I believe more knowledgeable collectors will come later and give You more precise info, but meanwhile accept my humble opinions (and please keep in mind I can be wrong) :-)
Your bow looks like Deerslayer with TakeDown option (more details below). Deerslayer was in production until 1950, when it was replaced by Kodiak. Handwritten “BEAR ARCHERY” was used from 1941 to cca 1948 (there was stamp before and then water decals on the latest production of DS (transition models with biglass/woven backing).
Ad Nels Grumley … note, your bow is marked by BEAR ARCHERY only, without Nels signature. As far as I know (and believe) most bows he made have his signature too (see photo below).
Even more, at another thread I found this info :
"… From what I've been told,if Nels didn't make the bow from start to finish,he didn't sign it… ". It could simply mean he just missed to sign this bow for whatever reason, or this bow was made by another person (Nels Grumley was not only bowyer in BA). Or this bow was made after he left company (in 1948) and before biglass backing was used …
Ad TD locking mechanism - this option is advertised in Bear catalog #20 (1947) As I don’t have older catalogs, I can only assume it was available even before.
Now one interesting detail … If You check picture below (comes from cat #20) you can see your bow has slightly different lock mechanism - your has longer “coupling pin”, while catalog version has smaller “crescent”. Not sure why this difference and what it could mean actually (sooner or later production ?)
At last some pictures of TD Deerslayer I have in my collection. It looks quite similar to your one, except locking (crescent). My bow has missing sign/signature at all .. probably removed by later tillering. On the other hand it was signed by Fred in 1983 ...
Hope it helps
TW
---- sorry for my English, I do my best :-)