As far as the reinforcing screw is concerned; it was an official repair or preventative measure originated in British service and even though we don't see it on many British issue weapons, you do see it on Pakistani and Indian Enfields due to the combination of dry and humid climatic conditions. Not all rifles in Indian or Pakistani service had it installed although it is very prevalent in both countries.
Both Pakistan and India have Humid Tropical Jungles to Dry Deserts that can exceed 50 degrees celcius in the shade in the height of the summer. Wood when saturated swells and thus when dried rapidly has a tendancy to crack. Its commonly referred to a 'wood checking' or 'fibre separation'.
One of the reasons why most Pakistani and Indian enfields are dark and dirty is because soldiers would oil their stocks heavily to repel moisture. Motor oil, ATF, BLO, what ever they could get their hands on. Additionally some metal components under the woodline were painted to prevent corrosion. This was common practice.
The kind of environment around Pakistan and India wreaks havock on wood. Thus the reinforcing screw is designed to avoid cracked stocks from CONSISTENT exposure to transitional moist and dry climatic conditions.
This is a bit of a sideline but the wood swelling phenomenon was a major factor in the development of the No4Mk2 (and subsequent Mk1/2 and Mk1/3 FTR). The No4Mk1, No4Mk1* and No5Mk1 have the trigger attached to the trigger guard. The No4Mk2 had the trigger assembly attached to the receiver. This removed pressure variation to the sear and subsequently consistent trigger pull when wood swelling or warpage occurs.
In some circumstances the No4Mk1 would have sear missalignment or pressure to the point where the rifle no longer enjoyed a 2-stage trigger. This can also be observed in No4Mk1 enfields with bedding issues. Knowing this if I had to carry a No4 in the bush for extended periods it WOULD BE the No4Mk2 (or FTR No4Mk1/2 or Mk1/3) not the No4Mk1 or Mk1*.
It usually makes a difference to the price.
I personally do not find this screw to detract from the value of the rifle when you know why they were installed. Regardless
TheTooner seems to be correct. They have always been less expensive to obtain and less collectible (perhaps a good thing for us?). To assume the wood is made of Bananna wood and thus inferior necesitating the reinforcing screw is simply not true. There are some Indian SMLE's with stocks made of Luan Mahogany of which is a very soft species susceptible to dimpling or crushing. Regardless the reinforcing screw was applied to most enfields in Indian service including all manufactures including Canadian, USA, UK, Pakistan and Australian. The Indians did not solely rely on GRI or RFI to fullfill their armamanet requirements.
I have seen lots of people scoff at the prospect of owning an Indian or Pakistani enfield. "Cheap Crap" is the general opinion - idiotic outlook but prevalent. Let them think like that. More enfields for me!
It is a very practical modification considering the region these rifles were intended to serve. I am quite annoyed by individuals that feel the need to patch the reinforcing screw or mask it's prescence in some way. To do so is almost in a similar category to sporterizing - a needless modification that will only devalue your investment (defacing intended purpose and historical correctness).
Well, I figure I have flogged this horse well enough now.
Hope this answers your question.
RIFLECHAIR