My buddy's grandpa passed and he aquired his firearm collection.  One pistol in particular is very unfamiliar to us.  Any info I could get on this would be greatly appreciated.  

Walther P38

That is a Walther P38.

You have a WWII P-38 pistol.
This on was made by Walther, who used the code "ac" for most of the war.
It was made in 1943 and was gun number 7245 in the "a" production block.

P-38 pistols were made in 10,000 gun production blocks.
The first 10,000 guns made in the year were numbered from serial 0001 to 9999.
Then they started over again at 0001, but added a block letter "a" and went to 9999a.
Then they started over again at 0001b, and so on.
So, you P-38 was made by Walther in 1943 and was probably made sometime in January.

To properly identify a WWII P-38 you need the makers code, the year made, the serial number and the block number.
Since Mauser and Spreewerke were also making P-38 pistols and using the same 0001 to 9999 serial system, it's possible there are dozens of P-38 pistols around all with the same serial number.

That's why you need the makers code and block letter if so stamped to identify it.
It's possible if a P-38 is listed as stolen and all the correct identifying information isn't listed, someone else could be accused of having a stolen gun.

The gun should have the serial number and block letter stamped on the left side of the slide, the left side of the frame, the front of the barrel block, and on the locking block.  All of them should match.

Treat the Bakelite grips gently, they age and can crack or chip.
If you shoot it, shoot ONLY standard load 115 to 125 grain ammo. NO HOT LOADED ammo.
DO NOT install any kind of "extra power" recoil springs,  They can cause the front of the frame to crack through the dismount lever hole.

Thank you very much...

About $1200+ for an AC43 in some circles these days.

Do not use the de cocking lever/safety like you would a Beretta 92/Smith&Wesson/Bersa.
Lower the hammer gently when you use the lever. If you drop the hammer with the lever, you can break the firing pin.

^^ this is good advise.

Also, nice P08 Luger holster. Not uncommon at all. Pistols were lost or exchanged at various times depending on the units role. Holsters would remain and get a new pistol, so in this case.

Screw the gun... I want to hear your Buddies Grandpa's story on how he got it...

As my Uncle Albert said of the German carrying his K98 "He didn't need it any more."

Uh..you didn't think of googling the large text on the slide?

That pistol will/should have nazi eagles w/ swastikas on it probably in a few locations. The P38 (later designated the P1) was used by the german mil into the 90's. It uses a locking cam similar to the M9/beretta 92. Your friend got a nice pistol- tell him DO NOT SELL.

Honestly I thought that was one of the most recognizable pistols ever made. How does anybody not know what a P-38 is?

But, cool gun OP, take care of it.