From the J. Rigby & Sons Ledgers

Wednesday March 31 1937

Capt WDM Bell
Brought in .275 H.V. (high velocity) T.D (take–down) rifle with scope in case,
.220 Swift Winchester in card box and .22 Rigby Mauser in cover.
Fit a new barrel to the 275 for H.V cartridge
Fit a gold bead to foresight a shade smaller than the bead on his Winchester
Refit scope Ľ inch forward nearer muzzle
Also if possible fit the scope to the Winchester rifle to interchange with the .275
Regulate scope for the Swift cartridge with 48 grain sp bullet and 150 yards only
Fit a metal collar to forward lenses of scope to prevent rain from getting on lenses
Will call for rifles on Sept 1 or 2
He wants to sell the .22 Mauser. Put on second hand rack
Will accept 10 pounds near.

(Context – WDM Bell was an active deer stalker in Scotland once he returned from Africa and settled down with his wife at Corriemollie in Garve, Rossshire, after he returned from his last African safari trip, in 1924. To the end of his days he was a gun aficionado.
The .275 rifle mentioned is the take down rifle he purchased from Rigby in 1923 for the overland road trip with the Forbes in that year. This rifle was most famously later purchased from his estate by Ruark and gifted to Mark Selby. The rifle was scoped, using a side mount.
The Winchester is the .220 Swift Model 70 that he used on red deer in Scotland. It seems that he had been previously using the rifle with iron sights (peep sight almost certainly, as other of his rifles had been fitted with aperture sights by this period also) Here is having it fitted for the same scope that was on the .275, and has asked for a rain collar or shade to be fitted also. Scotland is very wet.
The .22 Rigby Mauser is a .22 Hipower on a Mauser action (a most beautiful little rifle, I have seen photographs of it) that he purchased from Rigby in 1929, (and was fitted with a cocking piece peep sight.) Again this was a deer stalking rifle. The .22 Hipower he was very fond of even having used on earlier rifle chambered in this cartridge on buffalo in West Africa, but here he is selling the rifle.
My interpretation of this rifle shuffle is that the Winchester .220 Swift is now to be his main deerstalking rifle. )