I don't know if these Barnes Match Burners are, but I'll find out. Berger says you can jump their VLD bullets and they will shoot well.Originally Posted by charlie b
I Greave so for those who insist that they NEED a MAGAZINE LOL, LOL, LOL !!!
Yes, everyone’s VLD’s can have nodes in the lands, and out of the lands. Last seating depth test I did, I found accuracy at Touch, and from .060” to .080” off the lands. This with Berger Hybrads.
My experience with Bergers was limited to the 155 Full Bore. It really needed to be touching the lands to get the best from it.
The most interesting seat test I did was with 168SMK's. They were good from .060 to .010. But, they did not like to touch.
I hand feed all ammo when I want accuracy, like you, I'm not in a hurry so loading one at a time is fine.
I loaded 18 rounds of Barnes Match Burners with 42 grains of RL-16 and three different seating depths like Barnes recommended. I skipped the load into the lands since I essential already did that and was very pleased with the result. I will shoot these this week to see if there's something that might be better than the results I achieved with 42 grains loaded to the lands. I don't know that I need to spend a lot of time doing this because, except for the load .120 off the lands, none of them will come close to fitting the magazine at that length. Unless one looks like it'll shoot sub half inch groups I'll probably just go with 2.300 CBTO and a COAL of close to 2.950. Even at that length, there is plenty of bullet left in the case.
- 010 into (touching) the lands (jam) 6 rounds
- .040 off the lands (jump) 6 rounds
- .080 off the lands (jump) 6 rounds
- .120 off the lands (jump) 6 rounds
There's one other reason to not shorten the bullets to fit in the magazine. I bought a Redding Competition Seating Die set with a micrometer adjustment and I think some of the results I've achieved the last few weeks are due to that die. For those of you not familiar with it, Redding utilizes a sleeve that slides up as you seat the bullet, guiding and centering it in the case. It also has a spring loaded seating stem, specifically designed for VLD bullets. I've gotten really good results the last couple of trips to the range and believe that some of it is attributable to this die. The issue is, it comes with a warning from Redding that you can't use it on compressed loads.
"To hold the bullet concentrically, the Bullet Alignment Bore and the Seating Stem have been honed and ground to virtually the same diameter as a jacketed bullet. As a result, the seating stem walls are relatively thin and not as inherently robust as the Seating Plug in a standard Seating Die. Though the Stem is heat treated to make it as strong as possible, it will not endure the excess seating pressure of Compressed Charges. This excess seating pressure will crack the Seating Stem which will, in turn, damage the other internal parts of the Die. Please be mindful because replacement parts are costly and NOT covered under Warranty. Please remember that your Competition Seating Die is a precision instrument and should be used and treated as such. A handloader using this Die to compress powder is tantamount to a machinist using a Micrometer as a C-Clamp."
I've been doing calculations and my loads at 2.163 are compressed loads. Here's the math, the numbers on the left of the case and bullet are measured lengths. The numbers on the right are best guesses. I measured the distance from the case mouth to the top of the powder with a 1/4" dowel, marked and measured it with the calipers. I transferred that measurement to the case and took the other measurements by holding the calipers up against the case and eyeballing it. They aren't exact, but close enough to determine that if I load the case to 2.163 CBTO, considerably more than .473 of the bullet is in the case.
I took the die apart and it doesn't look like I damaged anything yet, but I need to figure out how short I can go before I start compressing powder for each bullet I load. I think this only pertains to extruded powder like RL-16 and H4350 because ball powders settle better in the case.
what does 1.9” indicate?
1:9 twist or faster.
Ah, thanks!
The 1:9 is actually wrong. I guess at one time it was, and they just left the old picture of the box. But on Berger’s site, the minimum twist for the 140gr VLD Target is 1:8. The bullet is 1.387” OAL & .718” Base to Ogive length. I am fond of these pills.
Actually, 9 twist is correct for minimum. 1.3 as calculated, is your base minimum. It will
do that at 2700 fps.
Keeping my bad Karma intact since 1952
Fuj', can you explain what 1.3 as calculated is referring to?
With an almost 1.400” long bullet?Even Berger changed this. Just read the listing on their site. I don’t make this stuff up. Now, I’m not saying 1:9 won’t work. And pushing those 140’s at 3000fps+ would certainly help stretch that 1:9. But given the two as choices as choice, I’d choose 1:8 & wager it’s a much better fit. Berger & about every 6.5mm shooter agrees.
Let me ask you Fuj’.. which would you choose, 1:8 or 1:9? Shoot! I’m planning on 1:7.5 next barrel.
This is Ernest T’s thread. And His rifle has a 1 in 8 twist. So 1 in 9 is sort of a Moot point in this instance.
Yeah, I just wanted to know what it meant since I hadn't seen it on other bullets, or at least didn't notice it. Now that I know what it is it makes sense. I'm still interested in understanding how '1.3 calculated" relates to twist.
