Keyhole 100gr spitzer .257
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salmonchaser
Ammo Smith
- Dec 13, 2013
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Welcome aboard. Off hand I would say yes, but it depends. 
Cartridge information and bullet would help. My 257 Roberts starts to fall apart with 110 gr. Is really getting interesting with 115 gr and forget 120s. It shoots just dandy with 100 gr accubonds or 80 grain class mono bullets. My mom’s very old Remington worked just dandy with 120 gr.
Do you know what your rifling twist rate is?
Cartridge information and bullet would help. My 257 Roberts starts to fall apart with 110 gr. Is really getting interesting with 115 gr and forget 120s. It shoots just dandy with 100 gr accubonds or 80 grain class mono bullets. My mom’s very old Remington worked just dandy with 120 gr. Do you know what your rifling twist rate is?
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- #3
Don't know the twist, but she would keyhole 117 and 120 lead spitzers.Welcome aboard. Off hand I would say yes, but it depends.
Do you know what your rifling twist rate is?
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- #4
It all depends on a number of things. The twist rate of the rifling, seating depth of the bullet and frankly I don't know what else. I'm goinf to state what I think on twist rate in the barre. According to the Speer manual data, the common twist for the .257 Roberts is 1 in 10" This is what your rifle should have unless it has been given another barrel or the barrel is part of a custom build.
I have two rifles chambered to the Roberts, a Ruger #1 and a Winchester M70 Featherweight. Both rifles are factory stock.
The Ruger has basically only been test with some of the factory ammo that came with the rifle and is very accurate for a strictly stock, Number One. The ammo is the 100 gr. Norma. Strange because Norma doesn't show the .257 Roberts as one of the cartridges they load. The rifle came with six boxes and I have six rounds left from that first box I shot. The rest are unopened. I'm saving them for the #1.
The M70 on the other hand hasn't shot anything worth a damn. Not the 100 gr. or 120 gr. cup and core bullets Sierra 100 gr. and Speer 120 gr. and definitely not the 100 gr. Barnes TSX. There's a funny thing about that TSX bullet and the M70 Featherweights. My son in law bought one and wanted to use the 100 gr. barnes TSX bullet so he left the rifle with me and I easily found a good load in his rifle. He's happier than a clam in warm mud. I worked up to the same load in mine when I first got it and holes scattered all over the target. I tried the 100 gr. Sierra Game King and the 120 gr. Speer Hot Core with the same results. Scattered holes all over the paper. I know the rifle should do better based results from the Ruger and the son in law's gun.
I have another Featherweight in 7x57 that fouled badly. Shot a few rounds into a fairly tight group then scattered the rest all over the paper. I decided to do a fire lapping job on that rifle and after that was done the rifle not only does tight groups but hardly fouls at all. If that hadn't fixed it. I'd have a new barrel on the gun.
I've been saving those last six loose Norma loads to do an accuracy test in the M70, but I want to lap that barrel first. Maybe my ramblings have given you an idea or two. One more thing, they say when switching yo monometal bullets like the TSX/TTSX, one should do a very thorough removal of any current copper fouling from common cup and core bullets. That worked in the son in law's gun but not mine.
Paul B.
I have two rifles chambered to the Roberts, a Ruger #1 and a Winchester M70 Featherweight. Both rifles are factory stock.
The Ruger has basically only been test with some of the factory ammo that came with the rifle and is very accurate for a strictly stock, Number One. The ammo is the 100 gr. Norma. Strange because Norma doesn't show the .257 Roberts as one of the cartridges they load. The rifle came with six boxes and I have six rounds left from that first box I shot. The rest are unopened. I'm saving them for the #1.
The M70 on the other hand hasn't shot anything worth a damn. Not the 100 gr. or 120 gr. cup and core bullets Sierra 100 gr. and Speer 120 gr. and definitely not the 100 gr. Barnes TSX. There's a funny thing about that TSX bullet and the M70 Featherweights. My son in law bought one and wanted to use the 100 gr. barnes TSX bullet so he left the rifle with me and I easily found a good load in his rifle. He's happier than a clam in warm mud. I worked up to the same load in mine when I first got it and holes scattered all over the target. I tried the 100 gr. Sierra Game King and the 120 gr. Speer Hot Core with the same results. Scattered holes all over the paper. I know the rifle should do better based results from the Ruger and the son in law's gun.
