What 100yd group size can you expect with a 6.5x.284 or 6 Dasher

T

tcombest

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I frequently shoot 100-200 VFS with a 6ppc or a 30br and some 400-1000yd stuff with a 6.5x.284 and 6mmbr dasher.

When load developing the short range guns, if conditions are really good, I can shoot consistent groups under .2 and often much better. Many times in the 0.1's and below.

6ppc - 68gr Cheek, Krieger, BAT
30br - 1:17 118gr Cheek, Krieger, BAT

However, when load developing the long distance guns (6dasher and 6.5x.284), I can never get consistently small groups like the short distance guns. I probably get 0.2-0.4" groups. I often can get two bullets through the same hole and then one slightly off. These two guns are 1:8 twist and shooting 108 Bergers and 140 JLK's.

6 Dasher - BAT M, 108 or 105VLD Bergers, RL15 or 4895, 1:8 twist, 2950fps
6.5x.284 - BAT M, 136 Hoover or 140JLK, 4831SC, 1:8 twist, 2950fps

Here is my question: When you shoot the 1:8 twist guns that are set up for long distance, can you really expect to be able to tune them to shoot consistently tiny groups like the 6ppc or 30br? Or should you be satisfied with a 0.2-0.4" group?

I have talked to other 6 dasher shooters who say they don't even mess with shooting at 100yds because they all go through the same hole.... so they load test at 400 and out. Im having a hard time believing it.

I know Lynn / Waterboy shoots a lot of 6mm stuff long distance. I value your opinion, so I would love to hear your thoughts. And anyone elses please.
 
I do all my load work at 1k, with my dasher. Shooting at 100 can lie to you.

What looks good at 100, may look terrible at 1000. :D

Easier to see vertical when shooting at 500 plus yards, that will let you know what's going on. :cool:
 
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OK, you wanted opinions...... here's one worth exactly what you've paid for it.

It is my OPINION that if your gun's not shooting .2's at 100yds you stand little chance in today's 600yd-1000yd games. Yeahh, if you're a good shooter and it's wicked switchy

and you're lucky

you'll beat plenty of people whose guns suck worse. But you'll rarely beat the consistent few whose guns DON'T suck! And if the weather bureau blesses you with a trigger pull it's kinda hard to shoot 2" at 600 or 4" at 1000 with a gun that shoots .4 at 100! Contrary to popular belief groups DO NOT tighten up with distance. Some just fall apart less.

No it will never shoot in the ones like you need at 100-200, in fact it'll shoot twice't-too-big, but it still needs to be bugholing.

I completely agree that vertical is easier to see at 500, PROVIDED you've got a flat, fairly consistent range....... otherwise it's kinda' hard to separate the vert from the gremlins. That said, vertical just isn't as much an issue if your ES is down around 10fps. Still nice to be in the middle of a node but less important than when you're splattering lead across 50fps spread, jacking the hand crank on a powder pump.


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al
 
Ok, Al

I have to admit, I agree with everything you've told me. I hope more people will chime in on this topic because I would like to hear what others have to say. I've always felt that if I could consistently shoot a .25 MAX at 100 in good conditions, that the gun would compete. I don't want to burn out a barrel trying to shoot a sub 0.1. Again, my gun is consistently putting two bullets through one hole, then one touching at 100, so I don't think I can tune it any better than it is. It's probably shooting a sub .25, maybe a sub 0.20

I think that load developing at 200 yards might be a better idea. It's hard for me to find a 400+ range to shoot on.

We do a lot of redneck clay bird 400 yard shoots out here in West Texas. We shoot the 6", 4", and 2" birds.

Probably the best 400 yd shooter out here told me he wants to be able to shoot a 1.2" group consistently at 400 so he can have the best chance to break the 2" clays. Makes sense to me.

Our shooting down here is much different than the shooting on the ranges cut through the pines up north. We have serious switching winds down here, ususally 10-25mph and heavy mirage.

Thanks for your opinion and post.
 
I do my load development on a 200yd benchrest range, I found that for initial tuning if I get it shooting .3” at 100 with an acceptable velocity spread, I don’t waste the barrel and go straight to 200, if the load is in tune the group wont open up.

Then I’ll try a different pill or powder combination to achieve the same result, I make my final load selection when it’s been shot at 600.

