Speed difference between reality and what's on the box

[Mike Matteson]

It is not at all uncommon, often times you can see more than that. An extreme and more rare example, my buddy had a box of federal premium vital shok 165 grain spbt 30-06 ammo, and after a 200 yard zero, was hitting excessively low at 400 yards. I checked his velocity, and he was consistently at 2050 fps. Yes, 2050. Box stated 2800. Pulled three bullets, consistently 56.5 grains of an extruded grain powder, so a roughly appropriate charge of an appropriately selected burn rate powder, I assumed they just used the wrong powder, an excessively slow one. Checked on their site, no ammo recalls, so I called them. They said sorry and sent a free box of ammo.

I have had a couple friends with the hornady precision hunter ammo get above and under on stated velocity, however one consistent thing was that their extreme spread was all pretty big, around 50-80 fps.

That the problem with factory ammo. It's like a box of chocolates. You never know what your are going to get.

 

[Catskills]

With the exception of Weatherby ammo, I've never found factory ammo to be close to advertised velocities. Its not uncommon at all to see 100fps+ differences. I remember a couple that were worse: Federal 270 with 150 partitions at 2715fps, and Winchester 30-06 180s right at 2500fps. Because there are slow and fast barrels, it always pays to check. With the exception of one tight chambered 270wsm, Ive also found loading manual velocities to also be overstated by on average 75 to 100fps. Interestingly, fast barrels also exist. I have a 7mmSTW that regularly shoots 100-150fps faster than advertised velocities. A chronograph is indispensable in my opinion.

 

[jerry moore]

I've had this happen the other way around.

Federal Premium 7mm Rem Mag with 168gr Berger Hybrid Hunter, it's advertised at 2,870 fps and Im getting 3,055 fps. That's a 185 fps difference in my Rem 700 with a 26" barrel.

i find most information in manual is based off 24in barrel

 

[P7M13]

Manufacturers print MV on the box for the design of the cartridge with the given bullet weight, charge weight and powder energy. They don't print MV / ES / SD , and I don't take it as gospel to state that's what the speed will be in my rifle.
Just in lot to lot powder variances, ball-parking a figure, you could see as much as 5% change in MV.

Manufacturer's embellishments are not uncommon. With mass production they can't effectively have a grasp on actual numbers.

Maybe H$M ammo (?) as I have heard many complain about their quality.
You would be implying that ammunition manufacturers don't exercise QA/QC on ammo they produce. I've done automation work at one ammo manufacturer, and they pulled a load from the process every five minutes and shot it through their chronograph to see that it conformed to the load spec. It was not "just some barrel" but a very expensive piece of equipment right there on the manufacturing floor.
I have a colleague who has done extensive QA/QC automation at the LC plant in Kansas. He took a day to explain to me the things they do there -- they were at the extreme end of that business, and their whole purpose was to ensure that 99.9999% of the ammo that goes out of the plant will perform within specification limits.

 

[mntnflyr4fun]

I only tested one round, so not the best conclusion, but that speed input into the ballistic app exactly matched the trajectory at 900yrds. I am in the south hemisphere currently and i have not updated my location.

OP, your question is based on only shooting one round? That could open the door for a ton of different reasons you came up short on speed..... another 5 or 6 downrange to get an average speed might be a bit more telling....

or, in the southern hemisphere, you are upside down and so its possible that you are running 190 fps fast, not slow and just see it differently ...... down under is a different world after all...........

 

[flassen]

Somehow I am beginning to understand the logic of the "down under" comment ;-)

 

[asd9055]

All, keep in mind, the ammo is tested in a "specific" barrel with a certain chamber, barrel length and conditions. Your rifle most likely is different. Resulting in different pressures and velocities.

 

[Tiny Tim]

Shot some factory ammo in my stock Savage 6.5 CM this morning. Same barrel length as advertised on box. running 100-120 FPS slower than advertised. After looking at the atrocious condition of the factory rifling, I'm surprised its not slower than that. LOL Still shot a 3ish inch group at 567 yards

 

[D-mon]

We were shooting east to west. Although only one round went through the chrono , a bit more than a dozen went on the 900 yards target in total and the come ups are consistent with the speed input into the ballistic app.

 

[Swamplord]

Nosler ammo failed to deliver while Barnes did awesome !

 

[lhp63190]

The 143 ELD-X listed box velocity is 2800. It shoots 2667 through my gun (24" Bergera w 8 twist). That said, the ES is single digits which is extremely impressive for factory ammo.