110 BA .338 Lapua 250SMK and 250 Lapua Lockbase wildly different POI

[Mikeinfwa]

50 yard scope zeroing:

load 1) 250SMK, Lapua brass, WLRM primers, H4831sc 88 grains

load 2) 250 Lockbase, Lapua brass, WLRM Primers, H4831sc 88 grains

same point of aim with both test loads

Load 1) point of impact 2 inches left of POint of aim

load 2) POI 7 inches left and 5 inches below POA


wow!

[LongRange]

could be a LOT of different things causing that....if you have checked all the usually things...base is tight,scope is tight,action screws are tight ect....then id be willing to bet the baring surface and ogives being different are causing POI shifts.

[stomp442]

Yep its really all about barrel harmonics.

[psharon97]

I have found that even though 2 bullets may be the same weight, doesn't mean they won't have 2 different points of aim. Find out which bullet produces a tighter group, test it at longer range, then go with that one.

[50merc]

What is your OAL to your lands? My savage is about .100 longer than the reloading data says to set it at. Mine measures 3.747. I have found very little data saying set it at 3.700 range. But everything I'm reading says to start out working a load from .020 to .040 off the lands and see what works best. I'm wondering if mine is normal or built on a Friday.