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Be careful, myths about pressure signs.

Sticky bolt 264 Win Mag

My grandfather handed me his 264 Win Mag Sako Finnbear which he had for 20 years. Good factory ammo is quite expensive so I decided to start hand loading. I loaded 160 grain sierra tips with 57 gr S385 and 129 grain hornady tips with 62 gr S385. We only get 140 grain ammo in S.A which works well.

I went to shoot in the rifle with the new ammo and found that the 129 grain bullets made my bolt stick that I could only get it open after 5 seconds. The 160 and 140 grain bullets did not give any problems. The primers of all three casings look the same after firing. Can this be a sigh of over loading or too much pressure?

The gunsmith I use said I should seat the tips 1 millimeter deeper, this will bring the pressure down. Is this true or not? The fact that the bolt is sticky, is this harmful to the gun or not?
 
Just how accurate is Quickload? Lately it is being thrown out here as the all knowing infallible answer. Unless manually manipulated, it does all of its calculation with standard factory barrel, factory chamber for which gun and reamer we do not know, assumed H2O capacity etc and "assumed" mag OAL only for seating depth.

changing the seating depth by .100 out on quickload drops 4k pressure for the WSM.

Changing primers based on actual pressure tests can raise or lower pressure over 3k.

so when someone jumps up and says quickload says this or that, just exactly how did they get there. It is only based on the parameters that qucikload used to get their initial data and nothing else. Same as a reloading manual, at least they list exactly what load, primer and oal they used to get their data.

That is exactly why they also caution you anytime you change any one of the above, drop 10% and start over.

BH
 
Actually, Quickload lists 63gr as just over 64k psi for the OAL I'm using. So I am now up at max with no signs, where before I was showing signs below max.

AJ

This is where people get in to trouble with Quickload. The powder charge is irrelevant. It's the velocity you should look at and corrolate with the pressure.

Example: I loaded my Remington M700 24" bbl .280 with 58grs of N160 behind a 140 Ballistic Tip. At the range a 3 shot string gave the following chronograph readings. 3165, 3159, 3162. Very fast...too fast in fact, though it showed no "classic pressure signs". I had a buddy run N160 with 140 BT (with default settings). I seat my bullets out to the lands, so the default seating depth would be less case capacity. Anyway, it puts me in the ball park. It said 58grs should give 57Kpsi, but it also said it would be at 2900fps. Looking down to the velocity I was getting, It said something like 62grs and 74Kpsi. Well, 62 grains would be waaaaaay too much. I read the pressure at the velocity, not the powder charge. Having talked to a couple of gun writers about it, they'll tell you the same thing. Sometimes the powder charges are way off. The velocity, with the given powder, determines your pressure.
 
Bounty Hunter,

I am by no means an expert on QL, heck I cant even figure out half the settings. I can tell you this, it has been very accurate for me thus far. I cannot tell you that such and such load has this pressure, but can show you where QLs predictions were within .5 grain or so of being the predicted velocity in my rifles.

Like any other loading reference you must start lower and use good judgment in devoloping your load. Where I have found QL to be extremely helpful is in its ability to find the right powder. The powder that goes with your bullet and COAL like peas and carrots. As you know some burn rates match certian bullet weights better than others in different length barrels.

I am guessing here because I am in no way a ballistician or expert on internal ballistics, but feel that the limiting factor we all face is the intitial pressure spike. If a powder is the appropriate burn rate it seems that the initial spike will be less and that pressures past this spike will continue to be higher through out the bullets path down the barrel. Based on this IMO there are instances where one powder can give you greater velocities than other powders with less pressure. I keep hearing velocity is pressure from some people and have to agree to some extent, but timing of the pressure curve seems to give a different outcome.

I have only used QL to work out loads for myself in about 15 different custom rifles. In every instance I had my best results with the powder that QL predicted to be the best. In a few instances I learned that a lot of folks pet loads were not even close to being the powder. I may not use the absolute best powder listed by QL because of other factors such as temp sensitivity or availability but always try and use one of the powders that is predicted to be a top performer. It has worked out very well thus far and some of the powder choices are sort of surprising to me. So surprising and seemingly counter intuitive that I have even resorted to using a string to pull the trigger on a 6x284 that I couldnt get to shoot as well as I would have liked. I finally found an acceptable load using QL and the rifle shot pretty well, too bad I had toasted the throat using data from every other source before I bought quickload. Everytime thus far QL has been spot on.

