Best friend was cleaning out hes recently deceased FILs house and come across several firearms. One of them is a SVW45 P.38. It is a G seriec gun in the 7000 range.  Finish is probably 90% of the gray phosphate. It has the Metal grips.  It is one of the guns imported by Interarms, so no fancy story like it is a bringback from Vietnam or something. It only had one magazine. No holster or Spare magazine. My friend kept the S&W Chiefs Special NIB from 1980.
He is currently talking to his wife to let me keep the P.38 as I have helped him alot in the past. Honestly, he is the only friend I can trust 100%

I know it will work. All looks strong and firing pin is intact. The magazine was full of Crud and cosmoline, but I cleaned it out. I Field stripped it and cleaned it good.  I have not and will not dry fire it. I would rather fire it with live ammo.  
We just want to fire a few rounds to ensure it functions properly. What would be a good round to fire thru this? I have Winchester white box 115 FMJ, Winchester 9mm Nato, Speer CCI 124 TFMJ Lawman, and Federal Champion 115 grain ammo.  I don't want to run anything high pressure thru it.
Thanks.

These guns were engineered to use standard velocity 124 grain full metal jacket ammo.
They will almost always work fine with 115 grain standard load ammo.

I would say that any of your ammo would work fine.

Congrats.  I dont recommend dry firing them as the WWII firing pin are rectangular under the slide cover though they look round at the back end.  Stress concentrations in the corners can cause these to crack if dry fired.  You might be lucky for a while but the stress will hurt the FP eventually.  The post war FP were redesigned  because of this.  Also make sure the dual recoil springs still feel strong when you pull the slide back.  Wolff Springs sells replacements if they are too weak.  Gray Ghosts are great.  Glad you got a good P.38.  Enjoy it!

Answering your question, *I* would use the Federal ammo. Winchester ammo is known to be less than perfect when compared to other brands of ammo & I wouldn't use them at all. Not saying it would damage the gun, but White Box ammo tends to jam with the least bit of encouragement.

Dry firing can certainly be done with a Snap-cap. A fired casing can be used in a pinch, but obviously safety is paramount when doing that, i.e. not slipping in a live rd when not paying attention.

My .o2

Only use WWB 115 gr,FMJ if you need to take a chance to see if it functions.I don't advise firing it at all because if you break the slide for example-you have totally lost the value of this pistol. It's of course your decision.
Also if you must fire it,never use hot loads-124 gr,+p,hollowpoints,re-loads,and only one round in the magazine(for your safety).
glak

Congrats on the find! Love shooting my old P38 and it loves being shot. :) I've fired many types of standard 115 grain FMJ and all worked 100%. I did try some 115 HP once but they jammed hardcore on the first attempt to release slide into battery. Stick with FMJ and have fun!

You have a French made SVW45 using left over parts that the French found at the Mauser Plant at Oberndorf am Neckar after they captured it earlier in 1945.  You have a true "Grey Ghost" there. a lot of the P.38s went to the French Foreign Legion.