GTA

All Springer/NP/PCP Air Gun Discussion General => Machine Shop Talk & AG Parts Machining => Engineering- Research & Development => Topic started by: AAJSW4750 on February 25, 2022, 07:56:46 AM

Title: On the edge of insight.
Post by: AAJSW4750 on February 25, 2022, 07:56:46 AM

!st Thanks for all the help and insight.

What I am thinking about, I am hoping to buying a metal lathe about 8x32 benchtop unit.

What I want to build is a .172 pcp for shooting lead free ammo for say a 17fireball.

I am thinking a hatsan 17 cal neutron star and a 17 HMR barrel sleeve installed. Hatsan NeutronStar Specs
Max Velocity   1400 fps
Overall Length   43.5"
Buttplate   Adjustable
Function   Repeater
Weight   8.4 lbs
Scopeable   Weaver & 11mm dovetails
Suggested for   Small game hunting/target practice
Caliber   .177" (4.5mm)
Muzzle Energy   37 ft/lbs
Loudness   3-Medium
Barrel Length   23.0"
Shot Capacity   14

The new barrel would have twist rate of about 1 in 9.

Questions Is this a doable idea and would the pcp have the power to shoot and stablize the bullet??
Hatsan NeutronStar Specs
Max Velocity   1400 fps
Overall Length   43.5"
Buttplate   Adjustable
Function   Repeater
Weight   8.4 lbs
Scopeable   Weaver & 11mm dovetails
Suggested for   Small game hunting/target practice
Caliber   .177" (4.5mm)
Muzzle Energy   37 ft/lbs
Loudness   3-Medium
Barrel Length   23.0"
Shot Capacity   14


I have attached a screen shot of a barrel liner for reference.
I hope i have given enough information for you to see whats jumping around in my mind, also any recommendations for a lathe for less then about 1300. USD would be welcome as well thanks for an help available

Title: Re: On the edge of insight.
Post by: AAJSW4750 on February 25, 2022, 09:24:26 AM

Side note this is a screen shot of the potential ammo

Title: Re: On the edge of insight.
Post by: MJP on March 12, 2022, 04:40:32 AM

Not going to work, all you get is a bullet stuck in the barrel.
Powder burner bullets wont work with air unless you use a sabot and bigger barrel.

Too much force required to engrave the rifling on the metal jacketed projectile.

Marko

Title: Re: On the edge of insight.
Post by: Back_Roads on March 12, 2022, 09:32:12 AM

 I bought the NOE bullet mold in the link, Ended up decking the mold and opening it up to .178 to drop a 18.5 gr slug, that will shoot 910 FPS in a Mrod with factory barrel.  https://noebulletmolds.com/site/shop/bullet-moulds/172/172-24-fn-cd5/172-24-fn-cd5-3-cavity-pb/
 [smg id=8113]
 !2 shots at 50 yards, just letting them fly in the wind, after a few sighters.
[smg id=8114]