“Best” bullets for 257bob AI

DGY

DGY

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Good evening all! I am getting a 257 Robert’s AI, it is not here yet but sometime next week!
Beautiful rifle, double set trigger, good looking wood….
Anyway I was wondering what you guys like for bullets for the Bob, main query will be caribou and smaller( wolf, wolverine).
100gn TTSX, 115gn partiton, 120 grand slam?
What have you used on deer size game that have been working great?
 
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I've had great success with the 117gr btsp interlock. Used in 2506 so nearly the same velocity. It shot well in my rifle and I've dropped deer and wolves with it.
Not sure what bullet winchester grey box uses in the 120gr positive expanding line but it's devastating on deer and black bear when I used factory loads in my rifle
 
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My go-to bullet in a .257 Roberts (not the AI, but close enough) is the Hornady 117 grain BTSP. I've been shooting the same Ruger 77 in that chambering since I bought in in 1980. Despite any reservations about the boat-tail in a conventional bullet encouraging core loss, that bullet has held together every time I've shot something with it, and the bullet has almost always exited out the far side. Expansion has been more than adequate, and kills have been quick and humane.

That same rifle, shooting a 100 grain Nosler Ballistic Tip was an absolute horror. I quickly stopped using that bullet after recovering more than one with the core completely separated from jacket. Ironically, the one time that didn't happen the bullet simply punched through with absolutely no signs of expansion.
 
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DGY said:
Good evening all! I am getting a 257 Robert’s AI, it is not here yet but sometime next week!
Beautiful rifle, double set trigger, good looking wood….
Anyway I was wondering what you guys like for bullets for the Bob, main query will be caribou and smaller( wolf, wolverine).
100gn TTSX, 115gn partiton, 120 grand slam?
What have you used on deer size game that have been working great?
Click to expand...
Min's not an AI, but I like 117gr Game Kings. No complaints at all.
 
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I've killed many big bodied bucks with my 257 Weatherby, using 100 grain Nosler Ballistic Tip. The Nosler Partition has set the standard for the premium bullet, a 100 grain in the 257 cal. will suffice.
 
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If you want something solid then the ttsx in 80 or 100 grain, or the alread mentioned partitions. For varmint bullets I would look at the ballistic tips, but if you’re actually shooting for fur they may be a bit destructive.
 
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DGY said:
Good evening all! I am getting a 257 Robert’s AI, it is not here yet but sometime next week!
Beautiful rifle, double set trigger, good looking wood….
Anyway I was wondering what you guys like for bullets for the Bob, main query will be caribou and smaller( wolf, wolverine).
100gn TTSX, 115gn partiton, 120 grand slam?
What have you used on deer size game that have been working great?
Click to expand...
I had my eye on that same rifle, if it was the Zastava on #######. Glad to see someone here pick it up!
 
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Shot a bear with a 100 tsx from a 257bee. Longest dead run, no blood trail, was still alive when found, minimal wound channel, exiting about size of toonie.

115 NBT whitetail buck, 257 bee. Bang flop. Wound channel football shaped. Exit nearly the size of a fist.

Somewhere in between would likely be a good do all.
 
Jimbobob08 said:
Shot a bear with a 100 tsx from a 257bee. Longest dead run, no blood trail, was still alive when found, minimal wound channel, exiting about size of toonie.

115 NBT whitetail buck, 257 bee. Bang flop. Wound channel football shaped. Exit nearly the size of a fist.

Somewhere in between would likely be a good do all.
Click to expand...
So maybe a 115gr nosler partiton?!?!
 
I mostly shot 100 grain Hornady Interlocks in my 257AI back when I had it; or rather before I shot it out, then rebarrellled it twice in 22/250 and shot those ones out too.


I sure wouldn’t say no to a 100 or 115 grain NBT or 110 Accubond though. Shot tons of those through the very similar 25-06 and the much faster 257 Weatherby
 
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Dogleg said:
I mostly shot 100 grain Hornady Interlocks in my 257AI back when I had it; or rather before I shot it out, then rebarrellled it twice in 22/250 and shot those ones out too.


I sure wouldn’t say no to a 100 or 115 grain NBT or 110 Accubond though. Shot tons of those through the very similar 25-06 and the much faster 257 Weatherby
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Which one was doing best on games? Least meat lost quick kill on let say deer/caribou size game?
 
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DGY said:
Which one was doing best on games? Least meat lost quick kill on let say deer/caribou size game?
Click to expand...
115 NBT and 110 Accubonds are pretty hard to beat on red deer which are caribou sized more or less. I did a 252 animal shoot comparing bullets while I was at it, its sort of hard not to compare them. It was a fun week. Also used 100 grain Swift Scirrocos which are pretty stiff for a lead core and penetration guys would love those. Kill slower though, which is the trade-off. Also used TTSXs on that shoot, and a bigger piece of crap is hard to imagine. Well, if you want things to die somewhere else they might be perfect.
I rate bullets by how fast they kill, if meat damage is a major concern I’d suggest not shooting them in the meat. ;)
 
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Dogleg said:
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115 NBT and 110 Accubonds are pretty hard to beat on red deer which are caribou sized more or less. I did a 252 animal shoot comparing bullets while I was at it, its sort of hard not to compare them. It was a fun week. Also used 100 grain Swift Scirrocos which are pretty stiff for a lead core and penetration guys would love those. Kill slower though, which is the trade-off. Also used TTSXs on that shoot, and a bigger piece of crap is hard to imagine. Well, if you want things to die somewhere else they might be perfect.
I rate bullets by how fast they kill, if meat damage is a major concern I’d suggest not shooting them in the meat. ;)
Click to expand...
Thanks that is good info!
 
I have a 250AI, and am planning working up loads with the 110 gr AccuBond and/or 115 gr Ballistic Tip to see which the rifle prefers.
When I had a 257 Roberts, I was planning on the same thing. (Hope to have another again someday!)
The hope was to use the 110 AB in one and the 115 BT in the other.
For the caribou, I would prefer the bullet with the Sectional Density closer, or over .250 for more reliable penetration. But honestly, as the SD of the AB is .238, I believe the bonded bullet will assist in ensuring the better penetration despite being slightly lower SD. (The on-game performance of all other calibers AB's has been exemplary.)
With your higher velocity, both should work just fine on your intended quarry.

Looking forward to hearing your reports of performance and adventures!
 
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