Interpeting Magnetospeed Data

[Tikkamike]

I didnt reqad all the replies so I dont know what has been said but here is what I think.. 1. your SD isnt that bad, I dont think your load is crap I think there are things you can do to make it better. first off your barrel was much dirtier by the end than it was when you started following the trend with that in mind tells you a lot. same with barrel heat.. I dont know what you temp there is but by the end of 2 hours that is only 8 minutes between shots. so maybe shoot less each day or stay longer.. what dies are you using? expander ball or bushing? what are your neck thickness measurements? did you anneal? because each piece of brass will work harden at a different rate especially if the neck thicknesses are different. what are you using to weigh each powder charge? same primers in every one? same lot of powder?... lots and lots of variables.. that being said your first 5 shots have an ES of 18.. Maybe you are expecting less but unless you are turning necks weight sorting brass etc you cant blame that ES on your load..even then im not sure I would. take your average (which we always do in this game) 9 fps variance one way or the other... you will never see that 9 fps on paper or in the field. I am all for striving for better.. lessen the variables and improve the margin for error always! but just tinker with your loading technique a little and see if you can change those numbers without changing your load. You stand to learn a lot with an experiment like that... one more thing.. dont do it once.. get your numbers then go verify and reverify them that way you know any changes are real results and not coincidence

 

[Bishop]

Worked a bit more on the load this weekend, ended up with these results. All testing done at 100 yards WITH the magnetospeed hanging offa my barrel, even for the groupings. These are CTC groups


Dropped my powder charge down to 43.5g imr-4064, used same seating depth etc, virgin lapua brass, WLR primers. I shot two 3 shot groups and one 4 shot group with each load. The 4 shot group had 1 flyer every stinkin time for cripes sake.

2786 avg fps ES-34 SD-11 for 10 shots Best 3 shot group .190 worst .526 1-flyer out by its lonesome

Load number 2 was 43g imr-4064, everything else just like previous.

2772 avg fps ES-33 SD- 9 for 10 shots Best 3 shot group .132 worst .702, again 1-flyer way out by its self.

Load number 3 was 42.5 imr-4064, everything else like previous

2743 avg fps ES- 18 SD-7 for 10 shots Best 3 shot group .255 worst .572, again a flyer out all by its self. Im beginning to see a pattern here.

I am thinking the group sizes are mostly due to my lack of consistency shooting from a bipod.

I think my next step will be to take load number 2,3, and a load at 42 grains even, and group them at 4 or 500 yards and see if i can see an actual difference. Because the group sizes of all of these loads fall well within the skill level of the shooter. I doubt I can actually Hold .5 moa consistently without screwing something up.

Why do the loads number 1, and 2 at 43.5g and 43g only exhibit a 10 fps difference avg for a half grain charge size? Is that some form of pattern or some sort of "node" that I should use as a reference point? Then the load number 3 at 42.5g loses 30 fps avg to the 43g load. Are the velocity numbers between 43g, and 43.5g indicating something I should pay attention to? 10 Fps for a whole half grain looks mighty nice to me! Should i just actually fine tune the load between 43.5 and 43?

Also, the flyer in every group was to the right every time. I am a right handed shooter, am i torqing the rifle possibly on some shots? Is this common for a right hander to throw shots to the right? And it was always on the last group i shot, the 4 shot grouping.

 

[Greyfox]

Worked a bit more on the load this weekend, ended up with these results. All testing done at 100 yards WITH the magnetospeed hanging offa my
.......2743 avg fps ES- 18 SD-7 for 10 shots Best 3 shot group .255 worst .572, again a flyer out all by its self. Im beginning to see a pattern here.

I am thinking the group sizes are mostly due to my lack of consistency shooting from a bipod.

I think my next step will be to take load number 2,3, and a load at 42 grains even, and group them at 4 or 500 yards and see if i can see an actual difference. Because the group sizes of all of these loads fall well within the skill level of the shooter. I doubt I can actually Hold .5 moa consistently without screwing something up.
Should i just actually fine tune the load between 43.5 and 43?

