AIAE MK III .260 Jumping the Grand Canyon

[tnichols]

My AE now has 175 rounds through it shooting Copper Creek "factory" ammo. It's crazy accurate, no complaints. I'm getting ready to reload for this rifle now and measured the chamber with a Hornady/Stoney Point gauge today. Long story short, with ammo loaded at OAL of 2.800, those bullets are jumping 0.147! I'm curious why they (AINA) are running so much free bore. Any ideas or have any of you had/noticed this much free bore in your own rifles? Thanks.

 

[Temp9]

With what bullet? My MKIII touches the lands at around 2.830" with 175gr SMK's, so only .030" of jump at 2.800". Most of your tangent ogive bullets won't mind the jump too much, but that seems like an awful lot of jump for an AI.

 

[tnichols]

That's what I thought. The load I'm shooting and almost out of :-( is the 142 smk. I've only shot a few of groups with this rifle, but the ones I have, run consistently at .3-.4 MOA. I've having to switch to the 139 Scenar due to the non-existence of the 142's, and I'm wondering if that bullet will tolerate that much jump. Guess I'll shoot 'em and see.