Why do we shoot 5 shot groups. i can hold it together for 3 or 4. then i get so nervous i always shank the 4th and/or 5th. I was breaking my best group ever, then flew the last 2 out of the group. .077" for crying out loud...WHY!!!!

p.s. you get to see my hand becuase i cover my load data! CYA

Wow that is some nice shooting. Congrats.

alot of people shoot 5 so they can measure the best 3, 3 shot groups are good for sighting in, 5 shot @100 when trying to find the sweet spot and 10 shot strings at 200 when you are really getting nit picky on finding the perfect load

Three shots test the load, four shots tests the rifle, five shots test the loose nut at the wheel.

loose nut....guilty

Pretty much what I was always taught

Yup

BTW....nice shooting, but as a reloader if I can't repeat the load and results than it don't count! Have you been able to duplicate it or is that your first test?

i am taking offense that yall keep chiming in call me a loose nut... haha truth hurts i reckon. but just for once i want a 5 shot group. its never the first 3 that fly. always the last one or two ehn i realize what i got going.

Because 5 shots is a group. Three shots is just something go show your buddies.

^^^^^^^^^^^THIS^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

always kind of preferred the one shot group myself. from a cold barrel shoot one shot a day for 5 days at the same target.
Three shot groups may be for your buddies, five may be for your gun, but one shot groups are for the game.

But if it will stack the next four right in there with the first shot, you have now seen what the rifle, shooter, and ammunition are capable of.

I don't think anyone is denying the fact that, in the field, the first shot is the one that matters.

One shot a day will do the exact same thing, just takes longer.

Kyle

If we could answer why this happens perhaps we could fix Tony Romo's problem. I had one rifle Remington 700 that would put 2 in the same nole or at least touching, then start trowing them a little out. After a glass bedding the action and free floating the barrel it would then stack them. Before that I could get it to stack the shots by shoot 2 wait at least 30 minutes let the barrel cool then shoot 2 more and wait again. So IMO it is not always the loose nut, sometimes it is the equiptment. If it happens with only one gun start trying to find out why. If with multiple guns start concentrating more on consistant form and follow through.

In my case It's always the third or fourth that ruins the group

IMO if you are a hunter several 3shot groups from a cold barrel will tell you more than 5shot groups. As in hunting younrarely shoot more

Of course if comparing loads for accuracy you can test for it in anyway you feel more comfortable. If you own a chrony std deviation will also contribute to understanding which is a better load. Wind is also a big factor often overlooked at 100 yds but when you are measuring half an inch stuff every breeze counts. it also depends on your caliber if it's a .223 at least shoot five if its a .375 or a big mag three shots is brave enough. My 2cts

Kyle,

Do you measure/correct for run-out?

David

it was at 100 yards with a 6mmBR, i do own a chrono and i get a spread of about 15fps using varget. I do not measure run out. do you think that it what it is david? it does seem flyers ten to be up and to the left (10 o'clock'ish).

[quote=30378]

^^THIS^^ and

Kyle,

Are you right handed? Could be pulling the rifle, causing the 10 o'clock shift. That and a heated barrel, I'm just spit ballin' here though.

What poundage is your trigger pull?

Honestly I don't know! I am just beginning to explore run-out issues and am far from an expert. I asked the question because this is the sort of phenomenon that is reported to be attributable to run-out.

I have read quite a bit of Barsness (and others) and their opinions seem to stand some long held handloaders beliefs on their heads. I have read that old factory ammunition typically has measured run-out as much as .010 - .011" (I don't have any old factory ammunition to measure). This old factory ammunition is often incapable of measured accuracy less than about 2" at 100yds. Modern factory ammunition is much better, typically run-out less than .007" hence the improvement in accuracy in modern firearms.

Typical hand loads are supposed to have run-out more in the order of .002 - .005", hence the large increase in observed accuracy. This decrease in run-out of handloads contributes (much) more to the over-all accuracy than the case being fire formed to the chamber. To get the tiny groups that we crave run-out must be reduced to less than .003", preferably less than .002".

I received my Hornady Lock-n-load cocentricity tool this past Thursday and began measuring ammunition. A favorite factory load for my 338Fed is the 180grn Accubond. It typically will shoot 3 shot groups around 1". Often 2 shots are touching with a 3rd opening the group to about an inch. I measured two boxes of this factory stuff - Most of it had about .004" run-out, but 1/3 of the rounds measured .006-.007". Hmmmmm....

I measured a warm handload (160 TTSX at 3030fps) for the same rifle that normally gives 3 shot groups 0.5"-0.75", but 5 shot groups always open up to about 1" or just under. Measured run-out was around .003" for most loaded rounds, but about 1 in 5 (4 in a box of 20) had measured run out of .005-.006". Hmmmmmm.............

Then I got to thinking. I have a Benelli R1 that delivers nearly unbelievable accuracy w/ factory 150grn Hornady SST ammunition:



I know, an autoloader can't shoot like that, but this one does. I never got around to buying a set of dies to load my own ammunition for it because as soon as I saw how it shot w/ this relatively cheap factory ammunition, I bought 20 boxes of it and let it be. So I pulled two boxes of the factory Hornady SST ammunition and measured them. out of 40 rounds, only 3 were over .003" and then not by much (.004"). Hmmmm...... (No, I do not think all Hornady ammunition is this good, I think I lucked into buying a good batch - maybe they just got through adjusting all of their machines...)

One of the neat things about the Hornady tool is that it not only measures cocentricity, it allows you to correct it. I corrected my 160 TTSX loads, some 200grain SST loads and 1 box of the factory accubonds all to less than .003". Unfortunately, I have not had the time to shoot the corrected rounds to see what (if any) observed differences there are. It's all just theory for me at the moment, but there do seem to be some observed phenomenon lining up with the theory. I'll know more when I have a chance to shoot some....

I would be very interested to hear of anyone else's experiences as well.

Regards,

David