factory VS Pac-Nor

[Rich]

Loaders and wildcatters,

I made a wildcat from a .220 Swift. The case was blown out like an A.I. but the shoulder was pushed forward leaving about 1/8" neck. Just for grins I paid an extra $20 to have Weatherby radii ground on the reamer.

I ran the reamer into a fresh unfired 12 twist .220 Swift 26" Savage and a 9 twist 30" Pac-Nor on a Remington action. From the same box of ammo I fired some groups. Both produced about the same accuracy .400". The Savage had a 6-24X Tasco and the Pac-Nor had a 6-24X Weaver.

The real difference came from the Ohler 33. Firing 55 Nosler Ballistic Tips the Savage averaged 4,005 feet per second. The Pac-Nor from the same box of ammo averaged an even 4,300 fps.

What made such a huge difference?

[AK-49]

Perhaps the Pac-Nor barrel has smoother rifling and has a slightly smaller diameter resulting in higher pressures and hence great velocities...

[30-338]

Loaders and wildcatters,

I made a wildcat from a .220 Swift. The case was blown out like an A.I. but the shoulder was pushed forward leaving about 1/8" neck. Just for grins I paid an extra $20 to have Weatherby radii ground on the reamer.

I ran the reamer into a fresh unfired 12 twist .220 Swift 26" Savage and a 9 twist 30" Pac-Nor on a Remington action. From the same box of ammo I fired some groups. Both produced about the same accuracy .400". The Savage had a 6-24X Tasco and the Pac-Nor had a 6-24X Weaver.

The real difference came from the Ohler 33. Firing 55 Nosler Ballistic Tips the Savage averaged 4,005 feet per second. The Pac-Nor from the same box of ammo averaged an even 4,300 fps.

What made such a huge difference?


Hard to say the old 220Wby Rocket might have the same case capacity or close to it 50gr bullets 4200fps and 55gr @ 3900/4000fps. I assume you worked up loads what was the comparison on those loads?

[Rich]

30-338,

It's been a few years since I did that blown out .220 Swift. I never compared it to the Weatherby. I think I was using 47 grains of IMR4350.

It was so accuate I would only shoot at a couple 'chuck each time I went out so there would always be breading stock. What a barbarian! Showing compassion so I can kill for a longer period. I bet that would drive the greens nuts.:o:)

[30-338]

Rich, I'm 67 never loss the love for speed. Was shooting 6x284 with 68gr Bergers 4200fps wore out a bunch of barrels did that back in the early 80's. I'm shooting a 223AI,243AI,6RemAI got a nice little 22-250AI. It's fun and it's funny I looked at a 220Wby Rocket years ago. Well good luck

[Hi Ball]

Rich the difference is most likely the condition of the inside of both barrels. One is evidently smoother than the other, which would give less drag on the bullet being shot. :)