Ammo brand and grain really does affect impact and groupings

[lionking]

I know most of you already know about this, but it is only in the last 10 years I started testing different ammo and brands on paper, before that I was more a casual shooter.

Amazing to me how ammo from the same brand but different grain , or same grain but different brand not only effects size of groupings, but actual impact area also.

Case in point Saturday I tested Fiocchi .32 auto ammo in my CZ 50, all other brands shot groups 1 to 2 o'clock of bulls, Fiocchi shoots dead center bulls. Same with Fiocchi .40 s&w shoots higher and closer to bulls in my Glock 23 while all other brands shoot low and right of bulls.

I know you reloaders take it to another level but now I realize why I might have missed that soda can shooting casual in the woods back when I was more of a plinker lol might not have been me or the gun but the ammo.

 

[bfoosh006]

Yup... always surprises me with the differences... just goes to show, there is more to ammo then the box shows.
Velocity, etc...

 

[Bama59]

LGS here had great prices on ammo bought from Gander Mountain when they closed . I bought several hundred rounds of 9mm 124 gr and 147 gr and found out how different grains performed. Brands are different also, Sellier& Belloit I shot the other day seemed a little hotter than others.

 

[cheygriz]

Grains is a measure of weight. Different weight bullets will have a different POI.

Different manufacturers load to different pressures. (all within SAAMI specs, of course) this will effect POI.

Different "Lot" numbers of the same ammo will often have a different powder or charge and shoot to a different POI.

 

[caribou]

Thats why I used to and soon will be , buying the type of ammo that ''works best'' by th ecase or 1,000 round lot.
That was 1/2 the fun of owning a Finn Mosin back in the late 80's, an M-28/30 for 90$ and a case of Chinese copper washed on strippers in 1,440 round cases divided in two cans, landed here for 89$.

The great thing was that the Chinese was pretty consitant. Later Cheap Czeck BXN (Seilor/Ballot) cases of 54r in 800 rd cases was 60'S in the early 2000's.....Russian and former soviet block countries emptied their stored surplus, and I dont think they have much left to sell us nowdays.....

Oh to have cheap, plentyfull milsurp ammo again..........

 

[ontarget]

Even among premium factory loadings of the same weight and similar bullet design there can be a huge difference. I get 3" groups from my Howa .223 with Hornady match ammo but it will consistently hold under 1" with Federal GMM of the same 73gn weight. And these are always 5 shot groups.

 

[Archie]

This is the alternative for those who do not reload. As noted, not all factory ammo shoots (functions or groups) the same. So test out a selection and see which one fits one's purpose. Buy as much of the 'best' one as possible.

Also remember that next year, the components may change somewhat and a different brand, series or lot number will work better.

 

[GAF]

That is exactly why I and others use the same box of ammo that we sight in our guns for deer hunting for the actual hunt.

 

[Slamfire]

The further you go out, the more of a difference you will see in point of impact.





Even with a three quarters MOA adjustment up, the group was down. It was not very accurate either.



I bought the stuff at $4.71 a box, it was about time I blew the contents down range.

 

[rodregier]

As far as groups go, there is a lot of variability in the quality of bullets loaded in both factory ammunition
and available for handloading.

As a general theme, FMJ projectiles will tend to group more poorly than SP or HP in same weight.
This is in large part due to the bigger technical challenges in making consistent bases for FMJ projectiles.

I have read that the quality of the base is a large factor in accuracy, the nose is a big factor in trajectory.

As an example on accuracy part, Hornady's "Hornady Action Pistol" (HAP) projectiles as both a reloading component and loaded in factory ammunition (by both Hornady and Wilson Combat) are among the most accurate pistol projectiles on the market today. They are a flat base hollowpoint design without the skives to promote expansion - being designed for punching paper or ringing steel.

Wilson Combat quotes this accuracy claim:

https://shopwilsoncombat.com/9mm-Bi...-FPS-5-Barrel-100_Box/productinfo/A9-125-HAP/

"The Signature Jacketed Match 9mm load has been extensively tested in 1911 style and other high-performance firearms and is the most accurate 125 grain 9mm ammunition available. We guarantee the Bill Wilson Signature Jacketed Match to shoot 25 yard, ten-shot groups through a fixed barrel testing device of under ONE-HALF (1/2) INCH-GUARANTEED."

I like using the 125g HAP in my 9mmx19 reloads.

https://www.hornady.com/bullets/hap#!/

 

[Zaydok Allen]

Yup

 

[FL-NC]

Truer words were never spoken. It took a friend who is a hobby reloader to develop a round for me that exploits the full potential of my Ruger American 308.

 

[FROGO207]

Even though I reload (for center fire) I still buy an assortment of rimfire and try it in my various rimfire firearms to find what shoots best in each one. Have been doing this for years with great results so comes as no surprise it would hold true to factory centerfire as well.

 

[rodregier]

Since reloading for rimfire is not practical in any volume, the only real alternative is to buy various brands or even manufacturer production lots of rimfire ammunition to find what works well in a specific rimfire firearm.

I've read that in the very top level of .22LR rifle competition, competitors have to select numbered production lots that work well in a specific barrel and buy several cases of the same to use in competition. Some of the top-end rimfire ammunition manufacturers have testing centres in the US and Europe to specifically support this competitor activity. The competitors consider such barrels "worn out" after say 25K rounds (no longer delivering top-level competitive accuracy). Replace barrel, rinse and repeat.

Read a story about an accuracy gunsmith decades ago that would replace a barrel, find a lot that shot well in testing in his shop and sell 5 cases of that lot as a service.
(He used the corner to corner diagonal of his shop afterhours for testing

 

[lionking]

factory lot was mentioned also and is true that even the lot number can vary accuracy or more often impact area. I have several lots of Greek HXP from the CMP, I can zero in my Garand or other 30-06 with a certain lot but then impact area of groupings will change with a different lot even if the lot was made the same year. So I learned the rifle you have sighted in might not be next time if you just change a different lot from the same year. A shift of impact area that was center bulls to 2 o clock of bulls or where ever of the bulls makes a big difference.

 

[Archie]

So I learned the rifle you have sighted in might not be next time if you just change a different lot from the same year. A shift of impact area that was center bulls to 2 o clock of bulls or where ever of the bulls makes a big difference.

Which is why I preach to any who will listen to the screwy old man, ANYTIME one changes one's rifle or ammunition in any significant way, re-verify the zero! No point in having a quarter minute of angle group some eight or ten minutes of angle from the aiming point.

 

[Blackstone]

As a personal anecdote, I saw a huge difference between Magtech factory .38 and homeloaded .38
At 25 yards, from a benched marlin underlever, the factory .38 had about a 4 inch group, whereas the homeloaded .38 gave about a 1.5 inch group.

 

[Erief0g]

I've really enjoyed loading up different recipes to confirm best shooting loads. Few trips to the range ago I brought some win white box I've had in the safe. WHAT A DIFFERENCE. That right there reinforced why I reload something as economical as nine mm.

I had been shooting my own recipe for over 2000 rounds and I was very surprised how poorly my old practice ammo shoots. How many 1000's of rounds trying to shoot better and better not realizing that a percentage of errors may not have been "all" bone

 

[rodregier]

Alas, handloaded ammunition isn't a guarantee of better accuracy than factory. In general the quality and suitability of the projectiles is the biggest variable.

 

[rodregier]

Just speculating - in the case of milsurp ammunition, there is probably enough variability in storage conditions that
case lot to case lot variance with same mfgr lot number effectively makes each case lot it's own production lot :-(