Scirroco tumble?

Went to the range yesterday to try yet again to get my new, bought it from PSTLNTR, barrel to shoot. It is a 15" full bull Bullberry Encore in 240 Weatherby. I really want to shoot something in the 85 - 90 grain weight. Tried Barnes X, Nosler Accubond and lastly Swift Scirroco. This barrel keyholes everyone of them with all types of powder charges. I mostly use Hogden powder from light to strong and from really slow to fast burn powders. I'm confussed! Anybody have any thoughts that may help? I know the 240 WBY is a rare bird, but the 243 caliber is not and maybe there's some collective wisdom to be tapped here. Help!!!
I've ordered some 100 grainers and even the Barnes Original at 115 grain, but it probably won't shoot them either, just got to try.

The only time I've had bullets keyhole was when I wasn't pushing them fast enough. Are you shooting light loads?

sounds like twist rate try to see what twist rate the barrel has. if it's too slow, it may not stabilize heavier, longer bullets.
what ya wantin to hunt with it? may have to try some lighter weights 80gr and less......or keep tryin others to seeif one will shoot. how about 80gr and 90gr nosler bt's?....or an 85gr nosler partition......or maybe even better yet a sierra 85gr hpbt. the sierra 85gr hpbt has a good deer/varmint reputation.
keep us informed

I agree with Kyle {Did I say that out loud}. I had a Striker in 243 Win that would refuse to group 95 gr.Balistic Tips. I mean about 8" patterns at 25 yards. I dropped down to 80 gr. Sierra and the groups dropped down to about 1" at 100 yards.

The twist of your barrel may be wronge for the heaver bullets but could work great for the lighter ones.

Another thing to check is the crown. A ding in that area could possibly cause alot of problems.

Jeff

i tried 100 gr. ballistic tips in my 257 last year and it looked like the target was shot with a shotgun(full choke of course)but nothing to brag about!put the 90 gr.sierras in it and the accuracy was back,now i have been tinkering with 85 gr. ballistic silvertips and it likes them also.i have some federal 120 gr.partition factory loads that i need to try just for curiosity.did the previous owner recomend any loads?jim257

i heard that! .....lone eagle agrees with me

gary has an excellent point also. even if the twist is right, and the velocity is not high enough, then they may not fully stabilize.
in a couple small case 6mm's i've had with 12" twist, they seemed to be harder to find a good load for, even though the twist shoulda worked ok. i seem to have better luck with 10" twist in a 6mm pistol barrel.

I was think I'd try to check the twist. If I remember right, just mark a cleaning rod and measure how far I push it through the barrel to make one revolution. I tried speeding up the bullets on the Scirroco, didn't seem to help. I was using H380, thought I might go to slower powder and maybe use magnum primers. For some reason Hogden doesn't recommend magnum primers for this cartridge.

in the .243win faster than usual powders give good accuracy in pistol length barrels. IMR4198,RL-7, and AA2015 come to mind right off. if ya can find data to get started with those, that might be an option to look at.

if ya don't have one.....a chronograph is extremely valuable in working up loads. less than $100 too. sure does tell ya a lot of good stuff. if ya get excess velocity, over whats shown in manual data, it's possible you're "too hot". if ya get low velocity.....maybe you're not gonna get the performance you want, or need out of certain bullets.