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Long range load development at 100 yards.

[QUOTE author=Colo204]
Erik,
Thanks that was really help full, just want to make sure wioth you that I understood what I read [LR development at 100 yards]…
Load test round in .3g -.5g increments shout them at the same POA. Those that have the same POI in the x and y are considered the best node for that powder and bullet combo?
Retest to confirm the powder node
Then…
Further tune with seating depth from Jam, which appears to .015 into the lands, to working in .003 increments heading away from the lands. Am I understanding it so far?
[/QUOTE]

You are looking for groups that impact the same vertically, don't worry about horizontal too much at this point.

"Jam" and "into the lands" are two different things. Jam is the point where the bullet will not go into the lands any further. I find that point by seating a bullet long and applying die wax to bullet ogive and closing bolt (no firing pin) on round, then snap bolt open and measure new seating depth. This is known as "Jam".

I stay at least .010" away from "Jam" and work away from there in .003" increments.



[QUOTE author=Colo204]
So question
1. I plan on trying 105 vld and hybrid and the 108 match, plus the Lapua 105 sc. Do I start them all in the same position…meaning with a jam, .015 into the land? Then back them off in .003. or does each one of these bullets require a different starting/jam point?

2. Is there typically a starting sweet spot for the bullets mentioned above?

3. Should I test 3 or 5 shot groups at 100? 3 save money, time, and barrel life?

4. What is the barrel most sensitive to…powder charge or seating depth?

5. Do different bullets in the same weight range tend to shoot accurately in the same velocity node
[/QUOTE]


1. Start them all at the same point.
2. No, some guys have luck with them at a certain point, but to find the best seating depth for your rifle, you must do the entire test.
3. Three shot groups is plenty at this point.
4. Both. If you are at the edge of the window, both can give you huge groups with small change, when in the node, neither will give you noticeable difference with small change.
5. Make no assumptions, you must test each thoroughly in your rifle to find the best load.
 
Never had a barrel that shoot great groups out of the gate. This was a guess of optimal seating......

Are barrels suppose to shoot bugholes with first guess of seating depth and powder charges??

This was initial powder charge testing.
 
Here is one from yesterday afternoon on my 284 shehane with a krieger 5R that is being slightly painful with copper fouling and being hard to figure out in general. The shot low on the 55.1 charge was out of that group as the buddies I was shooting with at the time hit the piece of paper low where it was fixed to a cardboard box and it ended up swinging down on the right corner a little before I shot. So that shot would have hit into the others. (Ive cut their groups away so you only see mine). Two shots top left were sighters. To me I would say 55.1-55.7 would be my node but happy to be corrected. Bullet was a moly coated 180gr berger VLD 10 thousandths past touching the lands. No velocities as I havent got the magnetospeed with me at the moment, however on a past test with 180 hybrids, 55gr of powder produced avg 2890fps with naked 180 hybrids jumped 15 thousandths. I can only assume (which is not the greatest idea) that these loads would have been running between 2850 and 2950fps.

 
Thanks Erik. I wont do any chrony work until I get a decent result on target. There is a 500m club match on this sunday which will be perfect. Will shoot some 10 shot strings on electronic targets and get a good idea of how they group.
 
Thoughts. Erik this look better ;D. I wish I would have had 43.1 just to help see better. Amazed at how well these shot so far(groups no bigger than 0.3") and wind was kinda switchy with 5-8mph winds

 
no #s. Friend who has magnetospeed was working today. This look like a good enough barrel to put your tuner on? We talked before about making sure it was a shooter before we did anything on it
 
Another one this time for my 6 dasher 300-600yd f class gun. Shot round robin style, the second shot on each group seemed off and I put this down to a few swirling gusts of wind coming through- strong enough to pick up dust on the range. This was 31.6gr to 32.2gr H4895. Berger 105 hybrids jumped 50" and BR4 primers. It would be very easy to assume 31.6 is right and stop load development (even with the wind causing the flier) but Im thinking more along the lines of 31.7 and playing with seating depth (going closer to the lands). From discussion this seems to be in the region for an accuracy node with H4895 but again no velocities as I dont like the magnetospeed on while shooting groups.

 
So I had limited time and horrible conditions. It was pouring rain on me! Really bummed me out as I was so excited to get out and shoot. I only tested XBR 40-42 grains. 175 smk's, new lapua brass. I think I need to try some more loads with a higher charge weight. I had no pressure signs at all. Let me know what you guys think. I recently read that XBR is best used with 155's so maybe I will just work up a "just in case load" and focus on 155's. Thanks for the help!!!
 

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Re: Long range load development at 100 yards. 22 Feb 14

Well, I tried this today with my new and only just broke it in this morning 6mmBR. Here are the conditions and target. I just want to confirm the right choice. The target was placed horizontal. Low charge is 29.0 to a high of 30.6 grains of Varget, 95gr Berger VLD, CCI 450 primer. Shot left to right then next row left to right. Not sure if I should go a little hotter. NO pressure signs at all. I was going to load some on the lower side but I had Grandpa duties and it's impossible to load with a 2 year old running around !! So this is what I had loaded this past Thursday evening. Some of the ones that are out was a missed lull in the wind. Same hold for all shots.
What do you think ??

Thank you again Erik for this great thread !!
Rmist
 

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Just testing out my new 280AI. Powder used is H4831SC, Nosler 280AI brass, BR2 primers and 180 Hybrids out of a 32" barrel with 52 rds. thru it after testing. Temps were 55 to 65 DEG. I also used once fired brass as foulers to see what the difference was between virgin and fired brass.

I would also like to thank Erik for his contributions to this thread and the shooting community. He has been my long distance coach, mentor, and great load developer over the phone !!!
 

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DrDr, nothing conclusive from your target. Try going hotter like you said and see how it does. Watch for pressure signs and be safe.
 
Lawrence, I think the small group is what I would go with for now since ES is good. Nothing seems to level off, but try that load for now and adjust seating depth. After you get your brass fireformed, run test again to see if barrel settles down.
 

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