It has also worked very well in working up loads for wildcats. For example my 22-6.5x47 Lapua. When working that load up I used another case with a similar water capacity (I think it was the 220 swift) made adjustments to the case capacity and pressure paramaters and ran the program. I backed off the QL prediction and started working up toward the predicted max. By watching the chronograph and pressure signs (even if it is like reading tea leaves) I worked up to about .5 grains over QLs max. My velocity and presumbably pressure mirrored QLs results.

Until strain gauges become readily available for the handloader I would say a chronograph and quickload results with a bit of good common sense and independant verification where available is about as good as you can get when working up a load.

But then again I do not know that much, but I am learning from all of the posts that more experianced guys here share.
 
There is a way to alter the start pressure if you like to load into the lands that will get QLs predictions to mirror your results and thus make the powder charges closer. I usually run mine with the default start pressure and start lower working my way up to the predicted max velocity. I have never had the predictions off by more than about 2gr.s using this method. Once I adjusted the start pressure, because I was jamming the bullets, it was spot on. As you said velocity is the best indicator.
It is too bad that primers are completely ignored by QL.
 
eddybo,

I'm waiting on a couple of paydays, then QL will be on my own computer. I will learn it inside and out, and may ask you some about it more then. I know it does a lot of things. You can also customize it to your brass capacity too which can greatly affect pressure.

From your above post, you seem to have a handle on velocity vs. pressure, and even better (something some handloaders never grasp) is the effect of burn rate on pressure.

I write on online BB's a lot about the .280Rem and the loading I do. Most often I'm told I'm loading way too hot. I tell them I've loaded that way for years with no probs...they say my time is coming one day. Now with QL I have something to back up what I say is safe, and out come the computer software poo-poo'ers. Well, let me tell ya. NASA doesn't shoot rocket after rocket to get the actual data for a real launch, they use prediction software like QL. It's good, tested, solid technology. It works.

I love reading people say "I'm at book max, and it's 200 fps slower...this data is way too optimistic." No, you just don't understand how to read it. They all know that lots of powder can vary, sometimes greatly, yet they think they're supposed to get the same velocity with the exact same powder charge and bullet. Why?

I load this way. I'll use my .280 as an example. Nosler data says I can get 3150 with 57grs of R-19 in a 26" bbl. Hornady says with their 139 and 57.4grs of R-19 I can get over 3000fps in a 24" bbl (Hornady doesn't give exact velocity, they step theirs ever 100fps). Now I got two sources telling me that 139/140 class bullets and R-19 can get between 3000-3100fps in a 24" bbl. (I figure the loss of @ 50-75fps from Nosler's 26" to my 24" bbl and QL bears that out along with other data I see online.) Now, I start my loading by working up from abut 55 grs of R-19. I know that all .280 data is produced at 60K psi. I know the SAAMI for the .270Win is 65K psi, so it's safe to load it up to .270 pressures if I want, or keep it down to 60K and have that extra cushion. I load up to .270 pressures. So basically, I get back the 50-75fps I lost with Nosler's 26" bbl. Now, I simply work up to my target velocity, and the number of grains of powder are only used to get me a reference for a starting point, and if I am at 3100-3150 when I hit 57 grains, then I'm at max. If I hit 3100-3150 at 56 grains I'm at max. If it take me 59 grains (which it does in my gun) then that is max regardless of the listed max powder charge in the book. The "real listed max" is the max velocity. And now, as a final check I consult QL. It tells me my velocity with the 140 BT is around 62K psi but takes over 60grs of R-19 to get it. (why the powder charge is not the way to look at QL) The pressure is even lower with the 139 Hornady due to shorter bearing surface. So, all the data I have indicates that I'm safely in the good on pressure at velocities many say you can't achieve. When you run the numbers using the faster burning powders many of these folks use, then you see why. Even stepping up in burn rate just a tad to H4350, the same velocity gives as much as 2K psi more pressure. And to the other end, R-22 will give about 2K psi less pressure at the same velocity as R-19. In fact some data I have here on my work computer that someone sent me suggest that you can run the 139 Hornady over 3100fps in a 22" bbl and still be under 65K psi. Many loaders that simply look at book data will tell you that's impossible and asking for a nuclear holocaust! You suggested, and I concur, you must match the powder to the bullet wt and case capacity, and if you do, you can get great results.

