Hornady sst inconsistencies

[YoungGun96]

I was recently shooting some 130gr factory superformance sst's through my ruger no1 in 270win at the range. Shot average, about 1" at 100 yards. Ammo was purchased about 3 years ago. Realized I was running low and bought a new box. This new box shoots 5+" at 100 yards. Has anyone ever had this happen before? (tried the gun with other ammo and was clover leafing at 100 yards)

 

[Ganderite]

The factory stamps a lot # on each package.

The 270Win 130 gr they made in 2011 would not necessarily be the same recipe as what they loaded 4 years later. In effect, one could be 4350 and the other 4831.

A handloader would try different loads and make note of which one shot the best.

A non-loader using factory ammo would try different ammunition and find out which one shot best in his rifle - AND THEN BUY A GOOD SUPPLY OF THAT SAME LOT #.

I used to work in a big ammo factory. When the day came to switch the machines over to a new caliber (say 270) we would check the powder magazine to see what powder we had on hand in sufficient quantity. Typically there are at least 3 suitable powders for each caliber to choose from. My job was to find the powder charge required with that particular lot of powder to reach the specified velocity.