Multi-Caliber system POI shift experience, what do you get?

[Rasyad]

I posted this question in the gas gun section but figured you folks might have more data for me. Switching barrels on your Multi-caliber rifles, what is the POI shift you see at 100 yards? It would be great if you could also post which rifles, barrel length, and calibers you are shooting.

Starting off....With my LMT MWS, I am getting a consistent 7.25" between a 13.5" 308 barrel shooting 175gr FGMM and a 20" 6.5cm shooting 140 gr Hornady ELD match. Oddly, the 6.5 is shooting lower on the target. Both barrels are shooting MOA or better depending on me. While I may have a problem, possibly of my own creation, I don't consider this a warranty issue and LMT is being great.

I understand there are several ways to manage zero between the barrels.

However, at this point I am simply trying to figure out the range of typical POI shift folks are seeing. I really appreciate any data and thoughts you folks can offer.

Thanks,

Rasyad

 

[kthomas]

Though not a "switch barrel" rifle per some peoples definition, I switch shouldered barrels on my Mausingfield build routinely. Less than a 0.10 mil shift.

Barrels are 28" heavy varmint in 6BRA, and 24" MTU in 6.5 Creedmoor. If you want consistency, I don't think you can beat shouldered barrels.

 

[Nortex]

I have a surgeon 591 that I routinely swap barrels on between 223ai, 22 creed, 6 creed and 7mm-08ai. A few tenths is about all I ever get in variance between all barrels. It's not a switch lug or anything fancy. I pull the scope and leave action in the stock when swapping barrels.

 

[LeadZeke]

6.5CM to 308 and only ~1in at 100y. But that is also a 24in barrel to a 16in barrel.

 

[Rasyad]

Thanks for the information. This is the range of POI shift I thought I should be getting and motivates me to get my rifle sorted out.

Rasyad

 

[mgrs]

Barrett MRAD. Shift is entirely repeatable, but can be substantial moving across barrels. For example, the shift in the below case was something like 1.1 mil left and .7 mil up going from .260 to .338. A .308 barrel, on the other hand, showed less than .2 mil shift from the .338 POI.


100yards, factory prime ammunition, which is normally around 1moa for 5-round groups at this distance. Procedure:

shoot 3 rounds .260
replace .260 barrel with .338
shoot three rounds .338
replace .338 with .260
shoot three rounds .260
remove and replace .260 barrel
shoot three rounds .260

The resulting .260 group. I did call the flier in this case and did not measure it as I do not think it can be attributed to the weapon:

 

[deersniper]

Desert tech covert. About 1/2 Moa down switching to 223 to 308. From 308 to 6.5 is about 2 Moa up.

Haven't messed with my AIAX enough to to document it but i hear it's a lot more than the Dt

 

[mark5pt56]

Going by memory on the AT, 6.5cm/.308 .1 E/.2W. I sold th .308 barrel and here a couple years later want to get another.

 

[Sniperstud]

AI AXMC zeroed at 100 yards with a 20” SS .308 barrel using Hornady 168gr AMAX TAP. Switching to a 26” SS 6.5 CM barrel, using Hornady 147gr ELD-Match TAP, produces a 1.0 mil shift to the left, with no shift in elevation. Switching to a 24” SS 300 WM barrel, using Hornady 178gr ELD-Match, produces a .2 mil positive shift in elevation, with no shift in windage. All shifts have been verified as consistent and repeatable.

 

[Rasyad]

Great information and strategy for managing the zero offset.

I have been toying with the idea of zeroing the scope for the 20" 6.5 cm for precision shooting and longer distance. For the 308 I would use maximum point blank distance for a 4" target out to 205 yards, and hold over beyond that. Switching from the 6.5 cm barrel to the 308 I could simply dial the MPBR setting then lock and ignore the turrets until I go back to the 6.5 cm.

Of course, my other thought is to zero the scope for the 6.5 cm and call it done (matched scope and barrel). Switching to the 308 I would also switch to a red dot set up for MPBR.

Rasyad

 

[SRPowah]

My SRS shift is small enough that I can't tell the difference at 100 yards. Still shoots sub-moa consistently.