I also concur with the original poster in that many times people think they see pressure signs, when in fact they're misleading. The oversized firing pin hole making cratered primers is a classic example. A rough edge on the bolt face creating "shiny spots" is another. Even flattened primers can lie, as the different manufacturers have greatly differing hardness, and many factory offerings flatten primers.
 
Eddybo

Guess what I am saying is too many times we see QL used in another way, that will build a false sense of safe load or max pressures when reality might be just the opposite.

"Someone run QL for me and see what my pressure will be this weight powder"

QL says that this is the pressure this load must generate!"

No, QL does not compensate automatically for different seating depths, (want to have fun run QL on our famous 75 gr V550 and 300 WSM with 125 BTIP and change the seating depth .100 and see how much pressure drops). That is highly probable also in single shot version. it does not know which primer you are using which can change pressure 2-3k alone. Plus it has a default H2O capacity that might be right on or might be way off one way or the other.

QL allows you to change the bullet friction coefficiant function and alter the pressure and velocity also.

If you use QL smartly to try and figure which powders and likely loads and then work up like you said that is a great use. However, we are seeing more and more people asking and trying to say this is the "definitive exact load" and start there or this is "the Pressure of a given load", when in fact reality is that is just a WAG based on the default settings of QL, with no seating depth variance, no primer info, no H20 capacity info etc.

That is dangerous in creating a false sense of confidence or a false sense of that is unsafe.

Any way that is my take.

Used smartly it is great, used dumbly well that is another story.

BH
 
I went to shoot in the rifle with the new ammo and found that the 129 grain bullets made my bolt stick that I could only get it open after 5 seconds.

Was it only the first two rounds or did all of them stick? The reason I ask is that most of us old timers were taught by our Dads to put a lot of oil in and on our rifles. Perhaps your Granddad oiled it up real good for you so you wouldn't have a rusty gun. Oil in the chamber can cause the case to slide back instead of gripping the sidewalls. (So can water if you decide to hunt in the rain.) This causes extreme rear bolt thrust.
 
Man you better watch it the pressure police will get ya:)
There are people out there shooting loads that are dangerously hot that could be getting better velocity using safer loads. Matching the componants together seems to be the key. QL allows you to envision the results. I dont even post the velocities I get with my 30/06AI and 208 A-Maxs lest the pressure police come knocking, even though I am pretty sure the load is within saami spec. If someone tried to get the velocities that I have obtained with different componants things could get dangerous pretty fast. There is a post near the top today regarding .308s at seemingly impossible speeds with heavy bullets. I think that performance near that listed is posssible safely with normal pressures, even though at first glance I thought it was a dangerous situation. Some small changes in componants and 2800fps in a .308 with 190gr bullets becomes a bomb.
 
Bountyhunter, you posted while I was already responding to .280rem. I am pretty sure I ran QL on that exact load as you defined with a longer seating depth, I maybe even ran it using moly back when it was a hot topic. I do not think I ever was ever able to get that load to pressures that I felt were safe or even close to safe in a factory rifle. I do not think the issue was whether it could be safe in a rifle in a special cut chamber, which maybe could be done using high but probably safe pressures...ie a couple of reloadings. To me the issue has always been what can happen when someone uses this load in a factory rifle.
I am not going to rehash that here. Maybe we outta just let dead dogs lay.
I do see how QL could be used as you say, but I do not think that it was used as you think. In fact I think that it was purposefully used as intended, to allow people to see what would happen with a specific load under a given set of paramaters. I do not remember who posted the results in that thread but I am almost positive they were correct.
 
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