Also, the flyer in every group was to the right every time. I am a right handed shooter, am i torqing the rifle possibly on some shots? Is this common for a right hander to throw shots to the right? And it was always on the last group i shot, the 4 shot grouping.

I think that shooting consistent .25MOA groups or better off a bipod is a tall order without extensive practice and concentration. 42.5-43gr looks to be in the accuracy/ES node, and very consistent with results that I have gotten with the same recipe. I use 42.5gr. While you can certainly try optimizing in the 42.5-43gr weight range, I would generally change powder or primer given my brass prep was optimized if I wanted to tighten ES, but at this point you may want to test these loads at long range to see how they perform.

 

[Bishop]

If i could get components i would try different primers, i have 20 lb of imr-4064 since that was all i could get so changing powder isnt an option at this point, i am steadily buying up varget here and there and reloder 17 is available sometimes. When i get enough saved up i may switch. i may see what i can get some 175 bergers to do, or some 178 amax. This chamber has a .3442 neck, so i dont think i would gain much by neck turning, the lapua seems to be pretty good. I have i think .003 clearance with the lapua brass at .015 neck thickness, i think a loaded round measures .338 and i size with a .336 bushing for 1 thou of springback, leaving me with 1 thou of tension. I could turn and get a .334 or .335 bushing i guess. Dont know how much that would help with the .344 neck chamber though.

Seems that fed and cci primers are fairytale fodder for now, but wlr primers are growing on trees.

Im going to sort by ogive and see what that does for my ES and accuracy, then check it at 4 to 600 depending on the wind!

Ill report back in a week or two! Thanks!!

 

[liltank]

If i could get components i would try different primers, i have 20 lb of imr-4064 since that was all i could get so changing powder isnt an option at this point, i am steadily buying up varget here and there and reloder 17 is available sometimes. When i get enough saved up i may switch. i may see what i can get some 175 bergers to do, or some 178 amax. This chamber has a .3442 neck, so i dont think i would gain much by neck turning, the lapua seems to be pretty good. I have i think .003 clearance with the lapua brass at .015 neck thickness, i think a loaded round measures .338 and i size with a .336 bushing for 1 thou of springback, leaving me with 1 thou of tension. I could turn and get a .334 or .335 bushing i guess. Dont know how much that would help with the .344 neck chamber though.

Seems that fed and cci primers are fairytale fodder for now, but wlr primers are growing on trees.

Im going to sort by ogive and see what that does for my ES and accuracy, then check it at 4 to 600 depending on the wind!

Ill report back in a week or two! Thanks!!

I would say to start changing your seating depth. That may help with your flier. I know your limited on components, so that would be my next move. The only other thing to do is try different bullets like you want to, or start using some of the Varget you have accumulated. Primer would be my move. But as you said, your limited. Try those other things first. I forget if it was suggested yet, but maybe have the crown. Heckled for a small burr, or see if the throat may have a burr or something. Just a thought. Won't tell ya how my range session went today. You'll hate me!

 

[Bishop]

I would say to start changing your seating depth. That may help with your flier. I know your limited on components, so that would be my next move. The only other thing to do is try different bullets like you want to, or start using some of the Varget you have accumulated. Primer would be my move. But as you said, your limited. Try those other things first. I forget if it was suggested yet, but maybe have the crown. Heckled for a small burr, or see if the throat may have a burr or something. Just a thought. Won't tell ya how my range session went today. You'll hate me!

Gimme a range report anyway, i may hate you for it but ill thank you later lols.

 

[liltank]

Gimme a range report anyway, i may hate you for it but ill thank you later lols.

I loaded up my usual way to find loads for my rifles.

The first is my Savage LRPV in 22-250. I want to change over to 64grn Bergers when I run out of 53grn V-max. I have some 60grn V-max that were given to me. So to see how well my rifle would handle them, I loaded 6 different powders. The one that stood out the best was RL19 w/ an ES of 3 and an SD of 1 w/ an avg of 3578fps. The group was about 3/8" at 100. This is with a 3 shot group. I had other powders that provided a higher velocity, but the SD wasn't there. The second best is H380 at 3703fps with an SD of 11. That's not bad for all the further I'm shooting with the 22-250, but I'd rather have the smaller ES and SD.

