

Re: QuickLOAD Max Charge

craig,

WLRs are Winchester Large Rifle primers. Mind letting us know what you will look for with case head expansion, or if you were able to find out what to look for with case head expansion?

HTH,
DocB

 

[kumaichi]

Re: QuickLOAD Max Charge

DocB,

I found this article on measuring case head expansion, http://www.jamescalhoon.com/primers_and_pressure.php As the article says, I'll measure before firing and after. I don't have the blade type micrometer but I have the anvil type so I can measure the case head and should be good, right?

I also found another article saying that measuring the case head expansion isn't an indication of excessive pressures. It's a long thread http://www.24hourcampfire.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=19112

The interesting part is posted by Ken Howell, 7th post down from the top. So much conflicting information on this stuff.

Thanks for the primer suggestion, the Federal primers are sometimes hard to find.

Craig

 

[Fred_C_Dobbs]

Re: QuickLOAD Max Charge

Craig, something smells funny. I get 178-gr A-Maxes onto the fifth accuracy node with my 24" .308 using about three grains <span style="text-decoration: underline">under</span> the max published load for Varget. Just 1.2gr over Hodgdon's published max gets me to the <span style="text-decoration: underline">fourth</span> accuracy node, 1.102ms. I'd be flabbergasted if you needed anywhere close to four grains of N550 over VV's published max just to get to the <span style="text-decoration: underline">fifth</span> node.

So I see two possibilities. Either 1) VV's published max load is way the hell conservative, or 2) QL's data for N550 isn't accurate. Either way, I suspect you're going to have to tweak the hell out of your BRF to bring it in line with your range data. So QL's not going to be a lot of help choosing your initial OBT load. I always consider the first OBT range session just a tune-up for tweaking my BRF anyway but I think your case is worse than most.

I'd suggest you find out what load some other N550 users are shooting and start a little to the conservative side of them. There's nothing stopping you loading the hotter loads, too, but you don't have to shoot them all. I've always got bullets to pull after my initial OBT range session because I deliberately load up incrementally hotter test loads that I know are going to end up <span style="text-decoration: underline">too</span> hot, then I start shooting and checking for those adverse pressure signs and stop shooting when the symptoms reach my max comfort level.

 

[kumaichi]

Re: QuickLOAD Max Charge

Fred,

I think you're right, I've been looking at other powders through QL and they aren't anywhere near the amount or generate pressures like the VV N550 and have higher burn rate %.

I did a ladder test last weekend with the 168 and 175 SMK's. I loaded a bunch of rounds with those charges which ironically ended up being the max VV recommended loads. I'm going to chronograph those this weekend and adjust the BRF to get everything to match up in QL. Like you said, I can get a more reasonable starting point setting up QL to match my range data.

I'm also going to change the O.A.L. on half of the loaded rounds I have. Right now I have them set to 0.010 off the lands @ 2.954 (I used the Hornady O.A.L. measuring tool). I was looking at the Southwest Ammo .308 loads and they are getting 2600-2650fps seating them @ 2.815. According to QL, I would only get around 2500fps @ 2.815. Something is certainly fishy.

Thanks again for all your guys help with this, QL can certainly be confusing and intimidating,

Craig

 

[QRE23]

Re: QuickLOAD Max Charge

Also remember that if you are touching the lands, even if it's just barely touching, you have to increase your shot start pressure to 10,825PSI this is often missed and will change you inition pressure and often put you over pressure.

 

[kumaichi]

Re: QuickLOAD Max Charge

I remember reading something about that but wasn't sure what to do with it. I think to help alleviate another variable, I'll just seat them all at 2.815. Besides, @ 2.954 I have to feed them one at a time, kind of a pain for possibly no gain. I can play with seating depth once I get everything else working correctly.

Thanks for the reminder samson.

 

[The Mechanic]

Re: QuickLOAD Max Charge

I am getting 51K psi with that load. About 1K in the red so that would be pushing it. As others have said you should be starting much lower and checking for pressure. There is a whole lot of variable that can be loaded in QL. Enviro is something that needs to be accounted for along with accurate measurements of your brass after firing and lenght to the lands, etc.

 

[QRE23]

Re: QuickLOAD Max Charge

The default standard temp is 70degrees F. It you click the little hand with a pencil like thing in it that is just to the left of the powder selection chart it will make a thermometer like thing pop up. If you click the thermometer it will allow you to change your outside default temp to whatever you want then click apply. You will be very surprised how much it changes fps and pressure.

 

[kumaichi]

Re: QuickLOAD Max Charge

That's something I'll definitely need to do, the temperature can have some really crazy swings here from winter to summer temperatures. Thanks for the instructions, I've been reading about how QL will let you change the temperature but I couldn't find out how to change it. Much to learn about this application.

