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Brewster11
PostPosted: Sun Jan 09, 2022 11:04 am  Reply with quote



Joined: 08 Feb 2009
Posts: 1301
Location: Western WA

Tony
Benvenuto Cellini devotes several pages in his autobiography detailing his wingshooting exploits nearly 500 years ago. He was especially proud of his little lightweight Italian shotgun which he carried and the skill with which he used it on birds. It’s an interesting side note to his otherwise famous (and not entirely wholesomely innocent) life story.
B.
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MSM2019
PostPosted: Sun Jan 09, 2022 11:48 am  Reply with quote



Joined: 04 Mar 2019
Posts: 1819
Location: Central ND

Tony,

Thank you for explaining things. I probably got about 90% of that.......under the curve is still a bit confusing. What is "under the curve"? What are you looking at? Pressure? Powder gas? Time? Heat?All 4?

Yes I realize that you can change the pressure curve but I don't have older firearms, so I really don't care about the pressures in a barrel past peak chamber pressure.......not absolutely true but.....

When using data or developing my own loads I am always "trying" to get the highest chamber pressure (10,000+ PSI) with the velocity that I am looking for. That mentality puts you in a box, because there are only a few powders that you can use in the 16 gauge to get that done, at each payload level. My reason is that in my travels you have a better chance of achieving consistent velocities and excellent cold weather performance if you start out using the fastest powder you can for a specific application. It also helps patterns (at times) when you don't have a bunch of excess powder gas disrupting things as the wad leaves the barrel. (Kinda why I like ported barrels, it helps with excess muzzle region powder gas when using lots of the slower burn rate powders, but that is another conversation).

Not every load I use or develop follows that criteria perfectly but I do my best. So in my world that pressure curve means nothing. Can't change it, and more importantly I don't need to.

I am a K.I.S.S. kinda guy Laughing Laughing Laughing

Most folks don't realize that you can't look at a pressure curve with data taken from one point on the barrel. I can't remember now where I saw this but a ballistician back before piezo transducers were around had lead crushers setup a regular intervals down the barrel. He was trying to see if he could get SR7625 to have the same burning curve as black powder. Can't remember the details but it sure was interesting and time consuming. I believe that he came close enough with his experiment to use SR7625 in his damascus barreled guns.

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Mark...You are entitled to your own opinion. You aren't entitled to your own facts.
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MaximumSmoke
PostPosted: Sun Jan 09, 2022 4:17 pm  Reply with quote
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Brewster11 -- Thanks, I definitely have to read Benvenuto Cellini's autobiography.

MSM2019 -- KISS is an intelligent idea. Mark (and others), you have the luxury of being able to load right up close to SAAMI sanctioned pressure limits because you shoot guns that were designed for those limits. I, on the other hand, want to shoot some lovely old guns, but cannot trust they are capable of withstanding those pressure limits. It "kills" me not to shoot these guns, and if I'm not careful, it might just kill me to shoot them.

Yes, shooting my damascus barrelled gun, which has not been proofed for smokeless loads at any known level, will ultimately necessitate a proof test of some sort. If the gun passes, I want to be able to verify my loads in the future stay under the pressure level it has survived. Yes, that could mean sending sufficient samples of any load I want to someone like Tom Armbrust. That actually is the KISS thing to do. But, fool that I am, I want more, and I want my independence:

1) I want to compare the complete pressure traces of my smokeless loads to typical black powder loads for which my gun was proofed (purportedly, see the P.S. below).

2) I want to have a standard by which I can check my loads in the future to insure they stay within the limits of my own "proof". I do not want or need to spend the big bucks on a pressure gun just for that, so my relatively cheap-o strain gauged "pressure gun" will be that "standard".

There is no reason for others to do this unless it is somehow important to them. I harbor no illusion that it will be important to many. That this might not be important to anyone else is no reason for me not to do it, however.

