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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/22/2009 at 21:04
blmfgym View Drop Down
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Is there any data anywhere that would help me read and analize group patterns that I shoot and help me change my powder load, bullet selection, OAL, etc.?
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/22/2009 at 21:42
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Nothing does all that, no.

Add to the mix that you might pull your shots to the left or might have the yips one day, it gets complicated fast.

I recommend a very, very solid rest from which to load test (see what the round is doing rather than what you are doing with the round), and make a few variations of similar loads, change the powder charge in 0.2 or 0.5 increments to see what the rifle likes.

Also, experiment with different primers and projectiles - but only change one thing at a time, don't test new projectile, primer, and powder all at once, too many variable.

I tend to find a bullet I like then try a few powders at different velocities.  Once I figure out what shoots well, I look at improving things with primers and weight-matched brass.

With my go-to .308, I had such great luck with one recipe, I never did any more development, ol' girl shoots great with the first one I tried: why fix what ain't broke?
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/22/2009 at 21:43
Roy Finn View Drop Down
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Are you referring to a guideline to help you shrink groups? Not sure I completely understand what it is you are looking for. Group patterns, such as vertical stringing and horizontal shifts can be attributed to many things such as a barrel heating up, bedding issues and inconsistent hold techniques. For the most part, shrinking groups, for me anyhow, has been a trial and error affair.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/22/2009 at 21:53
Monster View Drop Down
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It's called the OT! Tke detailed notes at the range and post them here and you will most likely get a response to help you tighten up those groups Thunbs Up
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/23/2009 at 03:54
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Originally posted by blmfgym blmfgym wrote:

Is there any data anywhere that would help me read and analize group patterns that I shoot and help me change my powder load, bullet selection, OAL, etc.?
 
I recently did a lot of fine tuning on a particular rifle and found that as the pressure increased (more powder or shorter OCL) the bullets would show vertical stringing. As the pressure dropped off (less powder or longer OCL) the group would close up and eventually go into a horizontal spread.
It became so consistent that I could just look at the vertical spread or horizontal spread and new which way to go in order to close up the group.
 
Not sure if this is the type of info you are looking for?
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/23/2009 at 08:51
Dale Clifford View Drop Down
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be realistic in your expectations of what the gun and equipment can do under the conditions you are shooting.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/23/2009 at 21:21
sakomato View Drop Down
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The only place I know of that gets into analyzing groups is the OCW site
 
 
where they analyze groups according to the Optimal Charge Weight
 
 
sorta like reading tea leaves but there are a few good things to learn.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/25/2009 at 09:19
blmfgym View Drop Down
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I love Monster's visuals and appreciate all of your responses.  * shot hit on what I've observed from shooting quite a  bit. I think you thoughts are what I was looking for Also, I'll check out Sakomato's web addresses.
Thanks again.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/27/2009 at 20:38
blmfgym View Drop Down
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I really appreciate your web site information. I have studied his ideas and can definitely see where he got his information. I'm going to try it at the range. Thanks again.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: June/27/2009 at 21:56
Mike McDonald View Drop Down
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Well..........I'll have a go at it, maybe it'll make some sense.
 
Rifle, not mine, shooting factory and hand load ammo
 
Both groups are consistant but exhibit some lateral movement.  Rifle or shooter?
It was brisk so I'm going with the shooter as the error.  Subseqent use of the same ammunition showed more consistant grouping, it  was in fact the shooter causing the error.  Like the Monster said, NOTES AT THE RANGE so ou cancompare targets days/weeks/months later.
 
Next up, my 260 palma rifle
No errors in this group, it just does that consistantly.  Any deviation IS the shooter.
 
1000 yard group, would you take  this as good?
 
It's not.  Previous and subsequent NOTE review ( there's a theme starting )
Shows the ammunition and rifle capable of producing groups with much less vertical dispersion, almost 2/3 less in fact.  Shooter error.
 
