Thank you! I was aware when I originally purchased this Tube Gun that it was pretty rare to find an Erb Tube. That was my reason for contacting Charlie Erb in the first place, to find out how many MP38 tubes he manufactured, and that he was able to register prior to the cutoff in 1986. He was unable to provide me with a number, but did tell me they were working around the clock to produce as many receiver tubes as possible prior to the cutoff. Not too sure what his database contains, but I didn't want to press him too much on questions that he didn't have a precise answer for. From my conversation back then with him, I'm pretty certain that they were mostly MP40 and other tubes that he was making at the time. As mentioned on the forum, it's most likely that he only produced a limited # of MP38 Tubes. I'm going to try and contact Charlie again and see if I can get any additional info from him, as well as contacting the ATF, and try to backtrack ownership / registration info up to the point of my purchase. I now realize what Bob was trying to point out to me regarding the font type and numerals on the front of the receiver not being in the Erb style. If a perfectionist type prior owner received the tube when the front of the tube was blank, I guess it could have been possible to find a restoration person, with the correct WaA280 stamps and numeral & alpha stamps, to have the gun serial # & WaA280 stamped into the blank portion of the tube. If this is the case, it was most likely for the purpose of giving the gun a more "authentic look" without realizing the potential problem he would be creating for another owner down the road. I never thought about the front of the receiver when I purchased the gun, all I cared about was verifying that the Erb name and the assigned serial number on the Form 4 was on the underside of the tube. I know with high priced Lugers (Krieghoff & Navy ones), that there are plenty of people out there with the correct stamping devices to turn something into something that it isn't, just to make an extra buck by screwing over an unsuspecting buyer. That issue is a constant topic on Jan's Luger Forum. If a prior owner did that for this MP38, it would not do anything value (being a tube gun) wise, just a cosmetic enhancement for personal gratification I guess. I'll see what I can find out from Charlie, the ATF, and what it looks like under the strap area on the receiver. If I see any signs of this receiver being cut / re-welded, I'll just end up owning a very desirable MP38 parts set. If there are no signs of being cut / welded, I'll see what my research will produce and go from there as far as my options with this gun. Now to try and figure out if I can stop an ongoing GB auction with no reserve and current bids. I'll update this forum with any new information I obtain regarding this receiver. Thanks again to everyone that offered info regarding this gun.