Cheers!
Tony

P.S. -- Mark, you mentioned IMR7625. I successfully use IMR7625 and IMR4756 in loads for my W. C. Scott & Sons 10 gauge damascus SxS. The thickness and apparent quality of the barrels of that gun made me feel quite safe to try Sherman Bell's loads, and they are working for me. I still have all my fingers and thumbs. I happened to talk to Morris Baker, the founder of RST Classic Shotshell Co. Inc. and he asked me what loads I was shooting, and confirmed they were the same loads as he was selling, developed from the same source, Sherman Bell's work. Bell's work (in multiple issues of The Double Gun Journal from several years back), indicates it is eminently possible to duplicate black powder interior ballistics for loads of equivalent exterior ballistics in any gauge, by the use of smokeless powders appropriate to the load and the gauge. Just as there is not one smokeless powder that can be used for all loads in all gauges, there is not just one smokeless powder that can be the exact substitute for black in every load for every gauge. Also, not all black powder formulations and granulations act the same, nor do their modern-day substitutes. That is another factor that causes my concern about black powder proofs -- as far as I can see, there is no particular formulation or grind, nor peak pressure level associated with a black powder proof.


Last edited by MaximumSmoke on Sun Jan 09, 2022 5:18 pm; edited 1 time in total
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MaximumSmoke
PostPosted: Sun Jan 09, 2022 5:16 pm  Reply with quote
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Interested in pressure measurement? These guys are way ahead of me! Better to listen to these fellows, rather than me. And no, I cannot afford a traditional laboratory pressure test gun and associated equipment. The RSI stuff seems to do a pretty good job -- according to RSI, of course.

https://www.shootingsoftware.com/pressure.htm

http://www.theballisticassistant.com/ways-to-measure-pressure/
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Brewster11
PostPosted: Tue Jan 11, 2022 1:33 pm  Reply with quote



Joined: 08 Feb 2009
Posts: 1301
Location: Western WA

Quote:
Also, not all black powder formulations and granulations act the same, nor do their modern-day substitutes. That is another factor that causes my concern about black powder proofs -- as far as I can see, there is no particular formulation or grind, nor peak pressure level associated with a black powder proof.


Well noted Tony. The British Ordnance Department has been testing black powder for centuries. They fire a cannonball out of a mortar and measure the distance to determine the quality of a given batch of powder. The same mortar and ball have been used unchanged over the years and the results have been carefully recorded and preserved. Surprisingly, they have found that the black powders from hundreds of years ago performed significantly better than today’s production black powders. The reasons for this are unknown and remain shrouded by the mists of time.

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Dave In AZ
PostPosted: Tue Jan 25, 2022 2:08 pm  Reply with quote



Joined: 13 Oct 2015
Posts: 348

Super interesting, I loved reading this thread. Thx for the great posts! I also would love to have a pressure test system to putz around with. But as I haven't shot skeet for 6 months for various reasons, I'm forced to admit I'm too busy to pursue this interest:( I need to retire!
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MSM2019
PostPosted: Tue Jan 25, 2022 4:45 pm  Reply with quote



Joined: 04 Mar 2019
Posts: 1819
Location: Central ND

Hi Dave In Az,

That's why I am pursing this now because I did retire. Moved to a place where I can use it and not have any neighbor problems.

I have decided to purchase the Pressure Trace System. It just makes the most sense.

So hopefully by April I will have put in my order.

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RGuill96971
PostPosted: Tue Jan 25, 2022 4:55 pm  Reply with quote



Joined: 21 Mar 2019
Posts: 519
Location: Texas

Wonder if we could get them to give us a discount if we ordered several at one time. I would be in on one.
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Old colonel2
PostPosted: Thu Jan 27, 2022 6:44 pm  Reply with quote



Joined: 07 Jun 2020
Posts: 224

I am a little embarrassed to join this thread late. This thread has spurred me to get off my tail and start playing with my Pressure Trace when the season closes.

I do not have as much experience as those who posted on The Pressure Trace set up already.