The second was my stand by load for my Semi-custom Savage. It's with a 175 Nosler CC. 44.5grn of RL15 at 2690avg. It has an SD of 2. ES is some where around 7fps. This load shoots consistently in the low .2's for 3 shot groups.

I wanted to try some Berger 168 Hybrids through it. So far with the RL15, I found a load at 45.5grn at 2736avg w/ an SD of 4. Second best is 44grn at 2617avg w/ an SD of 9. This second group was the best, but the first was probably in the .345" range. The Lothar barrel I use is an outstanding shooter.

I just threw some loads together for my hunting rifle with H4831. Not sure what the velocity was, but using 208 A-max and 46grns of H4831 produced a 3 shot group overlapping one another horizontally. It is a factory Remington in 300SAUM. The only thing I did was do some trigger adjustment and put a clamp on break to the mountain barrel. Thing kicks like a mule w/o the break.

The one thing that I do consistently is set the bullets .014-.015 of the rifling every time I try to find a load with any bullet. I can always find a load within 2.5grns of powder stepping it up in half grain increments. So that is five different loads for one bullet. The only time I set them deeper is if I am trying to achieve magazine length.

Rifle: Savage Mod12 VLP action and stock, Tuned bolt, 28" Lothar Barrel 1:12
168 Hybrid, RL15, BR2 primer, RWS Brass set at 2.290" (this is set to magazine length)

44- 2617avg SD 9
44.5- 2664avg SD 15
45- 2694avg SD 14
45.5- 2736avg SD 4
46- 2762avg SD14

Just to give you an idea of how I do things. Only one group went over a .5" The one thing I did notice is that I room to add powder. 46grns gave a little show of primer flattening, but not enough to be alarmed yet. I have a feeling I can go another .5 to 1.5 grains. The only problem is that I will probably start to see diminishing returns at that point. In the summer it could be an issue. I believe the 45.5 is a good start until I can get the other loads tested.

Jeromy

 

[Bishop]

The 3 shot group on paper measured .396 ish outside diameter. Comes out to .088 CtC. I'll call it 1/10th I reckon.

The 5-shot group on the steel is at 600 yd, didnt measure it but that steel plate is supposed to be 10 inches diameter. Wind bit me on the one to the left, looks like I am seeing a bit more vertical than I want. It is most likely due to my shooting form and aiming point though. I was just trying to center my aim in the plate, nothing really small to focus on, gonna have to get some dots on those plates!

This load was 43g IMR-4064 175 SMK length sorted by ogive comparator *but not weight sorted* once fired lapua brass, F/L sized with a .336 bushing die, .005 jump, out of my Longrangerifles llc .308 win. avg velocity 2773 the S/D was 9 for the 5 shots I chrono'd with the magnetospeed before I took it off to shoot the group, the ES was like 20 or less I cant remember for sure. The magnetospeed does affect accuracy when it is hanging off of my barrel. However it still wants to shoot mostly 1/2 in groups with it. The load chrono's at 2773 avg fps.

Winds were gusting from 0 to 10mph today, made it interesting to shoot. The wind makes a HUGE jump in how it affects the .308 bullet from 4/500 to 600 yards it seems. When the winds are pretty constant, its easy, but when the wind dies from 10 mph to 1.5 mph, and then gusts back up to 10 mph, or vice versa, as you start pulling the trigger, it makes it quite interesting!

Reasonably happy with the load, wish I could try some different primers though. I have enough IMR-4064 to load roughly 3k rounds though, so I will be shooting this stuff for a while i think.

I'm pondering doing a very light neck turn on the brass to uniform the neck tension as much as I can just to see if I can squeeze some lower S-D out of it. The annealing machine is going to have to wait till next year though sadly.

 

[liltank]

The 3 shot group on paper measured .396 ish outside diameter. Comes out to .088 CtC. I'll call it 1/10th I reckon.

