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Post by Deleted on Dec 20, 2016 19:41:00 GMT -5
When loading low pressure charges that are under 40kpsi with I3031, you will not get a 100% burn even in a 29" bbl. You need pressure to burn the powder faster. It will also be more temp sensitive and have higher es's. IMO, you really need to stay above 40kpsi
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Post by Deleted on Dec 20, 2016 19:48:25 GMT -5
This is more in line of what I might try next.
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Post by Deleted on Dec 20, 2016 20:07:55 GMT -5
One more thing to remember is that chamber pressure with a 209 primer will be approx 3kpsi higher than with an LRMP.
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Post by nyhunter on Dec 24, 2016 6:42:57 GMT -5
Thanks for the report, very interesting.
Look forward to your "cold temp test"
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Post by linebaugh on Dec 24, 2016 10:29:45 GMT -5
When loading low pressure charges that are under 40kpsi with I3031, you will not get a 100% burn even in a 29" bbl. You need pressure to burn the powder faster. It will also be more temp sensitive and have higher es's. IMO, you really need to stay above 40kpsi Where are you deriving this information from? By this train of thought the lowly 45-70 with it's loadings of sub 30k psi with 3031 must really be bloopers.
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Post by linebaugh on Dec 24, 2016 10:45:56 GMT -5
One more thing to remember is that chamber pressure with a 209 primer will be approx 3kpsi higher than with an LRMP. Where is this information coming from? Earnhardt use to speculate about this on Dougs but I never saw any difinitive information relating to it. Does a 209 generate 3,000 PSI? Earnhardt used to speculate that 209s were better ignition and higher velocity also. I'm not convinced either were ever proven since there were never any apples to apples comparisons. If somebody on here wanted to get a pressure trace set up and get a dual ignition gun I would make a donation. I would also build the breech plug for LRP testing or both 209 and lrp. Just having someone pick up where TGinPA (rip) left off would be a wealth of information for the board so if anybody is interested in this please chime in. I will pledge $100 toward the equipment if someone would accept the resposnibility of doing the testing.
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Post by linebaugh on Dec 24, 2016 10:57:17 GMT -5
Pressure trace equipment looks to be $680 or $860 depending on the package. I don't know anything about it and dont want to know as that's simply not my thing but if anybody on here is interested in being the pressure guru please speak up. Also if anybody is interested and willing to donate to the cause lets get a seperate thread going and see where the pledges lead us.
Tim
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Post by jims on Dec 24, 2016 11:20:26 GMT -5
The 45-70 is a bit different as it is a cartridge gun and the bullet upon ignition "slams" into the lands and grooves and might create a different pressure spike. Additionally as I understood an entire pressure strain gauge system ran considerably more than that, I have seen as high as $2500 or so.
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Post by Deleted on Dec 24, 2016 11:23:13 GMT -5
One more thing to remember is that chamber pressure with a 209 primer will be approx 3kpsi higher than with an LRMP. Where is this information coming from? Earnhardt use to speculate about this on Dougs but I never saw any difinitive information relating to it. Does a 209 generate 3,000 PSI? Earnhardt used to speculate that 209s were better ignition and higher velocity also. I'm not convinced either were ever proven since there were never any apples to apples comparisons. If somebody on here wanted to get a pressure trace set up and get a dual ignition gun I would make a donation. I would also build the breech plug for LRP testing or both 209 and lrp. Just having someone pick up where TGinPA (rip) left off would be a wealth of information for the board so if anybody is interested in this please chime in. I will pledge $100 toward the equipment if someone would accept the resposnibility of doing the testing. I don't have time to dig the information up and post it today but I will in the next couple of days. There were pressure traces done that indicated the 209 produced more pressure as seen in the maximum chamber pressure of the trace. I believe that the 209 develops more pressure with less Heat. This has been debated before and can be research on another board. By the way a comparison side-by-side Trace was done with a 2:09 and an lrmp primer and that's where it showed the 209 develops more pressure
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Post by Deleted on Dec 24, 2016 11:26:10 GMT -5
