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Post by Richard on Dec 15, 2010 21:36:55 GMT -5
OK, Edge has brought some points that I have to look into. Right now, I have the trigger sensitivity set at "5" which is sort of where the company recommends.......actually between 5 - 10. I plan on talking with the people at the Trace company (RSI) and maybe send them the traces along with my load information. I just went into my "barrel configuration" in the program because there was a number I had left out............  Thinking that this might have influenced the readings...........................NOT? That figure was the bullet diameter. However, when I looked in the program, I found that bullet diameter was not one of the required fields that need to be filled in to get pressure traces. I did, however, add it  Edge........if it means anything, those misc. traces along the bottom of the graph seem to occur from the handling of the rifle. I tried to be very careful and it did help some. So, I don't think they are coming from pulling the trigger? If you note, I do have several traces in succession with no in between lines at the bottom. I tried disconnecting the wire at the instrument but then got jammed up when I apparantly lost connection with the computer. Also, I questioned why the psi readings on the "saved" file differed from what I had physically recorded on my work sheet? Richard |
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Post by pposey on Dec 15, 2010 21:44:24 GMT -5
aint technology great,,hehehe,,, I'm thinking you will uncover some great data once you get the bugs out
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Post by edge on Dec 16, 2010 3:30:07 GMT -5
I did not mean the low lines as regard to the trigger, I meant what seemed like a delay in the trace itself.
If you look at the first trace with 62 gr. of H4198 the trace is zero for almost 0.6 ms...I have to believe that something triggered the unit Other than the primer going off! The same for one trace in your 3069 fps load and one in your triplex load!
edge.
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sr71
Spike
Posts: 38
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Post by sr71 on Dec 16, 2010 12:06:51 GMT -5
Richard.. Big thumbs up for having the gumption to try something even if you think you are technically handicapped! I personally look forward in watching your progression with your new "toy" Stay safe!!
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Post by spaniel on Dec 16, 2010 12:24:37 GMT -5
For being "technically challenged" you are doing quite well out of the gate!
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Post by Richard on Dec 16, 2010 14:39:50 GMT -5
Edge..........Ok, gotcha. Look, I am going to construct an e-mail and get it off to RSI along with the traces and see what they have to say. Then maybe a phone call after that.
Richard
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Post by edge on Dec 16, 2010 15:04:58 GMT -5
I just figured out that this was a test and we failed ;D
I could not figure out what you were talking about with the different pressures.....that was why I did not address that before.
The log sheet you posted with the traces was from last week!
edge.
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Post by chuck41 on Dec 17, 2010 0:54:09 GMT -5
Just curious. Isn't there a way to clear the screen after you have loaded your gun and placed it in the sled before you actually shoot?
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Post by edge on Dec 17, 2010 6:34:35 GMT -5
I don't think so chuck, you can delete the last shot though. For someone new there is a lot to think about the shot you are about to make, loading, checking the chrono, checking the trace unit, etc. A two man team would make life much easier  edge. |
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Post by tar12 on Dec 17, 2010 7:13:37 GMT -5
Edge,
I wanted to follow up on this as it is incedibly important to keep this valuable info as clean and as straightforward as possible.
"I think that we should have a thread for Richard to post traces without replies and a second thread for replies.
This is important data and I really would prefer that the data be archived as is."
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Post by edge on Dec 17, 2010 8:20:32 GMT -5
The original thread is locked...a little too late  There is a thread just for Richards links in the Load Forum RICHARDS PRESSURE TRACESAny mod that sees Richards trace data should lock it immediately. edge. |
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Post by ET on Dec 17, 2010 10:08:34 GMT -5
Richard
First off I want to commend you for taking on such a task with the Pressure Trace Unit. At first glance it appears the unit is somewhat complicated with all the factors as well as the instruction manual. To some this may appear intimidating.
It will take a little time to gain a good familiarity with it and with your initial results you are well on your way.
After reading through the manual a few times for trying to get a better understanding of the principle for the units operation for a better picture of what transpires I am intrigued with my findings.
The basic here is the recording of change in micro-amps derived form strain gauge when a change in micro-ohms occur from the resulting pressure applied to the barrel steel causing it to micro-stretch.
The change in micro-amps causes a monitor gate (electronic trigger) to begin the recording process. So when the sensitivity level for the start of the recording process is changed (increased) unwanted lines near the bottom are not recorded and your graph is also moved to the left because your starting point for recording has changed. This in no way should alter the peak recording.
