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Precision Bolt action gurus, some advice on my rifle, please (update) Login/Join 
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Picture of barndg00
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So, I have a Savage 10 receiver that I'm trying to get the best accuracy I can out of with its current setup. It began life as a "Predator Hunter" model in .243 Win. A year ago, that barrel was pretty well shot out, and I decided to make some upgrades. It now has a Shilen Select Match barrel in 243 Win, with Northland Shooters recoil lug and barrel nut and I've placed it in a Choate Custom Tactical stock, properly torqued to 65 in#'s. I've worked very hard with reloading - using Berger 105gn bullets (tried both VLD and Hybrids), loads trickled to 0.02gr on my GemPro scale. All that to say I'm really trying to make this thing shoot really well.

Currently, I only shoot to 200yds, the most I have access to easily and I'm getting groups between 1.5-2" regularly with that, but at times am getting better, best was 0.958" yesterday. However, at times I get flyers that expand the group to 2.5", that I can't seem to explain with my shooting (not to say that that's not possible, or even most likely).

My current concerns - the scope base is a 2-piece set up from the factory. Would I be likely to benefit from going to a 1 piece base? If so, should I bed that base to the receiver? Also, would the stock benefit from skim bedding, it does have a full length aluminum V-block. Or am I at the limits of this equipment, and should not put any more money or effort into it and enjoy my almost "all-day, everyday MOA rifle". Thanks for your help!

This message has been edited. Last edited by: barndg00,
 
Posts: 2155 | Location: NC | Registered: January 01, 2006Reply With QuoteReport This Post
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Are you checking your bullets for runout? When I had that problem, I found 1 out of every 4-5 bullets were about 7 thousands off of being centered. I learned to properly seat my bullet seating die which solved the problem, now almost all are withing 1.5 thousandths and all are under 3 thou of true center.




“People have to really suffer before they can risk doing what they love.” –Chuck Palahnuik

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Posts: 5043 | Location: Oregon | Registered: October 02, 2005Reply With QuoteReport This Post
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Describe the flyers. Where do they impact relative to the group? Got pictures?
 
Posts: 3398 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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For pictures, I only have my targets from yesterday, which was further working on load development. These are 10 5 shot groups, at 200yds. The first 5 are Berger 105 VLD Target bullets, the last 5 are Berger 105 Hybrid Target bullets. Each group is 0.2gr more power than the last for each set of bullets. There were no scope adjustments made, aimed at the dot for every shot, and don't think wind would have had much effect at all given the range and that it seemed to be coming from behind me.

VLD 42.6 - 1.49"


VLD 42.8 - 0.958"


VLD 43.0 - 1.94"


VLD 43.2 - 2.5"


VLD 43.4 - 1.57"


Hybrid 42.6 - 2.37"


Hybrid 42.8 - 1.88"


Hybrid 43.0 - 2.82"


Hybrid 43.2 - 2.07"


Hybrid 43.4 - 1.27"
 
Posts: 2155 | Location: NC | Registered: January 01, 2006Reply With QuoteReport This Post
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Very good. I think I see what's going on here. I'll give the details in the morning, but I think you have a combination of Ocw and seating depth issues.
 
Posts: 3398 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Never underestimate a tailwind.

Of all the possible winds, when I lay down to shoot a match, a tailwind is the one I dread most.
 
Posts: 15665 | Location: Location, Location  | Registered: April 09, 2012Reply With QuoteReport This Post
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Let me introduce you to the concept of accuracy node. When a bullet exists the barrel it's going to be going where the barrel is pointing at the moment it leaves the bore. When you're igniting a cartridge, there is a sound wave that goes down the barrel. The speed of sound in steel is MUCH higher than the speed of sound in the air and the waves will travel back and forth several times before the bullet reaches the bore to exit.

If the wave is near the bore when the bullet leaves, the barrel will not be pointing reliably the same position every time and you get dispersement of the bullets on target; big groups. As you add powder the speed of the bullet increases and at some point, the bullets start grouping tightly; you are approaching an accuracy node. This is where the sound wave is at the rear of the barrel, away from the muzzle when the bullet exists and the barrel is pointing much more consistently.

From what I see in the pictures, your first load is nearer an accuracy node than the heavier ones who seem to be approaching or are even in a bad node. The shift of the zero is a classic sign of that phenomenon.

What I would do is keep increasing the loads in order to reach the next higher accuracy node and see if you can reach it before going max.

When I look for a node for a new barrel, I usually start above minimum required velocity for my purposes and then load 5 shots in groups incrementing by .5 grains. When I identify a node, I can refine it by playing with .2 grains increments. It's a very quick way to find a node.

You don't care where on paper it hits, you want a small group, at the same elevation.

Once you have that, you may want to play with seating depth for the bullet, and hybrids, VLDs and similar are quite sensitive to seating depth. I use VLDs for my match ammo and from long experience, I seat that model of bullet right at the lands. The fact that your tightest group had one flyer is a classic case of seating depth syndrome. Those are the ones that can drive you crazy trying to figure out if you don't know about seating depth.

