New load development for 6xc

[DLT]

My 6xc still shoots ok but according to the bore scope I don’t want to keep pushing expensive Berger bullets through it. I have 400 Barnes 112s and and as many Sierra 107s. I’m going to try and do a load dev. by narrowing down the seating depth first, then move to power. Since my barrel is clean it won’t take much to find my touch point. I’m thinking about starting at .020 in from touch then backing out. How many thou should I move it for each group ? .005 ?.010 ? More ? Thanks men

 

[urbanrifleman]

My 6xc still shoots ok but according to the bore scope I don’t want to keep pushing expensive Berger bullets through it. I have 400 Barnes 112s and and as many Sierra 107s. I’m going to try and do a load dev. by narrowing down the seating depth first, then move to power. Since my barrel is clean it won’t take much to find my touch point. I’m thinking about starting at .020 in from touch then backing out. How many thou should I move it for each group ? .005 ?.010 ? More ? Thanks men

Barnes 112 20 jump
R16
No load workup.
38.5/39.5
My 8 twist.

38.5 was the left side groups.

 

[DLT]

Barnes 112 20 jump
R16
No load workup.
38.5/39.5
My 8 twist.

38.5 was the left side groups.

View attachment 1656928View attachment 1656929View attachment 1656930View attachment 1656931

Ehhhh. I have a little r16 and a pile of h4350. If I can’t make it work first I’ll try the 16. It’s hard to find and expensive when you do

 

[Idaho-Lefty]

My "Pet" 6 XC load, uses the 107 gr. SMK's with about .012- .015 of, Rifling "Jam Marks", all around Bullet, .002 Neck Tension, and 40.7 grains, "Thrown Chg's" of, StaBall 65 Powder, F-210 M's @ just under, 3,000 FPS.
BugHoles 5 shots, from LOW 2's to, 3's when,.. I'm "On".
If,.. "Jamming" the 107's with, H-4350 or, IMR 4350 Back Off,, on the Max Powder chg. 1/2 to, a Full Grain of, Powder after finding,. Max,.. powder / Velocity.
I WAS using, 41.2 gr StaBall 65 with, .020 "Jump" then, went to Jamming the Bullet and the Group's,.. SHRUNK,.. Noticeably !

 

[urbanrifleman]

Ehhhh. I have a little r16 and a pile of h4350. If I can’t make it work first I’ll try the 16. It’s hard to find and expensive when you do

H4350. Same thing. I am pretty sure they will behave almost exactly the same.

Most of my customers are using h4350 and we basically interchange loads in the 6XC.

 

[urbanrifleman]

Ehhhh. I have a little r16 and a pile of h4350. If I can’t make it work first I’ll try the 16. It’s hard to find and expensive when you do

From a customer with my barrel. I think it was brand new too.

 

[swd]

107SMK’s love to be in the lands. Put them in until the engraving marks are square. And back off from there. I found more often than not I leave them right there.

 

[mgunderson]

If you have a known load that you are happy with. Try the same base to ogive dimension with the 107 sierra. You might have to tweak a few thousandths in or out but you should be close.

Can't speak to the Barnes bullets. My apologies.

 

[Bill Norris]

My 6xc still shoots ok but according to the bore scope I don’t want to keep pushing expensive Berger bullets through it. I have 400 Barnes 112s and and as many Sierra 107s. I’m going to try and do a load dev. by narrowing down the seating depth first, then move to power. Since my barrel is clean it won’t take much to find my touch point. I’m thinking about starting at .020 in from touch then backing out. How many thou should I move it for each group ? .005 ?.010 ? More ? Thanks men

I feel .002 to .003 per increment would be better with seat depth changes.

 

[mikecr]

You need to pick a bullet for your seating testing.
Each will have it's own optimum in your barrel.

I roughly follow Berger's recommended seating testing.
Back off charge from any powder node (as estimated), big change increments, then small window increments, final tweaking later (after powder development).