 

[QRE23]

Re: QuickLOAD Max Charge

Yes there is and you can reallllllllly screw things up too. I've accidently deleted the whole list of bullets, powders and cartriges and had to uninstall and reinstall multiple times.

But I never would have figured this stuff out had I not been tinkering around with things. LOL

 

[The Mechanic]

Re: QuickLOAD Max Charge

I printed out the entire manual at <span style="text-decoration: line-through">work</span> uhh I mean at home and the thing is a friggin' dictonary. I have spent a few hours just browsing it.

 

[kumaichi]

Re: QuickLOAD Max Charge

I printed it out as well, great for when you have trouble going to sleep at night, heh. I am however getting through it but it raises more questions than it answers. That's why I tried reaching out here and as I found out, there is a wealth of knowledge from the users here on SH.

Thanks again to everyone who's offered their time to help me out.

 

[QRE23]

Re: QuickLOAD Max Charge

Reading the directions/instructions gives me a serious headache and makes my eyes almost cross. lol

 

[The Mechanic]

Re: QuickLOAD Max Charge

The more you read it the more you find that there is so much information you can plug in or change. It will really make you pull out the measuring tools. I can see that by the time you actually get it sorted out you would already have a huge dope sheet you could go off of already.

 

[kumaichi]

Re: QuickLOAD Max Charge

Went shooting this weekend and found out the following:

Alt: 515ft
RH: 44
BP: 30.090
Temp: 51.1

.308 175gr SMK VV N550
45.5gr
1 - 2411 fps
2 - 2433 fps
3 - 2436 fps
4 - 2436 fps
5 - 2422 fps
-------------
Avg: 2428 fps

46.0gr
1 - Err
2 - 2486 fps
3 - 2471 fps
4 - 2456 fps
5 - 2466 fps
-------------
Avg: 2470 fps

46.5gr
1 - 2511 fps
2 - 2500 fps
3 - 2516 fps
4 - 2504 fps
5 - 2494 fps
-------------
Avg: 2505 fps

47.0gr
1 - 2559 fps
2 - 2549 fps
3 - 2540 fps
4 - 2548 fps
5 - 2563 fps
-------------
Avg: 2551 fps

47.5gr
1 - 2577 fps
2 - 2588 fps
3 - 2583 fps
4 - 2598 fps
5 - 2578 fps
-------------
Avg: 2585 fps

I plug in the temp and weight of the charges and for each charge, I have to change the Ba so it will match the data I actually compiled. I thought you could change the Ba to match up with one load and the rest would fall into place. My goal was to get between 2600-2650fps and with the temperature set, I can get that range up to around 90 degrees. I'm also going to run the Federal Gold Medal Match through the chronograph and see what I get.

Am I still doing something wrong?

Craig

 

[DocB]

Re: QuickLOAD Max Charge

craig,

Got a picture of the 47.5 primers?

Thanks,
DocB

 

[justinbaker]

Re: QuickLOAD Max Charge

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: craig_m</div><div class="ubbcode-body">
I plug in the temp and weight of the charges and for each charge, I have to change the Ba so it will match the data I actually compiled. I thought you could change the Ba to match up with one load and the rest would fall into place. My goal was to get between 2600-2650fps and with the temperature set, I can get that range up to around 90 degrees. I'm also going to run the Federal Gold Medal Match through the chronograph and see what I get.

Am I still doing something wrong?

Craig </div></div>

craig, to get QL to match many of the charges you need to change more than just the burning rate. here is a quote from Chris Long on another site describing what he changes

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">hought that I'd jump in here and let you all know what I usually do to tweak QL to match range data. First, I have an older paper on this general process posted here:

http://www.the-long-family.com/Tuning%20QL%20to%20achieve%20best%20results.pdf

I have been improving this process, and hope to be able to update that paper eventually. Currently, my three main "tweaks" in QL are:

1.) Burn rate - no more than 5% higher or lower. More than that and I go to #2
2.) Weighting factor - no more than 10% change from QL default, else go to #3
3.) Bullet weight - this is a very good way to compensate for bore friction and other physical things that QL can't model. An increase in friction effectively reduces the accelerating force on the bullet, slowing it down. Increasing the bullet mass does the same thing in QL (F=MA). If you have to tweak this by more than a few single digit percentages, then there is something very weird going on. If things get too weird, reset it all to QL defaults, and start over with just the bullet weight and see what you get. I had one Savage 6mm barrel on a friends rifle that was really rough, and required a 3 grain increase in bullet weight (from 105 grains) to get the velocities to match. It was the only tweak that would let the model even get close to the right predictions.

