25 cal question...
- Thread starter tuffteddyb
- Start date
Get a rifle with a tighter twist rate.
Many of the older 25 cal rifles will have 1-14 twist rates, and even some of the new and custom barrels have that twist.
1-10 twist rates will stabilize most cup and core type bulets. Monolithic bullets will require a tighter twist, say around 1-8 with heavy bullets.
I have a good friend with a 25-06, who shoots monolithics, it's a Remington 700, with a custom trigger and a 1-8 twist Shilen barrel. Shoots heavy bullets well, but not great for bullets under 100grains.
Many of the older 25 cal rifles will have 1-14 twist rates, and even some of the new and custom barrels have that twist.
1-10 twist rates will stabilize most cup and core type bulets. Monolithic bullets will require a tighter twist, say around 1-8 with heavy bullets.
I have a good friend with a 25-06, who shoots monolithics, it's a Remington 700, with a custom trigger and a 1-8 twist Shilen barrel. Shoots heavy bullets well, but not great for bullets under 100grains.
Yup 
buy or build a 25 CM or 25 RPM 
buy or build a 25 CM or 25 RPM 
- Location
- AB foothills
A 257 Bob !
Be neat in 20 inch or so , deer round .
257 Roberts , but I like old school..
I was going to sell my Kimber 84m Montana in 257 Bob but can’t, such a sweet little rifle. Deadly with 100g TSX’s.
There is a reason your cartridge has a 1-10 twist, (as most are in the 25-06), similar to other cartridges. It's a catch-all twist, meaning that it will accept a certain bullet weight over others. Other 26-06 rifles may perfer the heavier bullets, such as, the 115 or 120 grain.
I recently had a custom rifle built in the 25-06, with a 1-10 twist. I'm wishfull that it will embrace the 100 grain bullets. I will not find-out unttil January 2027, when ideal conditions are similar to November temperatures, for handload development.
Come to Aus one day an we'll try lose it in a creek or river somewhere...
Il get ya back home
257 STW. Like the bee on steroids. - dan
If you decide to build a 257 Roberts for something different, start with at least a 1:9 twist barrel on a long action, if wanting to stick with your 115-117 gr bullets. (Many found that going to the slightly faster twist solved their problems with bullets heavier than 100 gr. While some performed well with them, other had issues.)
My 257 Bob isn't showing great results with the 115 gr BT as yet, but the Sako 591 mag box is pretty short, and I cannot seat out near the lands. Will try the 115 gr Partition to see if the flat based bullet performs better in my rifle. It does like Nosler's 110 gr AccuBond ammo.
Should you decide that you may want to play with the newer, heavier bullets, then you'll want a 1:7.5 twist for up to about the 120-128 gr bullets, and a 1:7 twist for the 133-138 gr bullets. At least this is the info that I have found as I look for data for my new 25 Creedmoor. (24" Benchmark 5R SS barrel with a 1:7.5 twist. My gunsmith believes that it should shoot the new Sierra 131 gr TGK just fine too.)
Another interesting cartridge that is in the works according to one gun writer today, is the 257 AI (Improved). I am doing the research as this is intriguing to me and a project I am planning to do for next year. This should perform right in between the 25 CM and 25 RPM.
Hope this helps!
Best of luck in your quest!
My 257 Bob isn't showing great results with the 115 gr BT as yet, but the Sako 591 mag box is pretty short, and I cannot seat out near the lands. Will try the 115 gr Partition to see if the flat based bullet performs better in my rifle. It does like Nosler's 110 gr AccuBond ammo.
Should you decide that you may want to play with the newer, heavier bullets, then you'll want a 1:7.5 twist for up to about the 120-128 gr bullets, and a 1:7 twist for the 133-138 gr bullets. At least this is the info that I have found as I look for data for my new 25 Creedmoor. (24" Benchmark 5R SS barrel with a 1:7.5 twist. My gunsmith believes that it should shoot the new Sierra 131 gr TGK just fine too.)
Another interesting cartridge that is in the works according to one gun writer today, is the 257 AI (Improved). I am doing the research as this is intriguing to me and a project I am planning to do for next year. This should perform right in between the 25 CM and 25 RPM.
Hope this helps!
Best of luck in your quest!
