Kirby Allen 224 AM progress?

[royinidaho]

[ QUOTE ]

Assuming you measured at about the same point on the barrel I would have expected the temperatures to be closer together. <font color="blue">That's good. I too would have thought they would have been closer together </font>

With a 7mmWby mag I burn almost exactly the same amount of powder as you do. My barrel would be a lot hotter than that . <font color="blue">In the summer my bbl, Rem 700 sporter blue bbl would have been too hot to touch. </font>

There are two questions at hand.

Why did heat production drop so dramatically between shots for 4350? <font color="blue">That's what we'er shootin' for!! Pun </font>

Another couple of shots and there would have been no increase. <font color="blue">I wondered about that when recording it but took extra precautions to ensure that I measured what I measured. Will shoot some more. </font>


[/ QUOTE ]

Thanks for the observations. Helps one to get through his own stinkin' thinkin'. /ubbthreads/images/graemlins/blush.gif /ubbthreads/images/graemlins/blush.gif

Guess I should improve my test setup a bit and do some more shootin' /ubbthreads/images/graemlins/frown.gif /ubbthreads/images/graemlins/grin.gif

The test set up: Cut neck off of 222 Rem. Filled w/J-B Weld Kwik set. Placed this fancy little test device on top of the bbl right at the white spacer behind the fore arm cap.

Just prior to the JB Weld hardening, I pressed wife's pyrex digital thermometer in to make an indent w/the bottom close to the bbl. [Fat chance of finding a thermocouple in southeast Idaho /ubbthreads/images/graemlins/crazy.gif - Could have found one out at the Idaho National Laboratory, but since 9/11 the rules of engagement have changed and my badge ran out Tuesday /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif]

With that gizmo on top of the bbl, it is easy to see that the measured temp is going to be less than the actual bbl temp but the rise should be the same. BBL never got really warm to the touch though. [Think I should build a shooting house then I could control the temperature and remove the effects of the wind. Project for next week /ubbthreads/images/graemlins/crazy.gif]

Here's some more fuel for the fire:
All bullets were Sierra 2600s (250gr spbts)
All primers were Fed-215s
Loaded round weights are:
4350 loads - 586.9/586.3/589.7 grains
RL-22 loads- 563.4/563.1/563.7 grains

Think about that one for awhile. Case capacities for the 4350 loads were much less than for the RL-22 loads./ubbthreads/images/graemlins/shocked.gif

This is why the 338 Win is not a good platform for this swiss navy project except for testing its mechanical aspects.

Test sequence:
Shoot the shot.
Record velocity
Insert thermometer
Watch the temp rise until it steadied out then dropped 0.2 then recorded the highest number.
Then quickly repeat the sequence.

Would have been nice to have a thermocouple epoxied to the bbl, less mass, and a strip chart recorder as I have no idea of what the actual Tstart was for anything other than the first shot. (BTW I don't think even a 12 minute wait gets the bbl back to the original temp.

BTW-a wack w/a plastic mallet removed the test fixture. Then a cloth soaked in Gunk GREEN concentrated biodegradable Concentrated Cleaner plus some digging with the thumb hail removed all eveidence. (Just tho't I'd throw that in, its good stuff)

We'll rerun the speeriment this afternoon. I'm all out of 4350 and can't get enough RL-22 in the modified cases to be reasonable. Think I'll go w/RL-19 or even RL-15???

MOre data added:

 

[Buffalobob]

The graph looks much better. (obviously I am an old school engineer who likes and reads graphs). The lack of any difference between temperatures on the first shot is more apparent.

As you mention the missing piece of data is the pre-shoot temperature. This would give you a better estimate of net increase between shots.

It was my understanding that smaller case capacities would generate higher pressure but the confounding factor of the slightly slower burn rate of RL22 vs 4350 "confounds" the analysis.

I will take a gander around the house for a thermocouple. I can't think of anything that my son has torn apart recently that had one.

 

[Buffalobob]

Well I went and gandered around barefoot out to the garage in the rain. Thanks to all of the global warming, my feet didn't get cold, just a little wet.

I have found what you need but do not have the thermocouple probe.

A.W. Sperry made (in China) a SP-144 volt-ohm mamp tester that could be fitted with an optional thermocouple probe (p-10) and would read out the voltages /temperatures on the dial.

You might go out to your garage and check your volt / ohm meter and see if perhaps it will read too. Other wise check your electonics shop. Oops sorry, I forgot where you live there is only a gas station, post office and country western bar.

 

[royinidaho]

RE: Thermocouple. Have a craftsman DMV #82018 that came w/thermocouple. Who knows where that thing went. Farmers don't have much call for such a thing and that's where I got it.

However the same looking Sears DVM, now Model 82400 is priced at 29 bucks and is packages w/thermocouple. Hmmmmmm, Sears is 30 miles away.........

Am all set up for next test.

Loaded 6 "check" cartridges w/Hornady 225 Interlocks and RL-15 powder. I All 6 cases are w/in a grain of 237.5 grains. Put in 62 grains of RL-15 cause that's what Alliant's book said.

Prep'd 6 "test" caseseach weighing w/in 1 gr of 234.5 gr.

The "test" cases have less volume. I increased the powder charge by 1.3 grains in hopes of attaining the same velocity as the lesser powder charge.