Not 100% sure, but I think 1.3 is referring to the length of the bullet in inches. Stabilization is subject to bullet “length”. Shooters talk about it in terms bullet weight, but that only applies as it assumes a heavier bullet is longer. Solid copper bullets are longer for their weight, there fore need more twist to stabilize (an example).
The Miller stability calculators used by JBM and others list the stability numbers as 1.3 as the
minimum and 2.0 as maximum. Simply put, under 1.3, you run the risk of key holing and over
2.0, would mean over spinning and possibly blowing bullets up. JBM is a free online calculator.
Very simple to use. I have several I use, but JBM is quick when checking stabilities.
And Mr. Hoback.....Why would I recommend a twist without knowing the bullet and speed you'll
be dealing with. If your ordering up a 1:7.5 twist, that's fine if you did the math.
Keeping my bad Karma intact since 1952
For the most part I rely on the bullet mfg to determine twist for stable bullets....BUT....it is not written in stone. The muzzle velocity is a large factor in this. Drive a bullet 100fps faster and the spin rate is that much higher with a higher stability factor.
Keep in mind the Miller stability equation is a simplification of the basic stability equations. The main points are they assume a bullet profile that looks like a football and the velocity range is intended to be near Mach 2.5. The fine points of bullet design can make the calculated number off a bit. It is a good guide, but, again, not definitive.
Working with Sierra 77SMK's in 1:9 twist barrels. Sierra recommends 1:8 or faster but the 1:9 works in many rifles, at least when the velocity is closer to max. Maybe if you use a 16" barrel and subsequent slower velocity then a 1:8 will be necessary, or maybe Sierra is just being conservative and want the bullets to be stable at minimum book loads.
Last, when working 'near the edge' atmospheric conditions can change enough to upset the stability. Much colder or warmer, higher or lower elevation, humidity can all change the stability of the bullet. Some variations of the Miller equation (like JBM) allow input of temp and pressure due to this.
Thanks, I'll play around with that calculator to see what I can learn.
I loaded a few different powders and bullets this week.
This was 42 grains of RL-16 with 140 grain Barnes Match Burner bullets, loaded at seating depths of 2.260, 2.220 and 2.180 in two three shot groups. I was following the advice in the Berger manual for loading VLD bullets. The top left and middle right were loaded to 2.260. The top right and bottom left were loaded at 2.220. Finally, the middle left and bottom right were loaded to 2.180. The first group at 2.180 averaged 2658 FPS with an ES of 17 and SD of 7. The second group averaged 2659 with an ES of 29 and SD of 12. I don't think I've shot a bad group with this powder and bullet. I think I'm going with 2.180 since it will load in a magazine, but the others weren't that bad either.
I used this target for varying loads of H4350 with 140 grain Nosler RDF bullets with a seating depth of 2.298 which is at the lands. I really like that 41.4 grain group. That group averaged 2642 with an ES of 10 and SD of 4. The ES and SD numbers were much smaller with Hogdon 4350 than RL-16 or Winchester 760. Notice I don't have any measurement on the middle right target? I don't know where the third bullet went. I don't think its likely I missed the target entirely, but I can't say it went in one of the other holes either. I only shot two rounds at the bottom left target as I had a misfire with one.
This was Winchester 760 loaded with 140 grain Berger Target VLDs. I extrapolated data from the Hornady manual and Barnes website to come up with the min and max loads for this combo as the Berger data seemed to call for very low loads. The brass didn't show pressure signs at any of these loads. It's an interesting target as the initial impacts were much lower than those with RL-16 or H4350. I adjusted the scope up after the first three groups. I don't have good data for ES and SD because about every other shot failed to record on the chronograph. Velocity varied from just below 2600 to 2665 at the max load today.
So the top target were all the same except seating depth? And no scope change? So you should overlay each pair of groups to give you 6 round groups. Will give you a better idea of which seat depth is better.
When it boils down to the final 'settings' I shoot a minimum of a 5 round group. The only time I shoot less than 5 rounds is the initial velocity ladder (which is 3rnd each). There are enough data points that I can identify a trend (most of the time).
I only mention because I have had to redo a series. The 3 round groups looked wonderful. But, a 5 round series showed a different preference.
I'll start shooting five round groups now that I'm close. I just didn't want to waste the powder, primers and bullets on loads that weren't close.
Understand. For me it's the kind of thing that a 3rnd bad group will show a bad load, but, a good group may not be a good load.
And then there is the 'me' factor. Sometimes a bad group is just me not shooting well. I tend to get that a lot more than I'd like :)
For anyone interested, Graf and Son's had H4350 in 8 lb jugs today.
Very common consensus. Wait untill you take it out to 500 plus.I used this target for varying loads of H4350 with 140 grain Nosler RDF bullets with a seating depth of 2.298 which is at the lands. I really like that 41.4 grain group. That group averaged 2642 with an ES of 10 and SD of 4. The ES and SD numbers were much smaller with Hogdon 4350 than RL-16 or Winchester 760.
The Dunning-Kruger effect is alive and well.
I like this one
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