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bjornborud
Tonight I hit the range in full stride with two new gadgets in addition to my XCB rifle: A new in the box MagnetoSpeed V3, and an equally new Breech seater from Tim Malcolm aka Goodsteel.
Just to cover the MagnetoSpeed chronograph very simply: It works perfect with cast bullets, is very simple to install and use, and appears to be very accurate when I compare today’s loads with those previously shot and chronographed. After shooting I took the little SD card out of the display unit, hooked it up to the computer, clicked on the log file and Voila! it opened up the entire range session in Excel. Now I can tape the data on the targets along with the groups for more clarity.
The Breech Seater was a very interesting contraption, and from my limited use of it today I am starting to believe that breech seating helps accuracy at high velocity.
All shooting tonight was done with The NOE 310-165-FN bullet, lubed with White Label 2700+ (Carnauba Red)
First off I shot 2 strings with fixed ammo to confirm the velocities I posted in my previous post. I estimated that a load of 45 grs. W760 would give about 2550 fps, and tonight’s shooting showed the following chrono results:
Both ES and SD were within reasonable limits.
Then I shot a string with LeveRevolution. That’s when things started to heat up, velocity wise:
Very good velocities, spreads were a little more uneven. I’ll be trying to push this powder even higher to see if it’ll break 3000 fps with accuracy.
Breech seated reduced loads didn’t seem to have a large advantage over fixed ammo loads. I shot 2 strings with 13 grs. Unique, accuracy was about the same:
The most interesting experiment of the evening came when I attempted to shoot 5 cases pre-loaded with 56 grains RL22. This charge fills the case to overflow, so I have to put a “lube cookie” in the case mouth to be able to load the case:
Breech seating the bullet:
And the result was pretty decent:
All in all a very interesting night at the range, I’ll post more when I have more data to share.
bjornborud-
Replies
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frankelliott
It may be easier to get accuracy with BSed, PB slower bullets, I don’t know as we can’t use GC’s in our shooting.
200 Yards, Benchrest
200 yards Benchrest 5 shot group.
.367” Jeff Schultz 2007Benchrest, 25 shots in 5 groups, single entry, annual match (summer)
1.091” Dale Reynolds 2010Rowland Match: Benchrest, 10 shots for group, single entry, annual match (spring)
1.240” Jeff Schultz 201110 Shot Group Match: Benchrest, single entry, annual match (fall)
.924” Dale Reynolds 2011There are two 10 shot 200 yard records (don’t know why) for 200 yards. With our slower bullets 200 yards is not easy.
Over the year, we don’t shoot many matches at 100 yards
100 Yards, Benchrest
Kelly Match: 5 shots for group
.141” Andy Zahornacky 2011Bartlet Match: (5) 5 shot groups for average
0.3882 John Louis 2014More common match results will be 1.5-1.75 times these records.
That gives you something to “shoot for”, pun intended
It should be possible with less wind drift at much higher velocity. I’m sure you can get there one step at a time.Frank
ianharris
What do I always call it? “Imagine getting more”, I think it was a cigarette slogan from years ago. I used to do a lot of imagining and finally figured out some ways to get better results, but it’s tough to nail down exactly what cause had what effect since each rifle seems to march to it’s own beat. Breaking it down into specific tests like these sure helps us figure out what’s going on, at least in specific instances.
There have been a lot of theories and opposing views over the years as to what exactly is happening, particularly regarding that first half inch of bullet travel. Many think that just engraving the nose and sizing the bands to throat diameter will eliminate any problems there, but we all know that isn’t enough to get good groups at HV. Still, without positive, comparative demonstrations, it’s impossible to make the case that launch damage is indeed the cause of HV accuracy deterioration and it leaves the door open for a lot of other speculations, disagreements, and theories. Some folks thought it just wasn’t possible to get accuracy beyond a certain point because it wasn’t practical to cast a balanced-enough bullet, but the paper-patchers years ago and now the breech-seaters proven that isn’t necessarily so. Some people think it’s too much muzzle pressure, but lots of people including myself have shot slow powders out of short barrels and found that muzzle pressure, in and of itself, is no more of a factor than spin rate is IF the bullet isn’t out of balance and the base is true. Still others, myself included, think there is something detrimental going on at high velocity with steep twists and the pressure-side of the lands, something that is mitigated by harder alloys, paper jackets, and/or slower than normal twist rates. The only test I’ve been able to devise for that is a high speed camera to capture a detailed image of the bullet in flight, such as you and I have discussed in the past.
