Short barreled .257AI

[MT Pockets]

I am having a rifle rebarreled in a .257 Roberts AI. Mine will have 7.5 twist and be 20 inches in length. I am new to loading for the Roberts and the AI version and want to ask if leaning toward faster powders would be an advantage with the shorter tube. With powders being harder to find nowadays I want to maximize my time spent loading to prepare for 2026 deer season. I want to load bullets in the 110gr to 120gr. range. Anyone with experience with a shorter barreled Roberts AI?

 

[SJB358]

The slower powders will work best for that, no matter the barrel length if you want the most speed.

Sounds like a killer rifle.

 

[xphunter]

Just use regular powders for long barrels.
I don't always use The Slowest Powder, but sometimes I will use one just a tad faster then the slowest.
Example: 15-18" 6.5-284 I typically use H-4350, but I have also used H-4831sc