When loading low pressure charges that are under 40kpsi with I3031, you will not get a 100% burn even in a 29" bbl. You need pressure to burn the powder faster. It will also be more temp sensitive and have higher es's. IMO, you really need to stay above 40kpsi Where are you deriving this information from? By this train of thought the lowly 45-70 with it's loadings of sub 30k psi with 3031 must really be bloopers. I got that information from quick load. I will run some traces and post them tomorrow or the next day as I have time
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Post by linebaugh on Dec 24, 2016 11:32:39 GMT -5
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Post by Richard on Dec 24, 2016 11:46:14 GMT -5
Linebaugh..........If you recall, a while back, I was shooting Triplex loads and Edge was not too choked up about it as I had no proof that the loads were safe. Jon, who was always on the forum, contacted me and and said he would purchase the PT system if I would run it? Thinking he was just "talking", I agreed! Well, several weeks later a brand new in the box PT unit arrived at my house. (Jon had my address as I had built him a rifle). Thinking these units were self contained, I got to looking it over and found you needed a Laptop to go along with it? ..........Of which I had none! I called Jon and explained.......to which he said buy one and send him the bill........which I did! Mind you, at this time I had no idea about wireless/bluetooth operation of anything much less a PT unit??? Well, I did a lot of struggling and finally got it going but what a PITA! It was a lot of extra equipment and set up at the range. I like recording each shot and marking my scratch as to each bullet impact along with noting the velocity.......Now I had to deal with PT and logging information and dealing with mis reads due to bumping or banging the rifle when re loading.....figuring out how to eliminate mis traces and on and on and on. I did this for some three months and was posting results on Doug's but getting some discrepancies with TG's readings. In any event, it was more trouble than it was worth! You will have noticed that when TG did traces, that was ALL he did! He never showed groups. I think he had a set up in his garage or on his property where it was convenient to fire a shot and record just the pressure trace and velocity. I don't think he had the distance or was interested in shooting groups. So put it this way, it is a project. You also need a dedicated gun as you have this strain gauge glued to your barrel. But, as you can see from this entire post, the only legitimate pressure reading came from TG and was higher than others posters thought? My advice is this: Do Not take a posters writings that "Its PROBABLY under _____ PSI!" If 90 gr. of 3031 is above 40 PSI with a 300 gr. bullet, than 95 gr. is.........who knows where? We can only say that a given load works and appears safe in the posters rifle. Still, our biggest threat is double loading and doing so in "skinny" barrel! LET THE SHOOTER BE WARE! I am not trying to discourage anyone from getting a PT system, but just illustrating some pitfalls!
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Post by linebaugh on Dec 24, 2016 13:04:28 GMT -5
Richard,
I had no idea how involved it is but I did know I am not a computer or electronics person so someone else would need to champion it. If I would have went through the troubles you describe I would be testing for groups on the actual equipment. Thank goodness for wives and children.
I agree with all you said but my thinking is that the biggest hot button topics on the site are powders and pressures. I still reference TGinPA's traces somewhat frequently and actually had him do a couple traces for me a few years past. Heck his traces are posted here quite frequently. I totally understand TG did not post groups but that does not make his info any less valuable. You (Richard) are the group guy and I think a lot of us appreciate the work you do. I don't have the patience to be as articulate as you are so many thanks for your work.
The bottom line is we really don't know what pressure we are running, how primers are affecting things, how much powder we are burning in X length barrel or any of it. All speculation and opinion and I am as bad (probably worse) than the next guy. In the end unless sombody takes TG's place and gets a grip on pressure tracing we're all doing a lot of speculating.
My offer still stands.
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Post by elkman1310 on Dec 24, 2016 13:11:34 GMT -5
Hi Richard if you recall I talked to you about buying one of this pressure testers because I was concerned about what actual pressures I might be generating. I didn't buy one maybe it wouldn't be a bad investment for a builder to have if you ever got into a legal jam. I don't know for certain how much pressure 96grs of IMR 3031 generates with a 300gr bullet I did have a friend of mine run some quick load data last year and based it off a .458 Lott cartridge. QL can be a little deceiving because we don't use a cartridge case so I does change things a little but IMR 3031 seems to be the only powder that we were able to use to get to the higher velocity of 2900FPS with a 300gr bullet at stay in the low 50K psi range I have to check with Bud again and see if he has the time to play around with QL again.
