3rd or 5rd groups and how many?

[clrems77]

Trying to develop new loads and have been using 3rd groups. Been reading about people using 5rd groups. So my question is which is better/more accurate for load development and how many groups do you shoot per load?

Thanks in advance!

CJ

 

[Whiplash5198]

I've been using 3rd groups for 25yrs and it seems to work for me. Some will say 5 rds. I feel 3rds gives me a good indication of what's going on. Also, when the reloading budget is an issue, or component availability, it helps to conserve supplies.

 

[steve123]

I've been using 3 or 4 round groups the last couple years after having done a ladder test. Mostly testing for seating depth at this point. If I have two that hit far apart then I disqualify that depth.

If you are having 3 rounds touching most of the time, meaning that you've confirmed this load, you are pretty much done with load development.

Most of my cartridges are overbore so I want to save the barrel as much as possible. Plus load development is tedious and time consuming.

 

[DieselWSM]

I've been using 3rd groups for 25yrs and it seems to work for me. Some will say 5 rds. I feel 3rds gives me a good indication of what's going on. Also, when the reloading budget is an issue, or component availability, it helps to conserve supplies.

+1

I had an intense discussion on this very matter with a fellow shooter a few weeks ago. IMO...if I can stack 3rds in the same hole I feel that for me, it is a successful load and no need to shoot 5 rds. I have been doing this for tactial match loads for a few years and been very successful. On the other hand, if I am working on a load for F-Class, it is a 3rd group to find the best node, then I start shooting 5rd groups and refining my load a little more.

 

[ptaylortx]

I use the Newberry OCW test, then I adjust my seating depth with 4 shot groups.

 

[witchhunter]

I use 3 each 3 shot groups and average them. 9 shots of the same of each group. has been working for years.

 

[base]

I do two 5 shot groups per specific powder charge.

 

[leadbullet]

I like several 10 rounds groups per charge variation, I feel I get more consistency out of the load and rifle combo and never tests under 300 yds.

 

[bruddah]

My thought has been 3 shots tests the load. 5 or more tests the shooter.

 

[MitchAlsup]

3 shot groups lie to you more often than they tell you the truth.
5 shot groups tell you the truth more often than they lie to you.
4 shot groups are about 50%/50%.

 

[Hondo64d]

3 shot groups will tell you if a load is bad, but will not tell you if a load is good. There have been far too many times where I might get a 3 shot group in the .4s or .5s only to not be able to repeat it. Or I might get two touching and another an inch or more out. Sometimes I might get a couple of consecutive 3 shot groups that were really good but wondered why the POI was slightly different between them.

Finally I started stacking the 3 shot groups and the light came on. Those "fliers" aren't… They are part of the group. If your goal is to use your group as a predictor of where future rounds are going to hit, 3 shot groups generally don't cut it. They CAN if you use them the right way. Shoot multiple 3 shot groups at the same point of aim and see what the composite group irons out. But, for me, a single or even couple of three shot groups shot at different points of aim have generally only left me scratching my head as to why my results aren't repeatable.

John

 

[JoshcBoucher]

What I've been doing, lately, 3 shots for general, then 5 shots to dial em in.

 

[diderr]

3 works best IMHO. You'll get a very good idea how a load shoots off 3. It's enough to see the harmonic nodes rise and fall. 5 shot groups you are just taking away 2 bullets you could use for another test. You can use 5 to "confirm" a good load.

 

[samnev]

My thought has been 3 shots tests the load. 5 or more tests the shooter.

I totally agree with this. I have shot many sub 0.25 moa 3 shoot groups only to get "Buck Fever" on the 4th or 5th shot to open the groups way up. I know it's my fault as I can usually call where the errant shot will land.

 

[lte82]

When I did some iron sight work recently with my service rifle I did 5 shot groups for the load work up, then took the top 2 and did 10 shot groups to find the best one. For big bore cartridges like the 338 LM or 300WM, I'd settle for 3 shot groups for the initial load work up, then take the best 2-3 loads and go for 5 shot groups to come to a final conclusion.