I am forced to admit I brought the whole set up with extra strain gauges the year I retired along with a single shot model 37 Winchester. All to set up a test gun to develop 16 ga loads for RMC brass hulls. Then my retirement job turned out to be more involved than anticipated and I did not get very far.
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MaximumSmoke
PostPosted: Thu Jan 27, 2022 7:58 pm  Reply with quote
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Hey, Old colonel2, several years ago I bought the earliest version of this book: https://www.amazon.com/Procrastinators-Mind-Why-Procrastinate-Overcome/dp/1647836786 I'll get around to reading it someday.
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Old colonel2
PostPosted: Fri Jan 28, 2022 11:54 am  Reply with quote



Joined: 07 Jun 2020
Posts: 224

MaximumSmoke wrote:
Hey, Old colonel2, several years ago I bought the earliest version of this book: https://www.amazon.com/Procrastinators-Mind-Why-Procrastinate-Overcome/dp/1647836786 I'll get around to reading it someday.


If I had only gotten that book. I need to add to my want list
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putz463
PostPosted: Sat Feb 18, 2023 4:27 pm  Reply with quote
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Location: West MI

Revisiting this interesting info packed thread since I'm strongly considering purchasing a PT system for similar reasons mentioned.

Pulling it forward a year; have any of you folks who mentioned getting one or dusting theirs off and giving it a whirl started using them? Any feedback on performance? Worth the effort or should I just keep sending ammo to PR.

Any info appreciated.

Another consideration on purchasing is the recent changes in the ability to privately ship guns let alone ammo w/o processing through an FFL. Fedex DC refused a box destined for PR a few months ago with some 16 & 10ga test ammo in it. When they saw the little black square they said we no longer accept/ship that kind of package. I dropped it off at a Walgreens and away it went but that avenue probably wont last much longer.

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Sorry, I'm a Duck Hunter so shouldn't be held strictly responsible for my actions between Oct 1st and ice up.
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MSM2019
PostPosted: Sat Feb 18, 2023 5:50 pm  Reply with quote



Joined: 04 Mar 2019
Posts: 1819
Location: Central ND

When I really started looking at why I wanted one, I couldn't justify buying one, and more shotguns, or at least extra barrels, and then having the equipment sit around most of the time.

For the few loads I need tested Tom Armbrust and Precision Reloading are easy to deal with.

For the large percentage of whatever I want to check my chronograph gives me the info I need.

The folks at that FedEx office were either being jerks or they don't know their job. I have always used UPS with no problem, in both CT and ND.

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Mark...You are entitled to your own opinion. You aren't entitled to your own facts.
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MaximumSmoke
PostPosted: Sun Feb 19, 2023 6:36 am  Reply with quote
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Maybe I'll make a little progress this summer when I get back to my shop in Minnesota. I have too damned many projects going -- nut-bolt resto of a J-3 Cub, re-barrelling of a couple of Mausers, motorcycle build, plus there is flying, skeet shooting, golf, tennis and hunting. Damn, I'd probably let all that expand into two hundred years if that time was available, but it's not. I'll just have to do the best I can. I will, of course, apprise this forum of significant progress.

Best Regards,
Tony

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"What we don't need to know for achievement, we need to know for our pleasure. Knowing how things work is the basis for appreciation, and is thus a source of civilized delight." -- William Safire
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putz463
PostPosted: Wed Feb 22, 2023 3:47 am  Reply with quote
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Got it, understand the (busy) life gets in the way of things and also could justify continued use of PR & Mr Armbrust' testing services but I like putzing with things so would get even more satisfaction out of this reloading hobby doing my load development all in house. Heck, all the test/sample loads sent to PR in a search for the (my) optimal 10ga Long Range Goose load in the last few yrs would have justified the purchase on their own right. Still needs some tweaks and now working on the 16ga version. There doesn't seem to be a used market for these so will probably "pull the trigger" on a new unit.

Old colonel2, if you don't think you'll ever get around to working with yours I'd be interested in purchasing the unit from you.

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Sorry, I'm a Duck Hunter so shouldn't be held strictly responsible for my actions between Oct 1st and ice up.
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