The process is trial-and-error, tweaking these parameters until you can match at least two velocity measurements. I usually fire at least three different charge weights, from low to high, trying to bracket the expected OBT velocity range(s), and record velocity for each trial. It is best to fire 5 shots at each weight, if you have the patience, as the velocity average will be much more accurate than a single shot value. Single shots are OK to get you in the ballpark, but to get a good QL model, you need more than 1 at each charge weight. Then, tweak QL until you get the best match to your data samples.

You will find that it is very difficult, if not impossible to get an exact match for some component combinations. I am convinced that there are non-linear effects in the actual powder burn process that QL's linear system models do not encompass. However, if you work at it, you should get the model to match well over the range of velocity that encompasses the OBT you are shooting for. If in doubt, try narrowing the test velocity range around the target OBT node, and try again. Once you get QL calibrated, you can adjust the charge weight in QL to hit an OBT on the nose. That will be your starting load for an OCW type test.

Hope that this helps!

Cheers,

Chris
</div></div>

 

[Clark]

Re: QuickLOAD Max Charge

I use Quickload to find a starting point.
Then I work up to loose primer pockets [or primer pierce in 6mmBR].
Then I back off a safety margin of 2%-4% [Yes,I know Vernon Speer said 6% in 1956].
That is my load.

Then I go back with the knowledge of pressure at the threshold of case head yield and the knowledge of chronograph data, and try to characterize the powder I was using so next time I will be more accurate.

 

[kumaichi]

Re: QuickLOAD Max Charge

I put the pictures up on my website, their over a meg in size. The ones in the back row are the 47.5gr cases. If you guys have any issues viewing the photos, please let me know. They are better viewed if you download them so you can play with the magnification.

Image1
Image2
Image3
Image4
Image5
Image6

Craig

 

[Clark]

Re: QuickLOAD Max Charge

Craig,
I loaded these 308 rounds with one grain more powder with each shot starting from the right and moving to the left.

The last 3 shots [on the left] are short brass life, and too hot.

You can't tell the barely too hot from the barely not too hot from looking at the case heads. You can't tell 7th from the right from 8th from the right by looking at them.

I think you should put new primers into your brass, and if the primers go in too easy, the load was too hot.

If you fire the same load again and again in the same brass, and the primers are too easy to press in before your standards of long brass life were met, then the load is too hot.

To save time, what I do is measure the extractor groove before and after firing. I spin the case around while measuring, and sometimes I have to record a max and a min. If there is ANY growth, the primer pocket may not feel loose on putting the next primer in, but it will within a few shots. So I back off from ANY growth of the extractor groove. Orient the bevel of the caliper jaws with the bevel of the extractor groove.

1) 43 gr. QL= 49 kpsi
2) 44 gr. QL= 52 kpsi
3) 45 gr. QL= 56 kpsi
4) 46 gr. QL= 60 kpsi
5) 47 gr. QL= 64 kpsi
6) 48 gr. QL= 68 kpsi
7) 49 gr. QL= 73 kpsi
8) 50 gr. QL= 78 kpsi extractor groove expands .0020"
9) 51 gr. QL= 84 kpsi extractor groove expands .0020"
10) 52 gr. QL= 90 kpsi extractor groove expands .0110", primer fell out

Looking at these data, I would want more resolution with finer powder increments between 48 to 50 gr. If I found the brass change threshold at say 49.4 gr, and backed off a safety margin of 4% powder charge, that would be 47.5 gr would be my max practical load.

The percentage safety margin required to assure long brass life is dependent on;
a) how accurate and sufficient the data was. If the data is in 1 gr increments, the safety margin must be taken from the point of the highest charge without change. In the top example [with 1 gr increment quantization error], that would be 4% off 49 gr = 47.1 gr max practical load
b) how controlled the reloading process is. If the powder measure is throwing +/- .2 gr, then add another 0.4% to the safety margin.
c) how consistent will the rifle be. If the rifle might be used at high temp or a different rifle is also going to be used, then way more safety margin is needed. If the other rifle has a shorter throat and the bullet will be into the lands on that rifle, then another 4.2% may need to be added to the safety margin.

 

[kumaichi]

Re: QuickLOAD Max Charge

WOW!!! You guys are awesome! I have so much to learn and this certainly puts me on my way. I'll pop the primers out and see if any of them are loose so I can determine if I'm getting close to a max charge.

I weigh each charge (I have the Harrell's powder measure and 1010 RCBS scale). That makes me also wonder why the velocities aren't closer together, if the charge weights are the same, shouldn't the velocities be about the same?

As far as brass goes, will one brand expand more than another? That would mean the max charge could be cartridge specific as well right?

I'm going to head back to the reloading bench and see what I can come up with for this weeks shooting session

.

Thanks again for all of your help, it really is invaluable all of the knowlege you guys have.

I'll post up my results after my range session.

Craig

 

[500grains]

Re: QuickLOAD Max Charge

I don't think I would do that load workup in a Savage 99.