350 Mag opened up - horrible piston seal condition

[Toxylon]

Quite a few guys have converted their 350 Mags into .25 cals and been very happy with the result. The modded .25 cals shoot around 220 m/s and 33 J. That's my goal, as well.

When I was researching my options for a reasonable .25 cal springer, it pretty quickly boiled down to a handful of contenders: the venerable Webley Patriot, the Hatsan 125 & 135, and a converted 350 Mag. After reading about serious QC issues with the Turkish Patriots and opting for a quality product, I sprung (heh) for a used 350 Mag in the useless .177 cal, and contacted Mike Melick for a .25 cal replacement barrel.

As it turned out, my little-used Mag needed instant replacement of the piston seal, which took a really long while in these quarantine times. Only last week or so I had a working gun in hand, and could put it to the test. At any rate, I have no use for another .22 cal, and will go the .25 cal route, no matter what.

[EricFR]

Interesting this .25 cal barrel, is it Mike Melick from Flying Dragon Air Rifles?

[Toxylon]

Interesting this .25 cal barrel, is it Mike Melick from Flying Dragon Air Rifles?

Yep.

[dtdtdtdt]

Somewhat aside but, I think relevant to the Power developed by various power plants and pellets. 

I tested over 80 .177 pellets in over 100 individual tests to include calculated power from pellet weight and velocity actually measured in my Diana 54.  The overall average was about 18fpe with only a couple not being within 1fpe for pellets from 4.1gr to 13+. Power is a result of the power plant's native output.  I also did it with my FWB300 and found an overall average of just under 6fpe. 

Higher power requires the heavier springs.  I'm not expert in springs so will stop there.

Dave

[EricFR]

I'm already on the affair to receive such a barrel from a Xisico B28. Thanks for the tip Ilimakko.
Dtdtdtdt, yes it's the combination of spring power but also, pellet caliber and weight, barrel length and swept volume. This also affects the piston weight and recoil so it looks more and more like a running IH Titan. Hahahaha
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