Not the most accurate sniper rifle but general issue rifle...
Such as:
Springfield 03, 03A3
Enfield P14, P17
Mauser 98 (Man....just name some version)
Mannlicher (Man, just name some version)
Enfield No. # whatever
Arisaka
K-31 (a ringer?)
Well, you guys get the idea. I'm sure the sights have a huge impact. I have an Enfield Ishapore 2A1 in 308 that was hopeless...untill I maneged to come up with a Parker Hale PH5A. Boy did that change where the holes in the target were.
So you can change the sights within reason (no scopes) and do your favorite handloads but that's it. Which rifle makes the most holes in the 10 ring?