Following...
Recent testing myself using .356, .357, .358 semi jacketed and solid copper.
I'm using a Lee bullet sizer in each cal mounted on my Redding T7.
Some slugs (Bullets) have a gas ring design some are smooth wall. Every one tested so far has had a significant loss of fps.
Example 1 (Baseline), 110gr .357 NSA slugs. OAL, .519
900 fps from a TJ 1:26 barrel at 190 bar
Example 2, 110gr .357 Zero Bullet mfg. OAL .476
680 fps from TJ 1:26 barrel at 190 bar
Pressed through sizing die and weighed. Each was a perfect test sample.
I suspect the gas ring on the Zero Bullet may be causing enough blowby to impede consistency for use in an air powered system.
Currently, I've had about a 50/50 ratio of slugs that have cleared the barrel and slugs they have jammed.
I am currently working with 2 different bullet manufactures trying to develop a consistent slug. The wheels on this bus turn really slow.... It's taken a lot of time and effort to persuade these folks to cross the tracks into the possibilities of the high power airgun world.
It's late/early and I've just finished fart'n around my dungeon machine shop. It's nearly Deer season here in Michigan and I'm burning the candle on both ends to keep my short list happy.
If you're interested, I'll continue to post my findings. Or, I'll sit in the shadows and follow along.
FX Impact M3 .35 and Western Airguns Rattler .357 were used in testing outside the provide example data.
Perhaps a single shot, like a Texan would offer varying results due to its bolt design..
I'm going to make a bench mounted test rig this week. I need to locate a source to obtain barrels that are in current production and that are in use in the airgun world. I can easily make a barrel in my shop. But I'm thinking that's not a realistic choice as that's not what is common place. I've never made one.
I'm thinking it can't be that difficult, should be easy. Then again, I thought my ex wife was easy too. I'm still paying for that one.
Cheers!
K9