The 5-shot group on the steel is at 600 yd, didnt measure it but that steel plate is supposed to be 10 inches diameter. Wind bit me on the one to the left, looks like I am seeing a bit more vertical than I want. It is most likely due to my shooting form and aiming point though. I was just trying to center my aim in the plate, nothing really small to focus on, gonna have to get some dots on those plates!

This load was 43g IMR-4064 175 SMK length sorted by ogive comparator *but not weight sorted* once fired lapua brass, F/L sized with a .336 bushing die, .005 jump, out of my Longrangerifles llc .308 win. avg velocity 2773 the S/D was 9 for the 5 shots I chrono'd with the magnetospeed before I took it off to shoot the group, the ES was like 20 or less I cant remember for sure. The magnetospeed does affect accuracy when it is hanging off of my barrel. However it still wants to shoot mostly 1/2 in groups with it. The load chrono's at 2773 avg fps.

Winds were gusting from 0 to 10mph today, made it interesting to shoot. The wind makes a HUGE jump in how it affects the .308 bullet from 4/500 to 600 yards it seems. When the winds are pretty constant, its easy, but when the wind dies from 10 mph to 1.5 mph, and then gusts back up to 10 mph, or vice versa, as you start pulling the trigger, it makes it quite interesting!

Reasonably happy with the load, wish I could try some different primers though. I have enough IMR-4064 to load roughly 3k rounds though, so I will be shooting this stuff for a while i think.

I'm pondering doing a very light neck turn on the brass to uniform the neck tension as much as I can just to see if I can squeeze some lower S-D out of it. The annealing machine is going to have to wait till next year though sadly.

I wouldn't mess with the load or brass quite yet. Stretch it out farther and see what it does. Sounds like your SD is where it needs to be. Or as close as you can get it. Single numbers are good. Tighten up your shooting procedures and techniques. You will see marked improvement. That group doesn't look too bad. That's all you can do right now as you are limited in components. Keep shooting!

 

[Bishop]

Thanks! I'm going to try it out a bit farther as soon as i can.

Found some cci #200 primers in a LGS they want $50 per 1000. Im not that desperate yet. I can order them and pay haz-mat and SAVE money if i order at least 2k. If only they were in stock somewhere.

 

[liltank]

The 3 shot group on paper measured .396 ish outside diameter. Comes out to .088 CtC. I'll call it 1/10th I reckon.

The 5-shot group on the steel is at 600 yd, didnt measure it but that steel plate is supposed to be 10 inches diameter. Wind bit me on the one to the left, looks like I am seeing a bit more vertical than I want. It is most likely due to my shooting form and aiming point though. I was just trying to center my aim in the plate, nothing really small to focus on, gonna have to get some dots on those plates!

This load was 43g IMR-4064 175 SMK length sorted by ogive comparator *but not weight sorted* once fired lapua brass, F/L sized with a .336 bushing die, .005 jump, out of my Longrangerifles llc .308 win. avg velocity 2773 the S/D was 9 for the 5 shots I chrono'd with the magnetospeed before I took it off to shoot the group, the ES was like 20 or less I cant remember for sure. The magnetospeed does affect accuracy when it is hanging off of my barrel. However it still wants to shoot mostly 1/2 in groups with it. The load chrono's at 2773 avg fps.

Winds were gusting from 0 to 10mph today, made it interesting to shoot. The wind makes a HUGE jump in how it affects the .308 bullet from 4/500 to 600 yards it seems. When the winds are pretty constant, its easy, but when the wind dies from 10 mph to 1.5 mph, and then gusts back up to 10 mph, or vice versa, as you start pulling the trigger, it makes it quite interesting!

Reasonably happy with the load, wish I could try some different primers though. I have enough IMR-4064 to load roughly 3k rounds though, so I will be shooting this stuff for a while i think.

I'm pondering doing a very light neck turn on the brass to uniform the neck tension as much as I can just to see if I can squeeze some lower S-D out of it. The annealing machine is going to have to wait till next year though sadly.

Yep, know what you mean. I shoot the match primers. They can't be found anywhere.