Isn’t electronic gadgets fun to play with? ;D
Ed
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Post by Richard on Dec 17, 2010 16:56:52 GMT -5
ET..........all I have to say is...........  ! The letter went off to Jim Ristow at RSI and a response received. I shared this with you land Edge.(since you have a unit). I don't think Jim's replies are of any value to the forum itself. I Edge thinks it should be shared, he is welcome to do so! This is a learning process for me so be patient ;D I will say this, Jim did think the parameters I used were good and the traces looked good. However, without any other traces from other ML's he could not make any comparison's. Richard |
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Post by boarhog on Dec 17, 2010 17:24:59 GMT -5
Would the traces from RB's www apply, or be helpful?
BH
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Post by chuck41 on Dec 17, 2010 18:44:57 GMT -5
Would the traces from RB's www apply, or be helpful? BH Probably not. They are all on 50 cal guns and there is a very large difference between ignition of 50 and 45 caliber guns like Richard is using. |
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Post by spaniel on Dec 17, 2010 19:09:21 GMT -5
As I look back through RB's 50cal traces, I did notice that at one point he mentioned that a group of them read substantially higher than previous runs and attributed it to using a different gun and setup.
Do we have any load in a 45cal where the pressure is known, or estimated with good certainty, or is known to be considered a "max load"? This would be a good standard to run. Richard, given the issues you have had with gas getting around your firing pin etc, and the fact that RB did not report this while apparently shooting loads and running traces at what are supposedly similar pressures, I am still worried that the setup is accurately calibrated and not reading low.
Again, thanks for all the work you are putting into this. As you get more loads the cross-comparison will be very informative, even if a good usable standard is hard to find.
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Post by ET on Dec 17, 2010 20:02:11 GMT -5
Richard
Using the PT unit for muzzle loading is kind of sailing into uncharted waters with new parameters to explore. Just think you are a pioneer with generating pressure traces with the smokeless muzzle loading 45. Where few men have gone before.
Here a co-operative approach might produce a more accurate or reliable reading. But this has to start with a single powder load. Starting with a specific single powder load and if Edge doesn’t mind checking what QL says for expected pressure, then compare what the pressure trace shows with the calculated pressure. Once we know the difference between the two a plan forward could be developed to proceed in a specific direction to try and obtain the best traces possible. Basically take it one step at a time.
Just out of curiosity, how many strain gauges do you have available?
Ed
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Post by redspinner3 on Dec 17, 2010 22:44:50 GMT -5
Richard mind me, as I'm no expert, but if you take a known rifle and cartridge like 45-70 with known pressure trace and hook your pressure trace instrument to it and duplicate the trace. then your insurgent is calibrated. then connect it to your rifle,you should be in the right ball park to start tracing. know you start with a known value seems to me.
George
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Post by spaniel on Dec 18, 2010 7:16:35 GMT -5
Richard mind me, as I'm no expert, but if you take a known rifle and cartridge like 45-70 with known pressure trace and hook your pressure trace instrument to it and duplicate the trace. then your insurgent is calibrated. then connect it to your rifle,you should be in the right ball park to start tracing. know you start with a known value seems to me. George The problem is that moving it to a different rifle would not calibrate it. It is specific to the current setup. Shooting a load made for a .45 straightwalled cartridge, using the same bullet, MAY get you close although things like sabots can even change that. Relative calibrate may work satisfactorily. By this I mean comparing back to a load where the pressure may not be absolutely known, but it is widely accepted as say a near-max load. Then if you are testing other things and getting much higher numbers, you'd know to be concerned. |
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Post by ET on Dec 18, 2010 13:10:38 GMT -5
ET..........all I have to say is........... ! Richard Richard Okay I can see why you’re reaction was as such. ;D Got my feet wet today and started setting up own unit with an older lab top I have. Now this was fun with some obstacles to over come. First off my lab top didn’t recognize the CD nor would it run on the disc drive. Okay went to my desk top and same response. Next step I went to my desk top that had the newer version downloaded from RSI and transferred this to my lab top with a memory stick. That worked out okay until I went to download the 2-USB programs necessary for operation. For some reason the 2nd USB didn’t load properly and had to remove the first download attempt and try the double download again. After an hour of fiddling around my lab top is now communicating with the pressure trace module. Yippee. My unit doesn’t have blue tooth capabilities so USB connection is required. Okay phase one complete and will take a break here. Next it will be taking careful measurements for the variables and installing strain gauges. Having quick detach scope mounts should help simplify the next step with access to the barrel for installing gauges. Okay it’s not the most user friendly to start with but I’m having fun getting started. ;D ;D Just have to be patient as one progresses.  Ed |
