18 Pr wood box question

[Gspragge]

I don't have a picture of it yet, but some of the markings
are !8Pr HESL , HE makes perfect sense, but SL ?
sounds like separate loading, but that doesn't make sense?

Does any one know?

I will post an image when I get one. Date of box as yet unknown.

 

[hangarman]

SL = StreamLined, so its a more aerodynamic shell with a longer range. I would guess the box is 1930's but they were produced up until 1942.
Cheers
Gary

 

[lulus]

Hi,
Maybe, SL = similar lines (Document attached)

 

[hangarman]

Hi Lulus,
I cant see the reference to SL in your document. SL is for Streamline.

https://www.google.co.uk/url?sa=i&r...ZefZz7pNIZaZTnQrqdxDzSVw&ust=1474814090604188

Cheers Gary