I discuss these concepts in some depth in my stickied thread in the loading section.

Of, course, I'm making the assumption that you are a competent trigger puller and that the wind wasn't howling and that you know how about "touching wood" with your trigger finger and are avoiding that.

Of course, I could be all wrong, in which case you can ask me for your money back. :-)
 
Posts: 3398 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Not to try and top the master, but the concept is very valid and used by top shooters (and less-than-top shooters - me) when they work up a new load or a load on a new barrel.

The speed of the sine wave in the barrel steel is around 18,000 fps. The wave has time to travel back and forth from the breech/action to the end of the barrel several times depending upon the load and the barrel length.

The two methodologies Nikon speaks of are Optimal Charge Weight (OCW) and Optimal Barrel Time (OBT) both of which can be found with Google or Bing searches.

Both are designed to help you find the internal ballistics you need to determine the charge weight that will give a given rifle/barre/charge weight/projectile the best opportunity to consistently shoot small groups to the same point of impact time after time not considering external factors such as wind and atmosphere and shooter skill/ability.

It is a fascinating journey that will frustrate you/engage you/madden you if not executed properly.

Have fun and shoot straight.

RMD




TL Davis: “The Second Amendment is special, not because it protects guns, but because its violation signals a government with the intention to oppress its people…”
Remember: After the first one, the rest are free.
 
Posts: 20303 | Location: L.A. - Lower Alabama | Registered: April 06, 2008Reply With QuoteReport This Post
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quote:
Originally posted by rduckwor:
Not to try and top the master, but the concept is very valid and used by top shooters (and less-than-top shooters - me) when they work up a new load or a load on a new barrel.


You know, it's comments like that that make me doubt your sanity. :-)

You cannot be serious with the "master" thing.

And don't try to be humble, I'll have you know that my humility is much better than yours. Smile
 
Posts: 3398 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Picture of barndg00
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Thanks for the replies gentlemen. I originally worked to this charge weight range with the Hornady 105gr AMAX bullet. I used that charge weight as the starting point for these, but now am guessing I need to go back to the drawing board and start from scratch. Do you have any advice on choosing the VLD vs Hybrid bullet? Knowing my cartridge choice is known for more rapid throat erosion, I had thought the Hybrids might be the better choice, but for know, the VLDs seem to shoot better.
 
Posts: 2155 | Location: NC | Registered: January 01, 2006Reply With QuoteReport This Post
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I would add that in addition to the wisdom of the previous posts, one can induce a bit of parallax if you change your focal position with each shot.

Depending on the quality of the optic and your vision, when I see two or more shots out of the group, but more or less in the same area on target, I work on a repeatable cheek weld and position on the stock. You know just to rule out me as the culprit Smile I see this when my 'match load' seems to not wanna play nice, usually it's me.
 
Posts: 1320 | Location: Montana | Registered: October 20, 2007Reply With QuoteReport This Post
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I had a Savage 10 in .223 that always threw one round out of five.... every time! I took the barreled action off to 300 Below and had it frozen. I was not a believer in the process, but had shooter friends of mine that were. Since the place is not far away from me I took it in and it done. I was amazed that it got rid of the flyer. That took care of it for me.

EGW makes some really nice one piece bases. Not associated with them, but I do have several of their bases (both 0 moa and 20 moa).


********************************************
"On the other side of fear you will always find freedom"
 
Posts: 2667 | Registered: January 08, 2009Reply With QuoteReport This Post
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Picture of barndg00
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I'd like to think I'm doing ok as a trigger puller, though this is my only real precision rifle. But I'm not sure what the "touching wood" with my trigger finger means.

I read the OBT article, very interesting stuff. It did make me go ahead and buy a copy of QuickLoad, something I've been interested in for a while.
 
Posts: 2155 | Location: NC | Registered: January 01, 2006Reply With QuoteReport This Post
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You make it difficult to help you by not providing a lot of information. We don't know the barrel length, nor do I see the powder used.

I'll give you the cliff notes of my stickied thread this way: Visit the web site of the powder manufacturer. From there, select the starting load for that bullet weight as well as the max load. Do not exceed the max load at this time. From the starting load, create sets of 5 cartridges in .5 grain increments, until you reach your maximum.

Clean the rifle really well, then go to the range with your loads and an extra 3-4 cartridges loaded minimum with the same powder.

Set up a target at 100 or 200 (doesn't matter) with as many aiming points as you have loads. I usually have something like 5-6 loads and I use a big cardboard on which I put 5 or 6 dots.

Run the extra rounds through the rifle to foul the barrel.

Now starting with your minimum load, shot one round from each set of cartridges on the equivalent target, in round robin fashion.

So, let's say you have 5 loads and 5 targets: Target 1 is load 1, target 2 is load 2, and so on to target 5 for load 5.
Shoot 1st round of load 1 on target 1.
Shoot 1st round of load 2 on target 2.
.
.
Shoot 1st round of load 5 on target 5.
Shoot 2nd round of load 1 on target 1.
Shoot 2nd round of load 2 on target 2.
...
Shoot 5th round of load 4 on target 4.
Shoot 5th round of load 5 on target 5.

