Why doesn't FX "do" .177 as well as the other calibers(.22, .25, .30)

[bowopt]

I would LOVE for FX to come out with a 700mm .177 slug liner! I had to machine an Alfa Precision barrel to shoot the slugs I want out of my Maverick. The extra couple of inches sure would be nice to have for the 20+ grain slug varieties. The AP barrel is a laser with the Griffin 22 grain slugs, but I haven't tested it yet with the new NSA 20.5 grain slugs. My Maverick can make over 50 fpe in .177, so a 700mm .177 slug liner would be SWEET for slinging some 23/24 grain slugs! I have another AP barrel that does well with those, but I'm hesitant to machine it for the Maverick, since it is 16mm OD, and will add quite a bit of weight to the gun. The other AP barrel I did machine is 15mm OD and still adds quite a bit of weight to the gun at 25" long. A 700mm liner sure would solve some problems for me at least!

My fx dreamline 177 with 600mm barrel is otw. I have a 700mm slug barrel and 2 plenums and i will install them.

I want to shoot slug with good shot count, at least 2 mags.

You mentioned that you might be shooting 20.5 gr NSA. May I know what's the reg pressure you are at and the result shooting thr 20.5gr NSA or 20gr zan? And the poop count as well?