AVG Group Size

[Jon Tucker]

Question for you? How many groups do you shoot to verify a final load? I have a worked a great load, showing consistent velocity and low SD. When I shoot 5 shot groups, I get any where between 3/4" to 1/2" groups. If I went by the first group ever I shot with this load, I would of lost the load due to 1.10".

How many groups do you shoot to test the load?

Do you judge the final load by an average of multiple groups shot?

 

[Rick Richard]

I wish there was a final group, but I continually tweak and am never satisfied with the last group shot, ha!

 

[dok7mm]

I shoot numerous 5 shot groups in different conditions. I'm always tweaking seating depth, primers or powder. I will always have a favorite load to fall back on, but it's never perfect.

 

[Greyfox]

I got into the habit of testing a final load a minimum of three times on separate days at 200 yards from a prone or bench position with Bipod. I will shoot 1 cold bore and 2 follow ups for a measured three shot group. The average of all groups is what I consider my rifles accuracy level. For my LRH rifles I'm looking for .5MOA/ES 15FPS or less with both. If not, it's back to the drawing boards.
A recent 6.5x284 build. 200 yards on three separate days.

 

[YZ-80]

Early on, I'll shoot 5-shot groups, then taper down to 3 because I want to save some rounds for the field without having to hit the reloading bench in the middle of the season. I'd say that I'm looking for repeatable accuracy out to 300 yards on at least 2 independent range sessions for each temperature range (summer/ fall). I test in summer because I have more time, but we all know what happens to POI at lower temps. So if I'm .5 MOA and less than .5 MOA vertical dispersion @ 300 I'm done.

 

[BrentM]

If my load has a low es and sd and yet a crappy group I'll reshoot as it's probably the trigger jerker creating the problem. I do tend to test my rifles at 500 tho. If it shoots well at 500 I go 700-800 and then 1000. If all seems good to go, I'm done. I've had some really bad ES/SD loads shoot bug holes at 100 so I don't care about close range groups, that only matters for zeroing.

 

[rsbhunter]

I would think It depends on the purpose of the rifle and what you consider good enough. For benches, until it's in the .0? It may not be competitive. For 100yd deer, 1"-1-1/2" is plenty...BUT your acceptable limits is what counts....I believe that two groups of three rounds on different days, that keep the group where you like is ok. I'm using hunting guns, so my needs are my own. Working up loads is a hobby in its self, and a lot of fun....I believe it depends on you.....have fun, shoot as much as you want...rsbhunter

 

[jrock]

I stop shooting when they all go into one hole. Ok, just kidding, sort of. I have expectations for each gun. If its a factory rifle, I don't stop until I'm at least 1/2". If I can't get there, I usually sell it. That is why I tend to build them as my expectations for those are much higher and I've never had sell one of those because it didn't shoot as well as I wanted.
After I pick the best load from my load development, I usually shoot groups to confirm the load development is stable, temperature sensitivity, and some for zeroing. Probably about 8 to 10 groups.

 

[tuscan]

I got into the habit of testing a final load a minimum of three times on separate days at 200 yards from a prone or bench position with Bipod. I will shoot 1 cold bore and 2 follow ups for a measured three shot group. The average of all groups is what I consider my rifles accuracy level. For my LRH rifles I'm looking for .5MOA or less. If not, it's back to the drawing boards.
A recent 6.5x284 build. 200 yards on three separate days.
View attachment 145863 View attachment 145864 View attachment 145865

Looks like you need to zero that POI .1mil to the right!

 

[Greyfox]

Looks like you need to zero that POI .1mil to the right!

LOL. The correction flipped me on each side of the dot. Figured I'd err on the side of spin drift correction....

 

[BrentM]

LOL. The correction flipped me on each side of the dot. Figured I'd err on the side of spin drift correction....

I like .25-.5 moa left so I don't have to mess with spin to 1k. Just use my correction in my head, hold, and send it.

 

[rsbhunter]

Tuscan, it's funny that you posted that target. Here's a target from the only custom bolt gun I ever had built...I honestly was concerned with the group being off to the right...until I learned about the spin drift and coriolis effect....I have shot multiple groups at 500 that are 1/2"...300 RUM , Krieger hvy bbl, Jewell trigger..Zeiss scope...with a bbl life of around 1000 rnds, it is my long range hunting rifle...

 

[crkckr]

If I can get 3, 5 shot groups down to .5" I usually call it good. Then I will retest in differing wx conditions to make sure the rifle (and I) can maintain the group size. If something goes haywire along the way., it's back to testing again.
Cheers,
crkckr

 

[jasonco]

Multiple "final load" groups shot several times, various conditions, different days and different ranges. With a cold bore shot and 3 or 5 shot groups. This ain't F-Class, just long range hunting, shots 1-2-3, is what you want to see, going the same POA. This is where I'm at right now, finally. Plus I'm waiting for this dang hot bleepin' weather to go away, to see how the loads hold up in the most likely conditions I'l be hunting in?!