I sure would be curious if any Forum members who own a Model 53 and have a chronograph have tested the PPU ammo vs. some vintage Remington or Peters brand ammo. I bought several boxes of the PPU ammo but have not yet fired any. It does have the correct .222" bullets. The Hornady 40 gr. .222" bullets have been out of production for several years now and I have not been able to find the .223" Sierra 40 gr. bullets for a while either. A gun show seller did have some bulk, new PPU brass and I bought a bag of that as well. The bullets are the problem now.