Safety Question

[Amatikulu]

Some further information on your observations and their significance, from my point of view:

1. The "SC" stamp stands for short cone and the "HV" stamp stands for high velocity. They were stamped on the barrel at the time of manufacture to indicate that the chamber of the barrel was made for the Mark VII ammunition which was the standard service round at the time. It has nothing to do with a safety rating beyond the indication that it was suitable for Mark VII ammunition.

2. "DP" is a military designation that a rifle is for Drill Purposes only. The problem with the DP mark is that it doesn't say why it was converted to DP standards as most rifles converted to this had a serious problem, but not all.

3. There is no way that someone sitting on his computer can say if your rifle is safe to shoot. That would be guess work at best, and we wouldn't want anyone to take a risk. The rifle would have to be completley inspected by a very knowledgeable expert gunsmith/armourer. The chances are that for this weapon there are few if any that still exist with the detailled knowledge and tools and even if you found someone, it would most likely be economically senseless. Hence, it is standard practice to not shoot a rifle once its been classified as "DP"

4. "EY" means emergency use only and "GF" means grenade firing. Common markings on rifles that were a little more worn.

5. Now, your BNP mark is a civilian proof mark showing that your receiver underwent proof testing after military use. The mark came into use from 1954. Your barrel should also carry a BNP proof mark...........does it?
If it does, it looks like your rifle was re-proofed once in civilian hands with the aim of shooting it.

Out of curiosity, does any of the wood have the DP mark on it?

These comments are for information purposes and not intended to contradict the good advice you have received so far.
I personaly would not shoot a DP marked rifle as it's an unnecessary risk.