5-Shot Groups & Flyers

[brut28481]

I am working groups up with 130 Berger/123 Amax/CFE with longer COAL (see previous Lilja thread) shooting 5 shot groups. Some of my groups will have three shots bug holed together with one or two flyers. Are these groups worth pursing?

My thought is if the load is capable of grouping three out of 5, the other two must be operator error/powder/brass/etc....?

Thoughts?

[lrgrendel]

Shoot 10 shot groups.
This will give you the most accurate information.

[JASmith]

A lot depends on how far out those flyers are and what you plan to do with your shooting.

For example, if you are hunting medium game, you should be able to keep all of your shots within a 10-inch diameter circle at 300 yards. So, a consistent 1.5" wide group at 100 yards will allow you to do that with about a two-to-one margin.

If, on the other hand, your goal is to take out flies at 100 yards with that bug hole group, you might need to do some ammunition adjustment and shooting technoque improvements...

[mongoosesnipe]

there are a lot of factors that go into a group if three shots are touching those are probably 1/4 moa if the other 2 are less than an inch away your still high around a minute which is a very acceptable group for a semi auto gun the psg1 and m110 ar both 1 moa guns they often shoot better but that is the standard for reference the psg1 accuracy standard its a 50 shot group in an 80mm circle at 300m (1moa)

are your first 3 clover leafing then 2 fliers, are all of the round mag fed under the guns own operation often the first round manually chambered from a magazine will shoot a little different from the ones the gun feeds its self, are you stringing vertically or horizontally, did you lube your gun with unicorn spit, what was the phase of the moon....

but in all seriousness what was the measured group size and what are you chasing most of my guns shoot better than me and if i do my part i can throw together a nice group but there will be times where one group is trash then i shoot a nice one and the next one will be blah again while pretty much all of them would certainly be combat effective...

[Klem]

Should you keep the good groups and discount the bad ones?

Depends if you are testing the gun in isolation or the whole system.

Drummed into us when I first joined the military were the four factors of producing an effect down-range; gun, ammunition, weather and shooter. I would add to that a fifth; the shooting platform (whether it is bench rested or bi-podded, or shot from kneeling, sitting, prone etc).

If you are wanting to know the accuracy-potential of the gun then you will want to eliminate all other variables that might make the group larger than the guns potential. Get a good shooter. Shoot on a calm day, using the best ammunition and from the most stable rest possible. If the shooter calls a flyer as their fault then discount that group. If a sudden gust of wind upsets the group then discount it. If the ammunition is known to produce flyers then discount all the flyer groups. The opinion going round the F Class club I belonged to was that 155 Winchester Palma match factory ammo (.308) shoots one flyer in 10 rounds. In this case discount any group that has a flyer.

If however you are wanting to know how accurate the whole system is, because you want to shoot competition or hit game in a likely scenario then you need to consider the average result of the whole system. You need to 'own' every group and discount nothing. By own I mean you need to include all the bad shots as well as the good ones. Heck, some days I shoot well and some days I am woeful. It is tempting to consider only the good results, but if you discount anything bad during load development then you are deferring disappointment until it actually matters.

[brut28481]

Great responses. The goal is to create an effective load for 1,000yd consistent hits. I have started competing in some PRS matches with the Grendel so a dependable load is ideal. I have honed in a dependable load with XBR and thought I would revisit CFE with loading closer to lands. I am exploring the 130 Berger with CFE since it looks to be a slightly better long range projectile then the 123 Amax if you can get the velocity and accuracy. I am feeding all the long COAL with an AA notched mag. Agree on owning the groups. I have experienced the same thing. Running 5 rounds sets of the same load. First couple are worth a crap. Then when the stars align and the wind blows from the SE at 2.5 mph on the first Friday of the month, sub MOA group! Referenced groupings below:

[mongoosesnipe]

i haven't done much past 300 just don't have the space, if your goal is to be competitive at 1000 you really need to stretch your shooting out past 100 vld bullets act differently as the range grows, and they are not the most consistent bullets at close range look at the bullets bench rest shooters use under 300 flat base bullets dominate past 300 you start to benefit from a vld design

[brut28481]

Has anyone tried this process recomended by Berger for VLD bullets for the Grendel, if so did it work? :
Load 24 rounds at the following COAL if you are a hunter (pulling a bullet out of the case with your rifling while in the field can be a hunt ending event which must be avoided) or a competition shooter who worries about pulling a bullet during a match:
.010 off the lands (jump) 6 rounds
.050 off the lands (jump) 6 rounds
.090 off the lands (jump) 6 rounds
.130 off the lands (jump) 6 rounds
Shoot 2 (separate) 3 shot groups in fair conditions to see how they group. The remarkable reality of this test is that one of these 4 COALs will outperform the other three by a considerable margin. Once you know which one of these 4 COAL shoots best then you can tweak the COAL +/- .002 or .005. Taking the time to set this test up will pay off when you find that your rifle is capable of shooting the VLD bullets very well (even at 100 yards).

[FW Conch]

I have done this with a bolt rifle, and it works great. I have a 30/06 that shoots it's best load .160" OTL's. Great barrel for long, heavy pills.

Jamming the lands, chasing the lands, is a way overrate fad, IMO. :-)

[mongoosesnipe]

this was playing around with the last AR i threw together all the loads were the same 223 with 75gr hornady hpbt over ar-comp loaded mag length in random brass my rest wasn't great so my shooting was not consistent, point being you actually need a large sample in order to call a load good or bad as for chasing a 1000 yard load with the grendel just don't push it to far the gains of picking up an extra 30 fps are probably not worth the required press increase and probable less consistent which in more important to good shooting than extra velocity as long as the load isn't going trans sonic your velocity is good enough