And yes these heavy charges should never be used in a break action. Or any skinny barrels. If you have a barrel shank that is 1.250 and it is at least straight for 2.00" ahead of the recoil lug and then starts to taper down that should be enough barrel steel to test heavier loads. I said test which means start below 90grs and work up slowly. your barrel maybe strong enough but maybe you breech plug design is not. Safety is the name of the game. Because when it comes right down to it an extra 100 fps only amounts to a few clicks of elevation. Safety and accuracy first.
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Post by Deleted on Dec 24, 2016 14:44:33 GMT -5
Quick Load, as with any computer software, uses pre generated algorithms. In order to even get close to actual trace data in our application, you must first enter pre traced loads into QL to generate data. There are certain things that we have discovered about QL.
Changing case length or COAL is a no no
You must adjust case volume in grains of water parameter to obtain a 105% case fill (compressed load).
Reducing case volume by an extended amount induces erroneous data. So if you need a reduced load go to a 45-70 case or 458WM case rather than a 458 LOTT case like we use for the larger loads.
The reduced friction parameter check box should be checked and set to .40. This is a friction reducing parameter as we are shooting land riders mostly and the lands aren't being cut into.the projectile during firing.
I have ran loads in QL.that come very close to traced loads in both velocity and pressure.
Also, even though a particular load doesn't burn 100% of the powder doesn't mean it didn't go boom or wasn't accurate, etc.
I have contemplated purchasing the software to perform pressure traces. I have several laptops, a degree in electrical engineering, 2 pacnor barrels with HIS AND 209 plugs, and would be willing to go the distance at 50% of the equipment cost. I work evenings and have a range 20 minutes away so I can go most any day.
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Post by Deleted on Dec 24, 2016 15:05:46 GMT -5
Jerry, it would be great if you can do this. A new thread with estimated donations needed would be nice.
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Post by Richard on Dec 24, 2016 20:38:49 GMT -5
Of course the ideal set up would be if someone could shoot right from their barn/garage/house etc. where the equipment could be left set up. Even at 20 minutes away, it means dragging the equipment out if only to do one or two tests. It could actually be a PIA/inconvenience unless you have a more permanent set up. I had also asked TG to do some traces for me (which he did) and I suspect his was a permanent set up. I also believe another reason TG did not show groups is because he only had a very short distance to shoot. Its one thing to do just a trace and another to shoot groups and keep track of shots and locations. If anyone decides to do it, God Bless them! BTW, I sent that unit back to Jon. If anyone would want to contact him they might get it at a good price? I might still have his phone number or address around. He lives in eastern PA just outside of Allentown.
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Post by Deleted on Dec 24, 2016 22:54:17 GMT -5
I just placed an order for a Magnetospeed v3 and plan to contact the maker of the trace equipment early this week. Buying new equipment, I will get a warranty, etc. I will have to build a gun with the pacnor barrel that has the HIS ignition. Having both systems by the same barrel maker, comparison testing will rise to a new level. I will likely do this even on my own if only for my benefit. I will most likely make 1 range trip per week outside ml and rifle season. If I fund the project, I will charge a per trace fee to cover projectiles, powder and equipment. This may be the better option as people wouldn't be donating money to someone they dont know in another state. I have a location closer that I use for jug testing where I won't be interrupted by interested range users.
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Post by hillbill on Dec 25, 2016 12:31:47 GMT -5
Scat Ralf's gun was a unfluted #7 Pacnor with Savage plug, it was several years back when I put it together but that much I remember. I really don't think it would matter who's barrel it is as long as it's the same size shank or close, his was 1.200 for 5" past the lug as I recall. I would bet most makers here in the US use barrel steel from the same manufacturer?
his gun was pretty much dedicated to traces as he kept the pads glued to the barrel as I recall different calibers would also need donor barrels or guns and spare sensors to use, it would not be an inexpensive venture for sure and very time intensive. a switch barrel would be a good platform?
I would be willing to chip in for trace equipment as I'm sure others would as well?
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