Use the .2165 slugs to measure. Push some of them through like they are, and also make a few that fit tighter. You'll be able to get a good idea on the difference between the two sizes and the witness marks left on them.
To make them bigger in diameter here's what I do... With them sitting on a hard surface, lightly tap a small nail into the hollow point tip of them with a hammer. It won't take much to get them to grow in diameter a few thousandths with those small slugs.. I do this regularly on a big bore caliber slug with a custom center punch in the hollow point to be able to resize them. You can do the same thing with a small nail and then push them through the barrel easily enough if they aren't expanded too much.
You should be getting those o-rings today or tomorrow.
Also, here's a write-up I did on how I assemble the Evol so I don't slice up the o-ring on the regulator.
Overview of the long post: On the original generation Evol's, to prevent the threads cutting the o-rings upon re-assembly, first install/push the regulator deep down into the air cylinder so the o-ring is just past the threads. Then screw on the air cylinder onto the receiver, ensuring the...
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