Now look at the groups on target. You're really looking for the group or groups where the bullet holes are at the same elevation (waterline) and closest together. If at 200 yards with wind, waterline beats smallest group.

You might find 2 or 3 groups that show great promise, you could pick the average load of these groups or you could do another round with loads .2gr between the top and bottom great loads and see if you can pick something really special.

I've never load Hybrids, I don't use Berger bullets. That said, the hybrid was designed to be easy to find the proper seating depth. VLDs can be finicky because of their secant ogives; I load seat them at the lands.

Touching wood is when your trigger finger actually touches the stock (wood) of the rifle as well as the trigger. That will destroy accuracy; your trigger finger must only touch the trigger.
 
Posts: 3398 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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quote:
Originally posted by NikonUser:
Touching wood is when your trigger finger actually touches the stock (wood) of the rifle as well as the trigger. That will destroy accuracy; your trigger finger must only touch the trigger.

Whew. I was hoping you'd respond with that, as opposed to cueing up the bow-chicka-bow-wow music.
 
Posts: 7853 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
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Thanks for the description, Nikon. That is actually exactly how I'd been proceeding prior to these loads you had seen, the difference being that I switched to the Berger bullets b/c I was not happy with the performance of the AMAX bullets. I took the best charge weight for that bullet, since they were all 105gr, and used it as the starting point for my Berger loads - perhaps this was a mistake. That's why these loads only have 0.2gr variance rather than the more typical 0.5. The VLD's were loaded 0.01 into the lands, the Hybrids 0.01 off the lands.

As for the rifle - 243Winchester, 26" barrel, Lapua brass, H4831SC powder - weight listed above with the pictures. Winchester Large Rifle primers, seated at 2.270" CBTO (Cartridge base to ogive) for the VLD, 2.328 CBTO for the Hybrids. No, I don't let my trigger finger touch anything other than the trigger.

43.5gr is listed as max from my research, I did not see pressure signs at that level in previous loads with the AMAX bullets.

Any more information that would be helpful, please just let me know, I keep most everything recorded, and do have some chrony data as well, but was not able to set it up for these particular loads due to the range at the time.
 
Posts: 2155 | Location: NC | Registered: January 01, 2006Reply With QuoteReport This Post
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quote:
Originally posted by fritz:
quote:
Originally posted by NikonUser:
Touching wood is when your trigger finger actually touches the stock (wood) of the rifle as well as the trigger. That will destroy accuracy; your trigger finger must only touch the trigger.

Whew. I was hoping you'd respond with that, as opposed to cueing up the bow-chicka-bow-wow music.


LOL
 
Posts: 3398 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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43.2, 43.4 Hybrids don't look bad. The horizontal could be you? I would keep going up in charge, obviously watching for pressure.

Suggest to stay with the jump friendly Hybrids. You'll be moving the VLD's constantly chasing the throat.

243's around me are all loaded with 47.5-49 H1000/Hybrids/Magnum primer.
 
Posts: 3197 | Location: 9860 ft above sea level Colorado | Registered: December 31, 2008Reply With QuoteReport This Post
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Picture of rduckwor
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quote:
You know, it's comments like that that make me doubt your sanity. :-)



If I EVER shoot your AVERAGE score in an F-Class match, we will get together and discuss whose humility is superior.

I will buy the libations for this occasion.

RMD




TL Davis: “The Second Amendment is special, not because it protects guns, but because its violation signals a government with the intention to oppress its people…”
Remember: After the first one, the rest are free.
 
Posts: 20303 | Location: L.A. - Lower Alabama | Registered: April 06, 2008Reply With QuoteReport This Post
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So, my life has been quite busy the last few months, but I was able to finally get my rifle to the range with new loads after all the prior discussion. Things are much improved I believe.

Today, I shot 3 new loads each for the Berger 105gr VLD and Hybrids. I used Quickload to determine the charge weights for optimal barrel times. Interestingly, Quickload was right at 200fps slower than my barrel, something I need to figure out.

Specs: 243Win, 26" barrel 1:8" twist, Lapua brass, H4831SC powder, 200yd 5 shot groups shot round robin style.

Hybrids:
39.50gr - 2790fps (2587 predicted) - 1.96"


42.54gr - 2983fps (2787 predicted) - 1.70"


44.28gr - 3069fps (2899 predicted) - 1.8"


VLDs:
39.36gr - 2783fps (2583 predicted) - 1.07"


42.38gr - 2975fps (2779 predicted) - 1.04" The upper shot in the paster was actually from the 3rd VLD string, my mistake while shooting these round robin, it was transposed to the 3rd string for measuring.)


44.06gr - 3097fps (2891 predicted) - 1.16"


I'm very happy with the VLD numbers. The hybrids just don't seem to shoot as well, though given the QL numbers were so far of, and so consistently off for all the strings, I'm not sure what to make of it. Any ideas for improving QL's accuracy? Thanks! I'll try to update this post with pictures of the groups later.
 
Posts: 2155 | Location: NC | Registered: January 01, 2006Reply With QuoteReport This Post
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