Here is an estimated chart concerning lot numbers of M42 helmets made. As I believe para helms were made during 3 eras, as stahlhelm 35 was (M35, M40. Helmet Serial Numbers John Burnett Helmet Forum.

Are available right out of the box, no customization required. This chart illustrates hardness and lubricity (Coefficient of Friction) of Ionbond® compared to other. I'd like to compile a list for as many firearm manufacturers as possible.

So if any of the folks here on this forum know of any good sites/links for this, please post them.

Does anyone know of any good websites where one can look up the date of a firearm's manufacture by its serial number? (I did try the search function on here to see if this has been discussed before, but I didn't find it of course, I am old and barely computer literate, so I might have done it wrong!) There used to be a real good site put up by the 'Hoosier Gun Club', with a lot of links to sites where dates could be looked up by serial number, but it is not there anymore.

Para ordnance serial number date