New Member - 4MM M20 Question

Hi, I’m new to the board. I’m mostly a C&R semi-auto collector, and a recent purchase brings me here. I picked up a 4MM barrel for an Astra 300 that looks to take 4MM M20 cartridges with an adapter of some sort. I found a thread on this site that seems to picture what I have: viewtopic.php?f=8&t=6647&start=45

Here are photos, including on showing what I believe it the adapter cartridge (from this site).

Am I correct, and does anyone know where I could purchase a few of the adapter cartridges?

Thank you, … l.jpg.html … u.jpg.html … a.jpg.html


Welcome to the forum.

Adaptor cartridges are not my area of collecting but as far as finding some of the 4mm rounds you are after, below is a link to a listing of places to purchase collectable cartridges:


The 4mm Ubungsmuition M.20 is briefly discussed on the forum here: viewtopic.php?f=8&t=10740

Good luck!


[quote=“bdgreen”] . . . Good luck! . . . Brian[/quote]Thank you