I have another Featherweight in 7x57 that fouled badly. Shot a few rounds into a fairly tight group then scattered the rest all over the paper. I decided to do a fire lapping job on that rifle and after that was done the rifle not only does tight groups but hardly fouls at all. If that hadn't fixed it. I'd have a new barrel on the gun.
I've been saving those last six loose Norma loads to do an accuracy test in the M70, but I want to lap that barrel first. Maybe my ramblings have given you an idea or two. One more thing, they say when switching yo monometal bullets like the TSX/TTSX, one should do a very thorough removal of any current copper fouling from common cup and core bullets. That worked in the son in law's gun but not mine.
Paul B.
salmonchaser
Ammo Smith
- Dec 13, 2013
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25/06 has a lot of fans here, surprised you are having difficulty. I”m sure others will check in with their experience soon. Do you have velocities on either your loads?
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- #7
Running 53gr of 4350 for the 90/100 sierra and same for the 100gr Nosler no lead. Sierra book says 3300fps. Story on the barrel. It was a bull blank with an off center bore. I turned it down to a light weight just to get the bore/barrel concentricity correct. No idea what the twist is. I should buckle down and measure it so I can speak to that issue.
- Nov 4, 2004
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Knowing the twist would certainly be helpful. It's common belief that the weight is the determining factor when talking twist rate and stability but it's actually the length of the bullet. Yes heavy bullets are longer but the shape factors into the equation. Sometimes you can get away with a heavy RN bullet over a ptd or tipped bullet.
In your case, the monolithic bullets are lighter so they become longer. That's why you are experiencing stability issues in your 25-06. The typical twist is 1:10 but I'm thinking your twist rate is slower.
JD338
In your case, the monolithic bullets are lighter so they become longer. That's why you are experiencing stability issues in your 25-06. The typical twist is 1:10 but I'm thinking your twist rate is slower.
JD338
filmjunkie4ever
Handloader
- May 4, 2011
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The .25-06 standard twist rate is 1-10” and even if it doesn’t care for the 100 grain mono’s accuracy-wise, the twist is sufficiently fast to not keyhole that bullet. If yours is custom, it is possible that someone put a custom twist (like 1-12” for example) which would not be conducive to the 100 grain monos.
That said, when I got a new barrel put on my Remington 700 .25-06, the smith talked me into a 1-9” twist. So far am happy as can be.
That said, when I got a new barrel put on my Remington 700 .25-06, the smith talked me into a 1-9” twist. So far am happy as can be.
Last edited:
- Nov 4, 2004
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Guy Miner
Master Loader
- Apr 6, 2006
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Welcome aboard!
I suspect that you've got slow-twist rifling. Some .25's have been built with 1:12 and even slower. They work brilliantly with lighter, shorter bullets, but not well at all with longer bullets.
If I'm wrong and rifling isn't the problem I don't have a lot left for solutions... There are some GREAT cup and core 100 gr bullets, and lighter too...
Guy
I suspect that you've got slow-twist rifling. Some .25's have been built with 1:12 and even slower. They work brilliantly with lighter, shorter bullets, but not well at all with longer bullets.
If I'm wrong and rifling isn't the problem I don't have a lot left for solutions... There are some GREAT cup and core 100 gr bullets, and lighter too...
Guy
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- #12
Love the cup and core bullets, but I was trying to go lead free. Had a great presentation by North American Lead Free Partnership at our local gun club. A bit of an eye opener and gave me the impetus to switch to lead free for Deer. Looks like I need to see if Nosler will return my unopened box. Or if any of you folks want to buy a full box and one with 35 bullets, let me know.
RL338
Handloader
- Mar 23, 2017
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Barnes has a 80gr TTSX that should work in a slower twist.
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- #14
Funny, after my last post, I used Mr. Google and found the Barnes bullet. Checked my e-mail and saw your comment! Great minds must think alike
Gonna' try them!
salmonchaser
Ammo Smith
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wvbuckbuster
Handloader
- Nov 5, 2015
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Welcome. As has been stated the twist is what I would be checking first. Use your cleaning rod and mark it. Easily done. There was a range member years ago who had a bench-groundhog rifle built in 257 Ackley with a 1-12 twist as he didn't plan on using it for deer. So, it is possible someone had your barrel twisted slow.
Try lead-free Hammer bullets!
I've been shooting lead-free bullets for several years, tried many different mono bullets and Hammers are at the top. More accurate, easy to find a load for and better terminal performance on game. They act much like a Partition only they are lead free.
Hammers do best light and fast!
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salmonchaser
Ammo Smith
- Dec 13, 2013
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Good luck. Looking forward to seeing your results
