freddiej
Well-Known Member
I understand the confusion here with the 277 Fury. If I had not had the experiences, mentoring, and read so many articles on ballistics I would be confused about the 1:7" twist choice for the Fury. I will ask this, what is the twist rate of the barrels that shoot the 5.56NATO, 55 grain slugs the best at 1,000 yards?
The answer is 1:7" shoots the 55 grain 223 best at 1,000 yards. the military tested it out and came up with the 1:7" was king of shooting the long yardages with the 55 grain projos. the physics behind it are these as I have read it and experienced it myself. the slower the slug goes the faster the twist rate needs to be to stabilize it. all sub-sonic 30 calibers are 1:7" twist rates. now when the 55 grain .224" projo is going from super to sub sonic out there it needs to be spinning faster to keep it stabilized. the same thing can be said for the 277 fury. if you go long yardage with a 90 through 135 grain slug, it should be spinning faster to keep it stable. I have been advocating for faster twist factory rifle barels for 25 or more years. I have found in my own experience that faster twist barrels for longer yardage hunting, shooting and target are superior. that is why when I had a good hunting rifle made back in 2002; I had the wildcat barreled with a 1:7" twist over the standard 1:10" the 270 winchesters and 270 weatherby's were saddled with. I can tell you this for a fact, the 140 and 150 grain Barnes slugs flew straighter & farther than I ever expected. the 160 grain Barnes originals flew so much better, the Hornady 150 grain SST slugs were far more effective at distance, and no VLD slug was off my list of projos I could shoot.
My old 300 Win Mag got a new 1:8" twist barrel and even though it was an ER Shaw, I put it on myself with a bit of help from a standard piece of brass for a gauge; the 1:8" ER Shaw barrel shot 190 grain Berger VLD's so much better than my 1:10" barrel. Until that year I thought that just because it was rated for the weight/length of slug it was the best. I was very wrong.
things like "Marginal stabilization" came up in calculations, "insufficient twist for stabilizing this slug" came up in computer models of interior and exterior ballistic programs. I was not ammused by this.. then I tested it all out in the real world.. I took a friends 1:8" 300 win mag, my own in 1:10" and shot the same exact loads (190 grain Sierra Match Kings, 68.2 grains of H-1000 powder, prepped Lapua brass, magnum Federal Match Large Rifle primers). My friend's 1:8" twist barrel just shot the 190 grain slugs better than my 1:10" even though the 1:10" tecnically is rated it was so marginal that if it slowed 300 FPS the slug destabilized. the problem I had suffered through was insuffient twist of my barrel. now it is my opinion that if you go faster on the twist, you can not go wrong.
The answer is 1:7" shoots the 55 grain 223 best at 1,000 yards. the military tested it out and came up with the 1:7" was king of shooting the long yardages with the 55 grain projos. the physics behind it are these as I have read it and experienced it myself. the slower the slug goes the faster the twist rate needs to be to stabilize it. all sub-sonic 30 calibers are 1:7" twist rates. now when the 55 grain .224" projo is going from super to sub sonic out there it needs to be spinning faster to keep it stabilized. the same thing can be said for the 277 fury. if you go long yardage with a 90 through 135 grain slug, it should be spinning faster to keep it stable. I have been advocating for faster twist factory rifle barels for 25 or more years. I have found in my own experience that faster twist barrels for longer yardage hunting, shooting and target are superior. that is why when I had a good hunting rifle made back in 2002; I had the wildcat barreled with a 1:7" twist over the standard 1:10" the 270 winchesters and 270 weatherby's were saddled with. I can tell you this for a fact, the 140 and 150 grain Barnes slugs flew straighter & farther than I ever expected. the 160 grain Barnes originals flew so much better, the Hornady 150 grain SST slugs were far more effective at distance, and no VLD slug was off my list of projos I could shoot.
My old 300 Win Mag got a new 1:8" twist barrel and even though it was an ER Shaw, I put it on myself with a bit of help from a standard piece of brass for a gauge; the 1:8" ER Shaw barrel shot 190 grain Berger VLD's so much better than my 1:10" barrel. Until that year I thought that just because it was rated for the weight/length of slug it was the best. I was very wrong.
things like "Marginal stabilization" came up in calculations, "insufficient twist for stabilizing this slug" came up in computer models of interior and exterior ballistic programs. I was not ammused by this.. then I tested it all out in the real world.. I took a friends 1:8" 300 win mag, my own in 1:10" and shot the same exact loads (190 grain Sierra Match Kings, 68.2 grains of H-1000 powder, prepped Lapua brass, magnum Federal Match Large Rifle primers). My friend's 1:8" twist barrel just shot the 190 grain slugs better than my 1:10" even though the 1:10" tecnically is rated it was so marginal that if it slowed 300 FPS the slug destabilized. the problem I had suffered through was insuffient twist of my barrel. now it is my opinion that if you go faster on the twist, you can not go wrong.
