If you could get a picture of the barrel lug and cams that would help date the gun as pre-1950s or post 1950. There were a few improvements made to the BHP in 1950. One of which is the dimensions of the barrel lug and cams. There are other ways to tell as well but require more breaking down of the pistol to inspect the mag safety design.
As to value it is much closer to $1000 than $500.
When you are looking at guns of this age it is all about condition and originality of the configuration. You need to make sure the grips are period correct, that no parts have been replaced, that the gun has not been reblued in anyway, on this particular gun I would hope the magazine disconnect is still intact or at least the parts are coming with the pistol.
One thing to consider is that the internal exactor is a know failure point. If shot enough they will break. It is not a matter of if IMHO it is a matter of when. So if you are buying this gun as a shooter that is a serious consideration because when it breaks it will cost about $75+ to replace extractor with a surplus piece if you can find one and the value of the pistol will be hurt by the replacement part.
If you want to talk more via PM I can give you some more detailed thoughts.
I'm trying to determine date of manufacture for my FN P35. I've been to the more obvious sites like 'fnhipower.com' and some others and they all seem to have the same serial number list, which I suspect may be for 'Browning' marked guns. Using the list they show would indicate my gun was made pre-1957. I'm going to list what information I have and maybe someone can point me in the right direction.
1, It's a standard blued HP that came with fixed sights and has the usual Belgian proof marks.
2, It has a 5 digit serial#, 45XXX, stamped on slide, frame and barrel. There are no letters or other symbols in the number. The 'fnhipower.com' list starts at 1957 with ser.# 70000
3, I bought it, in Germany, in 1972,'unfired, second hand' from the original owner, who stated that he had bought it new at the base US Army Rod and Gun Club in Germany approx 2 years before. This leads me to suspect that there 'may' have been different serial# blocks for european market HPs
4, The slide is marked with the standard European 'Fabrique Nationale d'Arms De Guerre - Herstal Belgique - Browning's patent depose' and has the disassembly notch on the right side.
5, The extractor is the old style(like a 1911 colt), the only mention I've found of date of implmentation of the newer, pivoting style extractor is 'sometime post war', I suspect somewhere in the 1960s. I seem to remember reading about the changeover sometime in the distant past, but that was too long ago to be certain.
So, does anyone have any ideas here? Was this HP made pre-1957 and unsold until 1970 or is there another explanation? Any help would be appreciated.
Don in Ohio
Browning Gun Values By Serial Number
Dec 23, 2009 - Browning High Power Serial Number Date Codes. Location: Florida. Weird, my Hi Power serial isn't on the list on Browning's website. Pick a model from the left hand menu.
Belgium Browning Hi Power Serial Number Location
The 9mm Hi Power pistol was introduced to the U.S. Serial numbers from 1954 through 1957 are estimates only. From 1958 on, better records were kept. Dating Browning Firearms Post 1958 Manufacture. This dating system is for Browning firearms manufactured after 1958. Cornell Publications has a link to the Blue Book serial number listing, this listing can be saved. Under the Browning listing 16 gauge the note is: '1957-58 Prefix 'T' for Standardweight and Prefix 'A' for Sweet 16 numbers mixed, but range from 1-10900. Pick a model from the left hand menu. In 1975 Browning standardized its serial number identification which it followed until 1998. Serial Number beginning with 01001 at the start of each year. It's a Mark 3 with a cast frame. You should see grooves in the frame on the bottom of the magazine well.