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Post by TGinPA on Dec 18, 2010 15:54:50 GMT -5
Years ago, I acquired one of the earlier Pressure Trace setups (firmware 3.90) but never used it because it was overwhelming and RB covered any question I wanted to solve before I could get it up and running. Now that Richard is addressing its use to PacNor 45 cal barrels and there is so little out there for comparison maybe I can help as a different but limited source of data. FWIW: Here are two traces shot using the load and bullet he posted. I think these are in fairly close agreement with his findings. Agree with spaniel: For purposes of comparison, the more we standardize our setups, the better. For instance, my limited experience with effect of barrel temperature on pressure recordings suggest that this might be an important factor to standardize, particularly with slower powders. If we get a bunch of us contributing, it will be a tribute to RB and the pioneering work he did. Computer: Dell Inspiron Mini Notebook Gage and Module Manufacturer = RSI USB model Trigger Sensitivity = 5 Strain Gage Voltage = 4.9 Gage Factor =2.1 PSI Correction Factor: None Barrel Temp = Not measured (est. 60 F) Rifle Stand: Caldwell Lead Sled Chronograph Chrony Alpha Model Barrel Type: PacNor .45 Cal Stainless Muzzleloader Breech Plug: Pa Machine Recessed (screw-in ventliner) Barrel OD = 1.052 in Barrel ID = .454 Bullet Diam.= .450 Bullet Type = Barnes Bx unknurled Bullet weight = 195gr Sabot: Harvester Light Blue Crushed rib. Powder: H4198 62gr Primer: Fed 209A Shot fm clean barrel, 1 patch Bore Shine, 1 dry patch   |
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Post by Richard on Dec 18, 2010 16:22:17 GMT -5
TGinPA..........Thanks for putting up those traces. Temperature wise we are about the same asour shootng room is heated to the mid sixties. Looks like we are at least in the same ballpark or thereabouts! The thought of running traces on a 45/70 sound ( ) and then where do I get a slave gun to glue a $30 strain gage to? Look, this is not like...............well just move the gage to another rifle The gages are expensive and are not readily reusable! At least I have not tried to successfully remove one without FUBAR ! If you get my point. Then again the thought of pressures in a cartridge rifle with throat that has to squeeze down that bullet (while building pressure) (as opposed to a bullet or saboted bullet going down from the front without this throat to constrict it? This, is not comparing apples to apples! I have asked Edge to designate a load for me to shoot on Tuesday. Maybe TGinPA could shoot the same load? Maybe Edge could run up to the "Tunnel" and shoot it on his instrument then we could compare? I don't know exactly how we can work this? I kind of got volunteered by Jon and I'm trying to do my best. The head honcho at RSI says: And this is a quote from his response to my e-mail: "I can only comment that the traces are nice and smooth with the correct shape. No indication of disconnections, etc. Some seem to have a bit of a secondary event but that may be after bullet exit. If your barrel dimensions are correct and the barrel is Chrome Moly, the pressures should be accurate but it is always best to try to correlate it with another reference. I would enter the velocity to see where the bullet exit is re the secondary bumps. It could be deflagration at the muzzle." Richard |
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Post by redpep on Dec 18, 2010 18:20:23 GMT -5
From my earlier reading the strain gages are not reuseable. I believe that they are glued on to the test gun after some very extensive cleaning at the attachment site. so if some body wants to cough up a couple more gages than the critical point would just be switching the leads
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Post by ET on Dec 18, 2010 18:24:06 GMT -5
TGinPA Neat, 2011 could be a jamboree for Pressure Traces. I also like your thought about dedicating future work to RB for his pioneering in this area. While reading deeper into the PT manual for Version 4.5.0 info I came across 2-interesting features I was not previous aware of. 1) This unit appears to be able to calculate muzzle velocity. 2) Also has a feature called optimum barrel time OBT. On the bottom of the graph are indicators that show best time points for the bullet to exit the bore and on the graph line when the bullet actually exists the bore. Mind you a little hanky panky substitution on the barrel setup sheet is needed because this was more meant for cartridge rifles. This is one case where a little white lie told to a calculating machine isn’t going to bother my conscience. Richard will probably beat me to these additional features as I have to wait till Spring to get my end of the ball rolling. By then the learning part of my tinker blood should be hot to trot. ;D Ed |
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Post by spaniel on Dec 18, 2010 18:30:43 GMT -5
This is great to have traces of the same load from another source. The difference is not huge, but 5-7K psi higher on Richard's? With no knowledge of which is more accurate, I would say that if 40K is agreed to be the upper limit that the safe thing to do would be consider 35K on Richard's setup as the max. TG's MAY be low, but Richard's MAY be high...great great info!