RL-15, volume wise, looks like it will work well. There is maybe 3 grains more volume than I am using. I don't think that case capacity is going to be a problem with this powder.

As my luck would have it, its snowing too hard for testing to be any fun and the chrono goes nuts in the snow.. So I guess I'll have to wait till Monday. /ubbthreads/images/graemlins/frown.gif /ubbthreads/images/graemlins/frown.gif

 

[Northman]

Fiftydriver: have you been able to calculate the BC of the 100 and 107 grain bullets you are using?

 

[Jimm]

What about a handheld laser thermometer . Might be able to borrow one from a mechanic you know .

Sure , swing on by Arkansas on your way to Montana from Idaho, we'll leave the light on /ubbthreads/images/graemlins/grin.gif

Geese all gone north that
ducks never left
Deer season a memory hoarded
like a favorite hat
Spring wont you hurry so
Summer can come
Fall then will follow
The favorite of some
Till then we ponder and wonder anew
Those days of wonder so precious so few

 

[Fiftydriver]

Not yet, need more testing for that.

Kirby Allen(50)

 

[remingtonman_25_06]

I am kinda curious as to what is really being said here. Am I reading it right as, RL powders will burn out barrels more quickly then say IMR powders?? Can someone please explain??

 

[Buffalobob]

Rem
Not much is being said at all. Roy is interested in the 224AM and decided to use the thread to discuss powder temperatures experiments in a 338 Win mag that he is going to have rebarreled. I think he is trying to perfect a method to determine which powder will burn cooler in the 224 AM when he gets one. And he is just using a gun he intends to rebarrel as the test mule for developing his methodology for selecting cool burning powders.

We pretty much had the thread hijacked until somebody un-hijacked it but thanks to Jimm it is un-un-hijacked again. /ubbthreads/images/graemlins/grin.gif

 

[royinidaho]

buffalobob,

You're pretty much correct except for the determination of which powder will burn cooler. What I am attempting to do is to determine if it is possible to get "any" powder to burn cooler. I am making the assumption that a cooler barrel for a given velocity indicates longer barrel live.

What I'm finding out is why laboratories are so expensive. Mother nature doesn't provide a very good one.

Keeping the "environment" constant is difficult if not impossible.

Today was another attempt that had a couple of gotcha's thrown in my Ma Nature and one flub by yours truly.

One thing that is emerging though, is that with a load that has a little less than full of powder behind the bullet, accuracy is definitely improve in the test cartriges.

I alway very much dislike when the researcher, at the end of the report states that "more research is needed." Sounds like the project is being milked. /ubbthreads/images/graemlins/crazy.gif

However in this case, that is the case, just in case your wondering why no definite conclusions are being stated. Which is the case. /ubbthreads/images/graemlins/blush.gif

I have a whole new idea for tomorrow. Instead of shooting a shot then measureing, I'll shot all six shots in very rapid succession then measure the temperature rise.

Noteworty observation is that with the "check" loads, the temperature rises steadily to the maximum. With the "test" loads it increases in stages which indicates, I think, that temperature is flowing.

 

[Buffalobob]

Roy

As you probably know, the "Delta" is what drives the <font color="red"> rate </font> of heat transfer. This is true for the burning powder to the barrel and from the barrel to the air. In order to control delta all through the process, the shots must be equally spaced in time and completed at the same time. Otherwise you could have alot of heat loss during the middle of the sequence and end up with the same heat transfer from the powder but a lower ending barrel temperature.

 

[Jimm]

Thanks , I think /ubbthreads/images/graemlins/crazy.gif

What ? you didn't like my poem of hunters lament ? /ubbthreads/images/graemlins/shocked.gif

I still say the handheld laser thermometer would work , reckon you would need a helper to get the reading as close a s possible to the same point each shot . I know what , I'll bring mine and while I'm at it I'll bring the Oehler along as well /ubbthreads/images/graemlins/wink.gif

Now what did I do with those car keys,

Jim B

 

[royinidaho]

Q=uADeltaT if I remember correctly. Been awhile but.......What messed me up this afternoon was that I had a mechanical problem that took me awhile to fix and the Starting barrel temp. for the last run dropped about 11 degrees below the starting temp for the other two runs. Patience or lack thereof prevented me from warming thing back to the typical starting conditions.

This test is a bit 'basic' to be kind, but am seeing some things. I just don't know what. After today's activities I think that 3 Tcs are needed. Divide the bbl into thirds and center a Tc in each third. All with realtime recording capability.

I don't think its worth all that work though. There are other 'mechanical' problems that need to be conquered first.

I took a drive this morning, and happened to see one yote. He was booking it about 300 yds out and went to about 800 and sat down and watched. Those are the one's I'm after. Two things against me at that time. 1) I had no rifle and 2) I was on the Res. /ubbthreads/images/graemlins/frown.gif /ubbthreads/images/graemlins/crazy.gif

 

[royinidaho]

[ QUOTE ]
I know what , I'll bring mine and while I'm at it I'll bring the Oehler along as well /ubbthreads/images/graemlins/wink.gif

Now what did I do with those car keys,

Jim B

[/ QUOTE ]

I'll keep my good eye out for ya. /ubbthreads/images/graemlins/grin.gif