Will a pillar and bed job reduce POI between loads?

[Corn-Picker]

I understand that each rifle is an individual, but generally speaking, will a pillar and bed job reduce POI between different loads?

I have a CZ 527 carbine in 7.62x39 that I really like. It's reasonably accurate with a scope, about 1.5 MOA with the best ammos. But, there's a huge POI variation between loads. Extreme spread between loads is over six inches at 100 yards. I have open sights on this rifle, so adjusting the POI between loads is not as trivial as it would be with a scope. What's particularly annoying is that the biggest spread is between my preferred hunting ammo (Double Tap at $2/cartridge) and my preferred plinking ammo (Wolf steel cased at $0.25/cartridge). Both of these ammos shoot relatively good groups, it's just that the two tight groups are six plus inches from each other.

Is this type of POI variation generally a bigger problem with thinner barrels? The CZ carbine is a "zero" contour, it's the thinnest barrel on anything I own.

 

[Averageman]

It's possible, but not very likely.
Bedding the rifle might tighten up your groups, it's not however likely to effect the wide variations in your zero between two different ammunitions.

 

[Lafitte]

You may be able to close the POI difference by studying the external ballistics of different ammo and selecting two with similar ballistics. I doubt that pillars and bedding would make much difference

Lafitte

 

[jmr40]

No. You are shooting completely different ammo, it would be rare for it to have the same POI. What you are seeing is perfectly normal for any rifle. You might be able to find another practice ammo that is closer to the same POI, but I wouldn't expect it to be the same.

 

[RX-79G]

Are you shooting all .311 surplus type ammo, or are you also shooting US .308 caliber brass loads?

 

[Corn-Picker]

A mix of steel cased and brass cased, all shooting 0.311 bullets (some copper, some FMJ, some round nose). All of my rifles have variable POI with different ammos to some extent, but the CZ to a much greater degree. I see maybe 2-3" POI variation with various ammo in my 223 and 308, and about twice that with the CZ.

 

[Taurus 617 CCW]

Depending on several factors your gun may be having POI swings from different bullet ogives. Not sure what the shapes are of the bullets you listed but I know some rifles prefer a secant ogive and some prefer tangent. The secant ogive is a longer taper like the Hornady bullets. The tangent ogive is more football shaped. Nosler bullets uses this type of ogive. Other factors that can affect POI are velocity, rifling type, and twist rate. You might experiment with some other types of ammo to see if there is a trend.