AI AX barrel caliber change zero shift...what are you guys getting?

[dms416]

How much are you guys seeing? Going from 308 (AI/WinTac) to 6.5 CM (AI/WinTac), my 6.5 is a full Mil low at 100y and about 0.3 Mil left. This is about the average as I might be +/- 0.2Mil in any direction in just removing/reinstalling the same barrel.

What are you guys seeing when you swap calibers?

 

[FUNCTIONAL]

You might call me a liar but i had zero shift reinstalling the same barrel. I had to stuff my rifle in a small suitecase and broke it down, reinstalled at the match, torqued, even pulled off the caps to rezero my razor. Fired 5 shots and was dead on. If there was any shift I couldnt tell. Shocked me honestly. Same results every time.

 

[morganlamprecht]

betweem different caliber barrels, about 1-2 mil in either windage or elevation...ive had quite a few over the last couple years...22 creed, couple 6 comps, couple 6.5 creeds, 308, and now im running a 6 slr...the return to zero for all of them is within 0.1 if not spot on...i have the turret settings for all of them and i adjust the turret when i swap barrels, and carry on

 

[Servo93]

AIAT here.
Between my factory 20" 308 and my 24" 6.5 Creedmoor I have a 1.0 mil vertical and a .1 mil horizontal shift.
When I first got my AT the repeatability was absolutely spot on.
Now after about 30-40 swaps it doesn't seem as repeatable but I have never used a torque wrench, just paint marks on where my allen key should line up. My plan is to use a torque wrench from now on to see if that helps. I remember a thread awhile back were Lowlight and a few others said they needed to use 65 lb/ins instead of the recommended 45 to keep things consistent.

 

[morganlamprecht]

AIAT here.
Between my factory 20" 308 and my 24" 6.5 Creedmoor I have a 1.0 mil vertical and a .1 mil horizontal shift.
When I first got my AT the repeatability was absolutely spot on.
Now after about 30-40 swaps it doesn't seem as repeatable but I have never used a torque wrench, just paint marks on where my allen key should line up. My plan is to use a torque wrench from now on to see if that helps. I remember a thread awhile back were Lowlight and a few others said they needed to use 65 lb/ins instead of the recommended 45 to keep things consistent.

myself and a buddy were 2 in that thread who upped the torque to 65 after we saw some consistency issues...between the handful of barrels i run and swap them multiple times monthly, im probably over 200 barrel swaps in the last couple years...some range trips i swap 3 or 4 barrels in a day to verify all the dope in 1 trip...no issues with RTZ yet since upping the torque

 

[Servo93]

Good to know! Thanks Morgan

 

[samb300]

myself and a buddy were 2 in that thread who upped the torque to 65 after we saw some consistency issues...between the handful of barrels i run and swap them multiple times monthly, im probably over 200 barrel swaps in the last couple years...some range trips i swap 3 or 4 barrels in a day to verify all the dope in 1 trip...no issues with RTZ yet since upping the torque

Morgan - have you tried getting a new screw for the QuikLok mechanism? I know you're having good luck with 65 in-lbs, but the torque at which that M5 screw begins to stretch is around that point. Maybe your original screw is stretched and that's why you need more torque than recommended? Just a thought.

 

[morganlamprecht]

Morgan - have you tried getting a new screw for the QuikLok mechanism? I know you're having good luck with 65 in-lbs, but the torque at which that M5 screw begins to stretch is around that point. Maybe your original screw is stretched and that's why you need more torque than recommended? Just a thought.

Nah I haven't, I originally used 49 in lbs until I started having my zero wander a bit then I upped it and forgot about it

 

[Primus]

I know fastners stretch over time. I wonder if the barrel nut/lockup of some of these switch barrel systems stretches over time so you would not be able to just turn the nut to a notch. You would need to use a torque wrench to get it to where it needs to be?

 

[beenjammin]

I set a fat wrench to 50 and it has worked like a champ. I go from .308, to .260, to 6.5CM all in the same match between relays.