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View Full Version : Poly vs. traditional rifling



Nomojo65
11-01-2018, 11:05 PM
I have a Theory?, I know most prefer lw-poly for score with heavy pellets etc. I am assuming because of less drift in wind?, but even though there might be less drift (poly)or even spin drift if that applies in pellets @ their velocities, but I truly believe the drift (because of this impression) that traditionally rifled barrels impart on their projectile is more predictable and maybe even fewer fliers? Iíve been comparing the two barrels w/ 13.4 jsbís, just early observations! Now one variable(of many)that I canít account for is twist rate of the two barrels? Any thoughts? Or should I just shut up and practice...

blades
11-02-2018, 02:16 PM
can't reply to pros/cons of poly barrels not having one - pellet drift-mass vs velocity vs distance - the pellets do spiral in their trajectory, this over and above the spin from what ever type of rifling - caused by the rifling? gut says yes, i do not have anything to back that up. with out digging into artillery theory i would guess those projectiles exhibit the same as well as any other projectile with an imparted spin. there were some treatises on this a few years back -how much of that is still around i do not know after all the hacking around that time. it was on the yellow forum most of that is gone. might still be some on the delphi forums about building air guns. poly barrels in air or any guns really goes all the way back to the 1800's and Mr Whitworth.

Nomojo65
11-03-2018, 08:20 PM
I know I am a novice to airgun benchrest, but just trying to come up with my own experiences, theories etc. thatís how I learn by doing! But Iím not always very scientific or truly eliminate all variables? I have nothing against any design, material or manufacturers, if it works Iím all for it!

Rich De
11-04-2018, 09:56 PM
BTW, what ever happened to the Yellow Forum? I used to read and post on it but then sort of got away from the air gun for a bit and now its gone?

blades
11-05-2018, 12:21 PM
i believe it changed owner ship- don't remember the details after that. Airgun Warriors is the new sight or there is GTA