 

[DLT]

Did not get the 107s and H4350 to shoot well at distance. Changed primers and moved to R-16. Charges were 38.0, 38.4, 38.8, and 39.1. My point of impact stayed the same and my numbers were great. What would you try next ? Seating in small increments ? Groups was shot at 100yds

 

[JLT]

Did not get the 107s and H4350 to shoot well at distance. Changed primers and moved to R-16. Charges were 38.0, 38.4, 38.8, and 39.1. My point of impact stayed the same and my numbers were great. What would you try next ? Seating in small increments ? Groups was shot at 100yds

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Shoot the 38.4 load with seating depths starting at .015" into the rifling from touch and work out in .003" increments. Three round groups are good enough to get an idea of where to look for repeatability. Shoot the groups at 100 yards - less noise from atmospherics. Take the picks of the litter and shoot a couple of five shot groups for each to validate.

As others have said, I wouldn't be at all surprised if you stayed with .015" in with the 107s.

 

[J_idaho]

Barnes 112 20 jump
R16
No load workup.
38.5/39.5
My 8 twist.

38.5 was the left side groups.

View attachment 1656928I just wanted to say I love the color of your rifle. The force is strong with this one.

 

[urbanrifleman]

That's the Schoolbus.

 

[mikecr]

As others have said, I wouldn't be at all surprised if you stayed with .015" in with the 107s.

If you're powder developed while into lands, and tweak seating off lands, the powder node will collapse as pressure tanks, messing with your seating test. Then, no seating beyond is going to pull you back into that powder node.
So then it seems like the seating you pulled out of your butt to begin with just happened to be best.
But there was never a reason for it to actually be best.

 

[urbanrifleman]

Did not get the 107s and H4350 to shoot well at distance. Changed primers and moved to R-16. Charges were 38.0, 38.4, 38.8, and 39.1. My point of impact stayed the same and my numbers were great. What would you try next ? Seating in small increments ? Groups was shot at 100yds

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Honest question.

You believe that loads fall apart at distance (even with single digit spreads like you are showing) but will perform well at short range?

 

[DLT]

Honest question.

You believe that loads fall apart at distance (even with single digit spreads like you are showing) but will perform well at short range?

Honest answer. I can’t swear it wasn’t me or the wind or the load. But i usually have much better luck where we were shooting. I noticed a lot of verticle going on this past Sunday. Winds were coming and going. The most sane thing to do would be to wait until early morning and shoot and seen how it did in much better conditions

 

[JLT]

If you're powder developed while into lands, and tweak seating off lands, the powder node will collapse as pressure tanks, messing with your seating test. Then, no seating beyond is going to pull you back into that powder node.
So then it seems like the seating you pulled out of your butt to begin with just happened to be best.
But there was never a reason for it to actually be best.

It is not a closely guarded secret that 107s like some contact with the rifling.

 

[JFrank]

Did not get the 107s and H4350 to shoot well at distance. Changed primers and moved to R-16. Charges were 38.0, 38.4, 38.8, and 39.1. My point of impact stayed the same and my numbers were great. What would you try next ? Seating in small increments ? Groups was shot at 100yds

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How about shooting a real ladder test that covers multiple charges from low to pressure signs at 300 yards or so, rather than these little four charge groups at 100.
As posted above , pick a bullet and learn what it likes and develop a load. Just trying different things will just keep you chasing your tail.

Jim

 

[DLT]

It is not a closely guarded secret that 107s like some contact with the rifling.

How about shooting a real ladder test that covers multiple charges from low to pressure signs at 300 yards or so, rather than these little four charge groups at 100.
As posted above , pick a bullet and learn what it likes and develop a load. Just trying different things will just keep you chasing your tail.

Jim

I should have went lower on starting charge but I did have one slightly snug bolt opening at 39.1. I feel good enough to try at 200 but I don’t feel I could be consistent enough with my setup and glass for 300