My other thread on the Hornady Superformance really got me wanting to try it so I bought 2 boxes of 53 grain vmax for my 223 and got out to shoot today. Lot cheaper than buying a couple of .270 boxes if it turned out to be a dud.

(Rifle is a Savage 12 action, Heavy 26" barrel, accutrigger, blackhawk picatinny rail, 6 hole blackhawk rings, SWFA SS 10X42 mil quad scope.)

This is a very accurate and easy shooting rifle so I thought it would make a good test platform. I shot off the bench with bipod and rear bag at 100 yards.

Overall I was actually impressed...The accuracy was outstanding - 1st group was 5 shots into .75" second group was 10 shots all within 1.25 inches...Accuracy was awesome in my rifle.

What was a disappointment was velocity claims - the box says 3450 from a 24" barrel. I have a 26" so I was expecting 3500 FPS. However in 20 rounds fired the highest velocity I recorded was 3409 FPS. Most of the rounds shot fell in the 3350-3370 range - 100 fps under advertised specs.

But a 53 grain bullet at 3350 fps that shoots bullets in little tiny groups is just fine for a 400 and in p-dog rifle. Ill be anxious to see how this ammo does in this spring when weather warms up a bit.

Thanks for the write-up.

With minor exceptions, I'd say that's the case with most factory loadings.

I tried the Superformance stuff in 2 .30-06s, it chronoed the same as Remington green box.



P

Super

Hiaring8,

I've written and posted about this numerous times before, but here's one more short version:

Ammunition test barrels are normally SAAMI minimum or close to it, because if they tested ammo in "loose" barrels then it would produce excess pressure in minimum barrels, which can be found on occasional factory rifles but are common on custom rifles. Chamber size, throat length and bore diameter all make a difference.

SAAMI standards also allow for plus or minus 90 fps from nominal velocity in a specific production lot of ammo.

Yet another possibility is your chronograph isn't as accurate as the chronograph used by Hornady, but even more likely is you didn't chronograph at the standard 70-degree temperature. And Superformance powders normally do result in slower velocities in cooler weather.

thank you for reminding me of those facts

Once upon a time I owned two Remington model 7's with 20" barrels, both chambered in 7mm-08. One of the rifles came from the factory with a very tight chamber - it was consistently 200+fps faster than the other rifle with 120's and would sometimes show pressure signs with some factory ammunition.

David