Space Saver Inflation Bottle Date Coding

[TWS]

Looking for information on the date coding format for space saver inflator bottles.  The Dave Wise book is confusing by saying in one place the dates are in the format of day of year and two digit year (DDDYY) and gives the example of 34070, and on the same page further down saying day-month-year in DDMYY format, and then shows several pics of space saver bottles where the first two digits are impossible days of the month (40, 35, and 41), or the day of year for that matter. I've seen this discussed on other forums with examples only supporting the date format posited by the submitter.  I own a bottle with 49469.  Help?

[headejm]

1970 Challenger RT SE
SPD 508

[TWS]

Not associated with any car (parts purchase).

[TWS]

Being a fairly high pressure bottle, I'm wondering if the first three digits are the lot number, then last two the year. All the bottle dates I've seen so far end in 69 or 70, but the first three digits seem to break every date-coding rule.

[Floyd]

Here's another for the mix.  Bought separately at some point. 

[6bblgt]

it all makes sense    are these all "originals"?

[6bblgt]

   maybe?  maybe not?  maybe someone didn't change the year when '70 & '71 rolled around (maybe they couldn't deal with a first number "0"?)  ..... more examples please

DDDYY
22769 = Friday 8/15/69 * REPRODUCTION
38269 - ? - 365 + 17 = Saturday 1/17/70 * (01770)
38469 - ? - 365 + 19 = Monday 1/19/70 * (01970)
38569 - ? - 365 + 20 = Tuesday 1/20/70 * (02070)
41269 - ? - 365 + 47 = Monday 2/16/70 * (04770)
46369 - ? - 365 + 98 = Wednesday 4/8/70 * (09870)
48369 - ? - 365 + 118 = Tuesday 4/28/70 * (11870)
49469 - ? - 365 + 129 = Saturday 5/9/70 * (12970)
16570 = Sunday 6/14/70
16670 = Monday 6/15/70
17270 = Sunday 6/21/70
17370 = Monday 6/22/70
17470 = Tuesday 6/23/70
22770 = Saturday 8/15/70 * REPRODUCTION
34070 = Sunday 12/6/70
35670 = Tuesday 12/22/70
36470 = Wednesday 12/30/70
40570 - ? - 365 + 40 = Tuesday 2/9/71 (04071)


VS

I'm going to discontinue this format unless it looks like a possible solution

DDMYY
38269 = 2/38/69 - ?
38569 = 5/38/69 - ?
41269 = 2/41/69 - ?
48369 = 3/48/69 - ?
49469 = 4/49/69 - ?
16570 = Saturday 5/16/70
16670 = Sunday 5/17/70
17270 = Tuesday 2/17/70
35670 = 6/35/70 - ?
36470 = 4/36/70 - ?
40570 = 5/40/70 - ?

in this format, what happens to October, November, December (months 10,11 &12)?


VS

WWDYY
22769 = 22nd week 7th day 1969 * REPRODUCTION
38269 = 38th week 2nd day (Monday) 9/15/69
38469 = 38th week 4th day (Wednesday) 9/17/69
38569 = 38th week 5th day (Thursday) 9/18/69
41269 = 41st week 2nd day (Monday) 10/6/69
46369 = 46th week 3rd day (Tuesday) 11/11/69
48369 = 48th week 3rd day (Tuesday) 11/25/69
49469 = 49th week 4th day (Wednesday) 12/3/69
16570 = 16th week 5th day (Thursday) 4/16/70
16670 = 16th week 6th day (Friday) 4/17/70
17270 = 17th week 2nd day (Monday) 4/20/70
17370 = 17th week 3rd day (Tuesday) 4/21/70
17470 = 17th week 4th day (Wednesday) 4/22/70
22770 = 22nd week 7th day 1970 * REPRODUCTION
34070 = 34th week "0" day * BAD example ??
35670 = 35th week 6th day (Friday) 8/28/70
36470 = 36th week 4th day (Wednesday) 9/2/70
40570 = 40th week 5th day (Thursday) 10/1/70

since 34070 may be a fictitious example & the 22769/22770 are known reproductions - I've used 1 = Sunday, 2 = Monday, 3 = Tuesday, etc.

[6bblgt]

..... and on the same page further down saying day-month-year in DDMYY format, and then shows several pics of space saver bottles where the first two digits are impossible days of the month (40, 35, and 41), or the day of year for that matter. ......?

can you post those full "dates"?

[TWS]

The examples I referenced above. 35670, 40570, 41269 

[TWS]

Another bottle I used to own...not associated with a car.

SPDs, if they can be confirmed, would be useful for testing of the proposed decoder (would need a big sample of confirmed SPDs to statistically weed out the delayed or early actual build dates).  One SPD provided in a post near the top.

[anlauto]

All this talk about original bottles....This is one I found in the trunk of a two owner car...a 1971 Challenger....I thought the additional decal was odd....of course I can't confirm somebody didn't add it at some point....but it also seems like a weird thing to "add".

Anybody ever come across another one with the "Danger" sticker ?

[TWS]

Lot number idea not looking promising...where did all the bottles go prior to lot number 382 in 1969?

For the DDDYY, no examples yet for cars built before January 70.

As you mention, what happens with Oct, Nov, and Dec for the DDMYY format?  A, B, C letters we have not seen examples of yet?

Now wondering if it's some kind of shift / day / week / production line combo of some sort for the first 3 digits?

WWDYY?  Week of the year, day of the week, year?  So far that works with the above very small sample.

[headejm]

Currently on EBay. Notice lack of knurling marks on the bottom of the bottle as seen in the other ones above.

[TWS]

Another currently on ebay...a second 16570 for this list.
https://www.ebay.com/itm/195686345244?hash=item2d8fd0aa1c:g:7pIAAOSwzAFkJPYk

[mccannix]

The cannister headjim and 6bblgt's second one pictured are both reproductions from late 80's into early 90's by a well known vendor, about a 5 year span and that was it for them.
He had the seen small lettering incribed on the edge plus put the black silkscreen numbers in place, always either 22770 or 22769.