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300 yard group size

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03 June 2009, 17:03
Rambo
300 yard group size
I was wondering about what would be considered a good and an excellent five shot group size at 300 yards. I can do in the .2's at 100 but not better than 1.5 at 300 on a reasonably calm day. Targets are the same but 3x bigger. I would think it can be three times the size at three times the distance but it's not. I have tried this with various loads as well. Does a very slight breeze open them up this much? What kind of groups are you guys doing at 300?
03 June 2009, 20:18
Cheechako
Rambo

Though there is no formula, group sizes are not porportional to the distance. There are too many environmental factors that come into play, the most important of which is wind. Unless you are using wind flags and have the ability to read them, you're wasting your time trying to shoot better groups at any distance.

"Good" and "excellant" groups at 300 yards are a function of the equipment. Benchrest groups of well below 1/4" have been recorded while a group with grand-dads 30-30 would be considered good if it could be covered with a dinner plate.

Ray


Arizona Mountains
03 June 2009, 22:02
rcamuglia
Rambo,

I think that 1.5" at 300 is great. It's 1/2 MOA and, depending on your rifle's quality, will work!

What kind of rifle do you have?
04 June 2009, 03:25
Rambo
I have several rifles that can shoot under half minute, the one I am referring to is a 30-284
04 June 2009, 06:04
rcamuglia
I wish I had one that will shoot that well!

I'm posting on the reloading forum on a subject quite like this. I'm trying to develop a load for my .300WM that will be good at long range. If you would, check it out and give me some suggestions if you have any.

If my gun shoots 1.5" tomorrow at 300, I'll be tickled! This one shoots well at 100 then goes south at longer ranges. I haven't tried the new load that is pictured at long range yet and I am keeping my fingers crossed. I wish it would hold .5 MOA out to 1000 yards! If yours do, good on you!!!!
04 June 2009, 06:45
Wm.S.Ladd
6mm 284 and 6.5mm 284 are current favorite calibers in competition benchrest.

Wind at 300 yds opens up groups. Also, you're losing velocity and that opens groups. 1.5" at 300 yds is .5 MOA. That's pretty tight.

You go out 600 yds, and the group really starts to open because you're running into drag, wind, and loss of velocity. Those all affect groups.

VLD bullets (Very Low Drag) help at longer ranges. Benchrest caliber velocities out beyond 600 yds. tend to be "bore burners" -- 5000 rds. and the bore is shot out.

I like a Rem. 700 Police in .308 Win. out to about 600 yds. 168gr to 175gr bullets, 1:12 rifling. You need to match bullets w/ rifling. There's some links online for this -- Barnes or Berger, I forget which.

Seems to work for the US Marines. (M-40 sniper rifle) The Rem. 700 Police is the same basic rifle, no adj. pull. And you can put better glass on it than the Marines. (Leupold Mark 4, w/ bases/rings, 6.5 - 22x 50mm w/ Alumina objective hood.)
06 June 2009, 00:02
rcamuglia
Update if you haven't seen it on the Reloading Forum. I got my gun to finally shoot!



This is a 1.177" group shot at 300 yards. I happier than a pig in poop!







10 June 2009, 04:27
butchlambert
Rambo, Cheechako is one of the better long range competition shooters. He knows what he is talking about. You may have a half minute rifle, but without windflags you will not shoot consistent MOA groups at 300yds with as little as a 10 MPH wind.
Butch
28 June 2009, 19:22
sonofagun
And just how did you measure that group size to .001" accuracy?

Confused


Bob Shaffer
30 June 2009, 10:39
N E 450 No2
I have found that Blaser R 93 sporter bbvls will shoot under 4" at 300 yards on a regular basis.

With some ammo they shoot better.

The 308 match bbls will shoot under 1.5" at 300 yards with Federal match.


DOUBLE RIFLE SHOOTERS SOCIETY
02 July 2009, 20:15
Peter
I recently shot the target below at 100 yards with my Blaser R93 300WM barrel using 168 grain SMK's. I plan on trying it at 300 (and further) when it cools down!


There are 5 rounds in the cluster. The hole above the group is because I had to use a "used" target. That's what happens when you go to the range without targets!
Peter.


Be without fear in the face of your enemies. Be brave and upright, that God may love thee. Speak the truth always, even if it leads to your death. Safeguard the helpless and do no wrong;
03 July 2009, 01:36
rcamuglia
quote:
Originally posted by sonofagun:
And just how did you measure that group size to .001" accuracy?

Confused


I did the best I could measuring the outside spread of the most distant holes with a caliper, then I subtracted .308" to get the center to center measurement of 1.177"!
20 July 2009, 00:33
homebrewer
quote:
And just how did you measure that group size to .001" accuracy?

I use a circle gauge and find the one that best captures the group, and subtract the diameter of the bullet used. Small circle is 19/32 (.285 group); big one is 1.125 (.817 group) to capture every shot. No shinin' on of anything, here. We're talkin' full disclosure.....