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Post by chuck41 on Dec 18, 2010 23:55:00 GMT -5
TGinPA Neat, 2011 could be a jamboree for Pressure Traces. I also like your thought about dedicating future work to RB for his pioneering in this area. While reading deeper into the PT manual for Version 4.5.0 info I came across 2-interesting features I was not previous aware of. 1) This unit appears to be able to calculate muzzle velocity. 2) Also has a feature called optimum barrel time OBT. On the bottom of the graph are indicators that show best time points for the bullet to exit the bore and on the graph line when the bullet actually exists the bore. Mind you a little hanky panky substitution on the barrel setup sheet is needed because this was more meant for cartridge rifles. This is one case where a little white lie told to a calculating machine isn’t going to bother my conscience. Richard will probably beat me to these additional features as I have to wait till Spring to get my end of the ball rolling. By then the learning part of my tinker blood should be hot to trot. ;D Ed Now if these things calculate muzzle velocity, that would offer you a secondary way of getting an accurate calibration. That means the system is taking the pressure trace it measures and calculating the acceleration of the bullet based on that pressure from initial resting point until the point at which the bullet actually exits the barrel. If you measure the velocity on a good chrony and translate that from the 20' or so out, back to find actual muzzle velocity it should match very closely the velocity calculated by your pressure trace device. Then all you have to do is make sure the barrel setup that TG referred to gives it a good indication of the initial bullet position like as if it were a 45-70 or something and the actual distance from that point to the muzzle. If actual measured muzzle velocity is higher than what is calculated by the pressure measuring device it means that the pressure readings are too low. If it is slower, that indicates the pressure readings are too high. A few tries and you should be able to get a pretty darned good calibration that you can depend on. (Unless of course the readings are highly inconsistent in which case you know you have wasted another perfectly good day. ) Gee what fun!  Should keep you off the streets and out of the bars for quite a while! ;D |
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Post by jims on Dec 19, 2010 3:20:18 GMT -5
chuck41: It could drive one to drink. This should prove interesting.
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Post by edge on Dec 19, 2010 8:09:02 GMT -5
If the new units calculate velocity that would be great, but the old units do not as far as I know.
What I have done in the past is to shoot over a chrony and manually add the velocity data to the computer. Then the computer adds the OBT data to the trace.
edge.
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Post by ET on Dec 19, 2010 8:56:10 GMT -5
Chuck41 Here is what the Pressure Trace Unit can provide for muzzle velocity.  Here is what the Pressure Trace Unit can provide for barrel time.  If I read your post right you are implying by using velocity comparison between the pressure trace unit and a chronograph to calibrate or verify a pressure reading. In other words a specific pressure should generate a specific velocity. To be honest Chuck that after trying to intertwine all the different variables together I can’t picture this as being a reliable method. The pressure trace unit is based on the barrel material stretch for a given thickness causing the gauge to stretch changing it’s resistance that in-turn changes the amount of numerous amperage readings recorded in a specific time frame. Now this is also dependant on supplying the unit with accurate specific material dimensions. Velocity is another function that is dependant on barrel time. By rights I could alter the pressure reading by what I input and still get the same barrel time. The two key elements that I see at the moment is the strain gauge being located at the point where peak pressure is obtained and correct specific barrel dimensions at the gauge location. Being that a muzzle loader doesn’t have a chamber with any kind of a shoulder then it’s possible that the peak pressure may possibly not be were it’s suggested. It may even be spread out over a wider area because of lack of confinement that a chamber may produce. Originally when I bought my unit I purchased additional gauges, 4 in total. One gauge was designated for my 300WSM load development. Because there is no specific precedence or established known with pressure testing a muzzle loader IMO some additional research is needed to verify parameters to work with. Jon you had to get the ball rolling with pressure testing. Here I will say thanks for getting my butt out of its inertia state of rest in this area. ;D ;D Ed |
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Post by TGinPA on Dec 19, 2010 9:37:29 GMT -5
Richard: As time permits, I will try to make traces for comparisons with any loads you test.
Pressure stretches the barrel and we attempt to measure the stretch which is affected by pressure and barrel elasticity. As I begin to think about comparisons between different barrels, I worry a lot about effects variables which I can’t control or fit to some standard. For instance, how does barrel composition (chrome-moly vs stainless), barrel manufacture (heat treating, hammer forging vs cut rifling, etc) affect molecular structure and elasticity of the barrel? If so, how does this affect our reading and can a reliable correction be applied?
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Thinking that this might have influenced the readings...........................NOT? That figure was the bullet diameter. However, when I looked in the program, I found that bullet diameter was not one of the required fields that need to be filled in to get pressure traces. I did, however, add it 
!
Should keep you off the streets and out of the bars for quite a while! ;D