Lyman 44 cal Mold Numbers

[sw282]

Need some help identifying a couple Lyman 44 boolit molds of mine. ''429215EM''. Also shows the numbers ''867'' and ''07''
My 'Lyman Cast Bullet Handbook' copyright 1973 states 429215 is a 215gr SWC w/gc. Lyman description matches mold.
My question. On 429215EM, what does ''EM'' mean?
Second Lyman mold is ''429244A''. My old Lyman book from 1973 says. Lyman 429244 is a ''250gr SWC w/gas check''.
There is NO gas check groove. The machining is absolutely perfect, showing no signs of additional machining to remove
GC groove. What does the letter ''A'' mean?

thanks.
282

[Maven]

I believe they are the codes for the cherries used to cut the moulds.

[38SuperAuto]

Buckshot posted this awhile back in ForumCasting & ReloadingMolds...Maintenance and DesignFound a webpage with a plethora of old and current Lyman bullet designs

http://ps-2.kev009.com/ohlandl/Cast_Bullet/Ideal-Lyman_Molds/Ideal-Lyman_Mold_Descriptions.html

[MT Gianni]

The 429244 may be a mismarked 429421. Stuff happens.
http://three-peaks.net/Lyman_and_Ideal_Bullet_Molds.pdf
By number both of those molds are a Ray Thompson design and should be accurate if you are willing to buy gas checks.