20 July 2009, 15:11
DocEd
"...full disclosure". The problem is, according to you posted pics, is that both circle guages appear to be too small. The line, on the target, appears to be disecting the outside circumference of the bullet hole. This will result in a smaller measurement. Measure the group, at the widest point, with a dial caliper and then subtract the bullet diameter.


NRA Patron Life Member Benefactor Level
21 July 2009, 00:59
homebrewer
quote:
The problem is, according to you posted pics, is that both circle guages appear to be too small.

They are as close as I could get with the template I had, making sure I didn't go too small. I made sure I didn't cheat. The thickness of the pen is why the circles look too small. Before I drew the line, the circle template got all of the hole but nothing less than the hole. I wanted to be true to myself, above all else. Who said that? Some guy in a funny-looking collar from England in the 17th Century, I think it was...
21 July 2009, 15:46
DocEd
Whatever blows your skirt up.


NRA Patron Life Member Benefactor Level
22 July 2009, 07:59
groundhog devastation
I've seen some great 100 yard rifles that weren't worthy of trusting at 300 yards. By the same token, I've also seen some rifles that were fair to mediocre at 100 yards(.5"-.7") that were pretty darn close to that at 200 and 300 yards(One 6mmVLS comes to mind!!!). Every barrel is different, every rifle is different. Bottom line from my standpoint is, if you have a 1/2MOA(1.5"@300) rifle, you've got a pretty darn good one with a pretty darn good load! I used to have a signature line that read:
"1/2 inch @ 100 yards is easy! 2 inches at 500 yards is somewhat more difficult!. I still adhere to this saying, Charlie (GHD)


Groundhog Devastation(GHD)
24 July 2009, 00:36
rcamuglia
An update on the rifle I shot that 1.1" 5-shot group with.

It has never duplicated it.

Any ideas? Luck? Re-work the load a touch? The load is good and stays withing a MOA but hasn't come close to that amazing group!
24 July 2009, 08:57
jb
next time watch the wind closely.even small changes in wind will drift bullets.I noted this with a 17hmr at 100 yd ranges.
Also variation in velocity will cause dispersal(vertical spread) with longer ranges.


******************************************************************
SI VIS PACEM PARA BELLUM
***********



26 July 2009, 22:07
sonofagun
You miss my point - saying you can measure info from ragged holes in paper to .001" accuracy is a stretch. Even to .01" ain't easy.


Bob Shaffer
30 July 2009, 01:57
rcamuglia
All you have to do is dial your caliper to touch the outside of the furthest bullet holes then read what is says.........

Subtract the diameter of the caliber you are measuring........

and viola! you have the measurement of your group, center to center.

It beats using a Stanley tape measure for accuracy.
30 July 2009, 04:58
scr83jp
We had a GS who was really great at bedding and tuning rifles and handguns,he did most of the handguns for le in the area.He bedded a sako 300wm for a friend who took it top a local range at 100 yards put first 3 shots into a .308 hole.He never advertised but requests would come in from around the world for his rifles or for repairs.He passed in 1990.
30 July 2009, 05:15
butchlambert
I've done several of those that every once in a while did that, but didn't let anybody see the others.
Butch
02 August 2009, 20:12
sonofagun
quote:
Originally posted by rcamuglia:
All you have to do is dial your caliper to touch the outside of the furthest bullet holes then read what is says.........

Subtract the diameter of the caliber you are measuring........

and viola! you have the measurement of your group, center to center.

It beats using a Stanley tape measure for accuracy.


No kidding? Like I didn't know that!

Try repeated measuring of the group by several different persons and then see how repeatable a measurement to .001" is. Such accuracy requires a definitive subject to measure such as a piece of steel - smudge marks on paper are not very definitive.


Bob Shaffer
05 August 2009, 21:31
rcamuglia
Are you so anal that it matters to you if the size of your group is off by .010" either way?

Or even .1" ?

I'm not.

Using a caliper is the most accurate way I can do it within the bounds of accuracy problems you describe. Do you have a more accurate method to share with us?
06 August 2009, 00:41
Peter
RC you are not going to win this one. You committed a cardinal sin by posting on this board without genuflecting to the experts first!
Explanations like "subtracting a 3 decimal place number from a one decimal place number will ALWAYS result in an answer that is three decimal places" are lost on these gurus.
Peter.


Be without fear in the face of your enemies. Be brave and upright, that God may love thee. Speak the truth always, even if it leads to your death. Safeguard the helpless and do no wrong;
06 August 2009, 01:09
rcamuglia
I figured.

Thanks!
06 August 2009, 07:53
butchlambert
rc,
Not to worry a scale would be close enough for 90% of groups.
06 August 2009, 20:07
rcamuglia
Update from this morning at the range:

Bought some Nosler brass for my .300. Loaded the same load that shot the 1.177" group at 300. Shot a 2" 5-shot group after 5 down a clean cold barrel at 300.

Went to a 100 yard target and it was terrible.

Dialed the 300 yard paper again and group was good.

Dialed a 425 yard 6" round hanging steel gong, played the wind and held on the right side of the plate, and put 2 within an inch of each other on the plate.

The brass was brand new with no fire-forming. The rifle shot OK, but I hope it gets better when all the brass is formed on the second loading.