Tf did I buy?

[Jsc5150]

This was labelled as “CMI Part” for $15, couldn’t resist.

I hoped it would be a crappy reg, but looks more like an expansion chamber, or an attempt at one.

The baffled interior and finned exterior are unlike anything else I’ve seen before, like a machinist desperately wanted to shoot co2 in freezing temperatures

[scottieb]

That is an old school expansion chamber.

[Siress]

...because a machinist in the northern climates desperately wanted to shoot CO₂ in the winter before availability of HPA.

[RuleOfSines]

I like these for their aesthetics, I had one in the package somewhere, forget what the brand was. I think it had a fox on the packaging

[Chappy]

Kinda like when some crazy engineer designed the blowback because he desperately wanted a semi auto without batteries. Silliness…

[Ecapnation]

In line expansion chamber... Ancient technology

[Jsc5150]

Damn dirty deletes lol

[MrBarraclough]

Old inline expansion chamber. Even has external heat sink fins.