Regardless, the first bit of travel through the throat is probably always going to be the biggest challenge to overcome with fixed ammunition, and we already know the result our methods need to achieve. I think you fellers got a pretty good start on showing one way to do it. I’m going to keep working on the other end, faster twists, softer bullets, sporting-weight rifles, etc., and see if I can’t contribute to the repertoire.
Gear
lar45
Wow, simply great results, and a very interesting thread!
I was hoping that this would work much better in a 14 twist rifle.
With Tim’s 10 twist, and 2300ish fps, we would get several right on top of each other and then get one that would jump out 4″ or so.
With a little practice I could get the bullets to seat smoothly in one stroke of the seating lever. I wonder if the fliers could have been caused by the boolits that didn’t seat as smoothly as the others?It looks like Carnauba Red(2700) does not work as well with the lower velocity loads.
timmalcolm
Gear, understanding what when how and why with a phenomenon we cannot see, observe, or measure except by shots on target is only possible if we each post our specific experiences. We have the answer. In fact, we probably have three answers, but the pieces of the puzzle are distributed amongst us. If only people would do what I have begged them to on many many occasions and simply contribute their piece of the puzzle, we might actually move the cast bullet community forward. Our fathers and grandfathers knew how to do this and they achieved great things without the help of the internet. I believe this can be a good thing if we quite arguing methods and semantics and simply work together.
I will invite you once again to join the discussion and bring your insight to the table. You are welcome here by EVERYONE if you will check the drama and history at the door and focus on the science.
This project is an great example of acceptable documentation that noone will ever have a problem with:
I postulated a theory
I constructed a test
I attempted to prove it and failed.
I sent the tools to a man who is as good at punching paper as I am at spinning dials
He used the tool and succeeded where I failed.
He posted a complete description with pictures and chronograph readings.
He will soon explore the use of these tools further and give a full report with pictures and chronograph readings.Bjorn posts the good the bad and the ugly, but he is perfectly transparent and candid with his posts so that we all can observe the data and possibly see something that he did not, or at the very least learn along with him.
In this way each posted group educates not just the shooter, but the entire forum so that we might all get where we are going.
If you would like to join in, and conduct yourself in this way, I think I speak for the entire membership when I say you are welcome here.
Please join in, and lets have a little give and take.Ian is not only welcome, he’s a natural here, having been involved in HV shooting just about as long as anybody else. This is no place for secrets (not that I think Gear is trying to hide anything), but other actors on the scene have intimated that there are “things” only they know about and that they are not willing to share. To them I only say: It looks like we are climbing these hurdles without your help, so thanks for nothing.
Here are my plans for the breech seater: Since a case filled to overflow with RL22 gave me about MOA at 2850 fps, I will repeat this load shooting a 10-shot group. If it holds up I’ll move on to faster powders (there were no pressure signals with the RL22), again shooting full cases. I want to see where the shotgun pattern starts. Or maybe where the rifle starts to lead. The lino bullets seem to work fine, but I also have WQ Lyman #2, and also some heat treated straight WW which is above BHN30 now, and some HT 87-12-1 which is still curing. I have no idea how these alloys will react to this kind of speed, but there’s only one way to find out. I’m sticking with 2700+ for lube, keeping an eye on that component also.
I agree with Gear that W760/H414 is a powder worth pursuing, especially since it is heavy for volume and can be increased up towards insanity (but good insanity).
Planning to shoot Sunday, posting will follow.sgt.mike
…………………. I think you fellers got a pretty good start on showing one way to do it. I’m going to keep working on the other end, faster twists, softer bullets, sporting-weight rifles, etc., and see if I can’t contribute to the repertoire.
Gear
Gear, I do look forward to your results probably more than you ever think.
Until the Brux barrel gets here I’m sort of in the same boat as you are in the 10 twist, sport / milsurp rifles arena But as soon as time frees up I’ll burn the powder in a couple of differant bullets and ease my way back up again.Now if ya’ll will excuse me I have to stop off by Walmart I hear they have a sale on bannanas
frankelliott
ianharris
lar45
timmalcolm
sgt.mike
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