So you can see why at this point not too many folks are chiming in. This is as much art as it is science and there's not enough data about your experience, your equipment, or your ammunition and it's history to offer meaningful advise.......other than TAKE RANGE NOTES! Emoticons
 
Good shooting
Mike
 
 
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/21/2009 at 20:54
blmfgym View Drop Down
Optics GrassHopper
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I appreciate all of the responses. I have since experimented with my Rem. 700 300 WSM and found on different days the groups were entirely different. I was checking an old load of 66 grains of IMR 4350 with Sierra Gameking 165 BTSP and a new load I was working with 71 grains REloader 22 both loads set at 2.800 OAL. On day 1 I coildn't seem to shot any decent groups at all. However, on day two after checking my calipers, scales, brass, etc. I shot a less than .75 group with the IMR load and less than a 1" groups with the
Reloader 22 load. So I agree with the shooter error and condition changing can cause totally different groups. All of your answers were very helpful. My main trouble I'm having now is trying to find a load my Rem. VTR 308 with shoot. I've tried several powders ( Imr 4350,4064, 3031, Varget, H4350,and H380 and unsatisfactory results. I've started at the low load and worked up trying different loads at different lengths if the a reciept looked promising to no avail. I haven't had the barrel bedded yet but I have had the trigger fixed to 2.5 lbs. from 7 from the factory. I also tried the Tubbs final finish ti lap the barrell but the improvement wasn't satisfactory.
To All.    Any suggestions?
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/22/2009 at 03:36
sakomato View Drop Down
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Lately I've been working on making my bullet grip and seating depth absolutely consistant.  Notice in the following pics how the POI moves around the target as the seating depth changes
 
what that tells me is that if my seating depth changes from one shot to the other then my group size will increase because of this changing POI.
 
Seating depth will vary unless you are very carefull with making the bullet grip the same.  IOW if you are seating bullets in a bunch of prepped and charged cases, if the inside neck has a slightly smaller diameter or varies in smoothness, then it will not seat to the same OAL.  Even though you have the seater locked down, if one bullet is harder to seat in a case then the previous one, the one that felt harder to seat will have a long OAL.  Don't believe me then measure one that seems harder to seat compared to another one that seats easily.
 
Also the more bullet grip the greater the variance in seating depth.  To get around this I size mostly with the Lee Collet Neck Sizer which produces very low bullet grip (usually .001"), steel wool the inside of the necks, lube the inside of the neck with Mica and use a Competition Seating Die (RCBS or Redding).  Doing this, the amount of force necessary to seat the bullet is much more consistant and the OAL is also very consistant.
 
IMO, the closer you seat to the lands, the more critical it becomes to have an absolutely consistant seating depth.   IOW, with a long jump like on a Weatherby caliber, the seating depth consistancy is not as important as a rifle where you seat <.020" off the lands.
 
Since I have started steel wooling
 
and lubing with Mica
 
my seating depths have been within .002" of each other and velocities have stabilized.  My last 6 shots with my 338RUM chronographed 3191, 3182, 3182, 3189, 3189 and 3197 fps and it has lead to groups like this
 
where every one of these shots chonographed 3072 fps.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/22/2009 at 07:14
RONK View Drop Down
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 Sako- you pay more attention to detail at the loading bench than anyone I know.

 And it shows.

 Good work, Man!

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/22/2009 at 11:49
RifleDude View Drop Down
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No kidding!  I don't have the patience for that level of prep.  I hate prepping brass!  I'd rather be whipped with a cat of 9 tails than spend more than 15 consecutive minutes turning necks, trimming, reaming, chamfering, etc. cases!  Consequently, I reserve the more extreme brass prep measures for my precision rifles, and typically do only the bare minimum prep required for my big game rifles.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/23/2009 at 10:09
safariarms man View Drop Down
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Originally posted by RifleDude RifleDude wrote:

No kidding!  I don't have the patience for that level of prep.  I hate prepping brass!  I'd rather be whipped with a cat of 9 tails than spend more than 15 consecutive minutes turning necks, trimming, reaming, chamfering, etc. cases!  Consequently, I reserve the more extreme brass prep measures for my precision rifles, and typically do only the bare minimum prep required for my big game rifles.
I am one to agree.  I try to do all of the things right, but I have been very fortunate in my endeavours.  I typically load about 0.02 off of the lands and grooves and have been very successful with all of my good quality rifle with less than moa and some that I have accurized of custom or semi-custom built to much better than that.  I read an article on the 22 Hornet regarding using small pistol primers and I may try that, as my groups that, my groups with my Savage model 40 are about 1.5 inches on a regular basis with factory or my reloads to 0.02 to 0.04 off of the lands a grooves.  Funny thing is, first time I reloaded for, I placed a cartridge in the chamber to make sure it chambered well, but it was too long to eject through the small port.  Well needless to say, I had to shoot it against a solid wooden back stop with good ricochet protection.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/24/2009 at 20:30
blmfgym View Drop Down
Optics GrassHopper
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Thank You. Good information.
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