20.2 Nielsens accuracy in FX 700MM superior liner - question for experts and headsize experts

[Maizen]

Has anyone found a sweet spot for the 20.2 Nielsens in the superior liners? Is it viable to push them to 1000-1100 FPS? Ted from Tedsholdover is able to push 31.2 grains Nielsen slugs at 1100 FPS with very good results (sub MOA). I’m trying to match that but with 20.2 grains. Can someone explain it using science? Let me know. Thanks.

What about head size? What is the best head size for the superior liner? Ted was using .2165 in his.

 

[madeintheuk]

I shoot them at 930 from my crown. Above that they started to destabilize, but that could just be the crown running out of steam. I’m running a 380 barrel on mine, so the shot cycle needs to be snappy, or the wasted air becomes unstable.

 

[Healthservices]

Wasn't Ted using a 800mm liner?

Allen

 

[M0ist0ne]

980 was where I was loving the 20 grainers, but out of a 500mm. Little laser gun

 

[TDK]

20.2gr and 31.2gr are very different (and your gun is probably different from Teds as well) so I wouldn't count on duplicating his results. The 20.2s will probably shoot better in the 1:24 Superior standard liner, but you never know, they might shoot out of a Heavy Liner. Most people seem to have success in the 900's, but that doesn't mean it can't work in the 1000s. You'll just have to try. That was the biggest takeaway from Ted's video - you never know what is going to happen. Shooting a 31gr slug out of a near maxed out gun, at 1100fps (faster than match rimfire ammo!) and having excellent accuracy? Few would have predicted that.

With regard to diameter - most FX barrels tend to like .217-218 range, but once again, you just have to try, and your barrel may like .216. I was shooting 20.2s out of my 600mm at 965fps for about a year and then lost accuracy. I think the slugs may have changed, but can't be sure. I'm having to start over and run through different slugs and tuning again to see if I can get to the bottom of it.

With slugs, expect a lot of experimentation.

 

[Maizen]

980 was where I was loving the 20 grainers, but out of a 500mm. Little laser gun

What was your reg at?

 

[Jlowe]

In my Maverick Sniper, 950fps and above worked well with the .217 size and the Daystate version, which I think is the .217 size, but it doesn't say on the label. I hunted squirrels with them last fall at 980fps.

 

[M0ist0ne]

What was your reg at?

140bar if I remember correctly.