Works for me
 
I think it's nearly impossible to get long heavy boatail bullets from long barrels, shooting anywhere near short light flatbase bullets from short barrels.
Nor will it ever be needed to compete at 1Kyd.

Different games
 
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Tcombest
Sorry for the delay I have been on those other threads and haven't read this one.

I don't shoot any 6.5's and I never will so on that one no comment

On the 6Dasher your bullets determine the group size.Typicaly with the Sierra 107's you will get about 0.230 groups on a well tuned load.
On the Bergers its all about consistent seating depth so if your bullets are not sorted to match your particular comparator your going to get exactly what you just described.
If your gun likes 2.500 for its seating depth at 100 yards using the 105's you only have a 0.002 0.003 tolerance before the groups open up.That means 2.499 2.500 and 2.501 will shoot very well but 2.502 and 2.498 will give you a bullet that barely touches the others or your 2 and 1 group.
Those numbers above are for an example only as I don't remember my actual values off the top of my head.
To test this out for yourself load up 30 rounds and seat each bullet individually while using your comparator.When you find your best load lets say its 2.500 inches load 3 rounds at 2.499 2.498 2.501 and 2.502 inches.You will get an hour glass affect at your best seating depth but it will open up quickly on either side.
A quick check of base to ogive length will really open your eyes up on out of the box unsorted vld type bullets.
Right now the Clay Spencer 103's and the Berger 105 BT Match are both shooting very well.Nothing at all wrong with a tangent ogive bullet for 600 yard shooting in my opinion.
Lynn aka Waterboy
 
Reply

Thanks Lynn. I've got some load development to do for sure. When I was working on Dasher load development a few months ago, I may have had a better load than I thought. I'll let you know the results hopefully next week.
 
Tcombest
My father and I are shooting a pair of 6Dashers in lightgun and I have a 65 pound all aluminum stocked heavygun in 6Dasher.Our reamer has 0.103 - 0.105 freebore as I don't have it sitting here in front of me right now.
We are using 33.1 - 33.5 grains of RE15 and a CCI 450 Magnum primer.My father shot the 4th smallest group at the NBRSA 1000 Yard Nationals and I shot the 5th smallest group and we did it with unsorted berger 105's that Lou Murdica had sitting in one of the compartments of his motorhome.I had a press bolted to my trucks receiver hitch and we loaded from a motel room.
Those bullets had very consistent bearng surface lengths.
Anytime your seating depth varies more than 0.003 when using a good comparator your groups suck.
Load up 30 rounds at your best powder charge and seating deopth.Then using your comparator group all the rounds that are spot on in one bunch and shoot a couple groups.Now use your widely spaced rounds and repeat.
On your shortrange guns using custom bullets you probaly don't get very much seating depth variation at all.On your longrange gun you probaly do.
Waterboy
 
Here is my question: When you shoot the 1:8 twist guns that are set up for long distance, can you really expect to be able to tune them to shoot consistently tiny groups like the 6ppc or 30br? Or should you be satisfied with a 0.2-0.4" group?
Click to expand...
I'm with Al on this one. I too shoot both point-blank and 1K, but most recent PB shooting is all score.

That said, I think you're right on the edge with your .2 question. I have shot three successive targets at 100 yards, match style, with a 6mm and 106-grain bullets. The agg (5 shots each target) was a flat 2. This was not a Dasher, but a 2" PPC. With our big .30s, we get flat 2s as well.

Ferris Pindell made a statement that if he were competing today, he'd use a 6-BR with "long-range" bullets for 200 yard PB group shooting, and made a meplat closing die to show the setup.

One thing I've noticed, as I also tune loads at 100 yards, is you have to allow for drop (vertical) growing exponentially at long range, whereas horizontal grows arithmetically. You can see this in ballistic charts.

So a .170 at 100 yards where that is all vertical will not stay that small. When you get a small one at 100 that is all vertical, it is apt to be quite a bit larger at 1,000. A .170 that is all horizontal will translate out to 1,000.

I'm being awfully general, but the question was general too. I don't happen to shoot either the 6BR or 6.5/284, but have used chamberings I think close enough. Lynn has pointed out some things he's found critical. My current kick is ignition, I've found things with primers that sometimes don't show at 100 that do seem a factor at 1K. Yes, of course ignition is all about vertical, that damn gravity being exponential.

Back to Al's response. If you can't agg a flat 2 at 100, you're apt to get beat. As we learn more, it's only going to get worse.
 
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