7 RSAUM Load thread...Post your 7RSAUM(ony 7RSAUM) Load

[falconpilot]

Erik,

We gotta talk about this quick load thing!!! My quickload's isn't even close to what I actually see. Maybe you'll share your secerts

 

[sailhertoo]

I've looked for a thread on here that post 7 RSAUM loads only, and haven't found one, so lets start on here. Just got my chambered up and a little surprise at the velocities that I'm getting so, I needed some comparsions...

So far...

Bat with 31" Bartlein 1:87-1:93 twist, Remington Brass, Fed 210M's, .3195 neck with .200 freebore, Beger 180 Hybrids jumping .015, OAL 3.110...Temp 65F Barrel has 55 rounds through it..

VV560 - 61.0 - 2870fps
VV560 - 62.0 - 2955 fps
H4831SC - 61.0 - 2901 fps
H4350 - 56.0 - 2875fps

The VV560 groups were not good at all, while the H4350 fired a .741 actual size group at 300 yards(5-shots)....

I was expecting velocities quite a bit faster based on what everyone is saying...Several places in these forums were it's spoken about Biggs getting 2950-3000 with 56 grs of 4350...

Please post your loads...

I would tell you but then I would have to kill you.

All gun barrels are different, what works in mine will not work in yours most likely. Do your work up and put in the time... it will be worth it.

It takes alot of time to try to be at the top of the field..and then theres that peski wind, relay number, target number, home field advantage,...ect..etc...


But I digress....

I use H1000, 60.9 gr, with 180 hybrids.

+ or - 3000 fps. out of 31" barrel.

Apparently I have a hot lot of H1000 'cause most folks arn't getting these velocities.

 

[Erik Cortina]

I don't have a SAUM, I used QuickLOAD to figure out that his load was too light to be accurate.

Let me rephrase that.

I don't have a SAUM, I just know.

How's that? ;D

 

[Erik Cortina]

Second, how will QL predict a load running already close to the top is absolutely "too light to be accurate"? What if the load he was shooting was just 15 fps above the "low node"?

62.0 gr. N560 in not running close to the top.

QuickLOAD predicts that 62.0 gr. N560 is only running at 53,973 psi. in a cartridge capable of 65,000 psi. According to QuickLOAD, max load for N560 in a SAUM jumping the 180 Hybrids is about 3,100 fps. *** THIS MIGHT NOT BE SAFE IN SOME GUNS, SO APPROACH WITH CAUTION***

 

[Mark Walker in TX]

Second, how will QL predict a load running already close to the top is absolutely "too light to be accurate"? What if the load he was shooting was just 15 fps above the "low node"?

62.0 gr. N560 in not running close to the top.

QuickLOAD predicts that 62.0 gr. N560 is only running at 53,973 psi. in a cartridge capable of 65,000 psi. According to QuickLOAD, max load for N560 in a SAUM jumping the 180 Hybrids is about 3,100 fps. *** THIS MIGHT NOT BE SAFE IN SOME GUNS, SO APPROACH WITH CAUTION***

Let's continue:

So you say that QL predicts that max is 3100 fps, but it might not be safe. Then that is not a realistic number for our discussion. His load was already at 2950, so lets say then he is only 100 feet from realistic safe max of 3050. We can disagree, but I will still call 100 foot from the top, close to the top. It is 97% of the max.

How does QL predict that the load at 3050 will be more accurate than the load at 2950? Also, again, how does it predict that he is not just above a lower node, say at 2930 that gives great accuracy, in his particular rifle?

Does QL actually make accuracy predictions at all, or is this where the 'I don't have a SAUM, I just know" applies? Again, I don't have QL, I never used it, or even seen it, so I am really trying to determine its capabilities.

ETA: Really, I already know you are completely full of shit, that's a given from all the times we have shot together. Speaking of, are you coming over for the 1k on Sun? I'm just really interested if QL is capable of making such precise recommendations as I am going down the road of load dev again myself and this short barrel life of these magnums just scares the crap out of me. Always looking for the better mousetrap, as it were...

 

[Erik Cortina]

Second, how will QL predict a load running already close to the top is absolutely "too light to be accurate"? What if the load he was shooting was just 15 fps above the "low node"?

62.0 gr. N560 in not running close to the top.

QuickLOAD predicts that 62.0 gr. N560 is only running at 53,973 psi. in a cartridge capable of 65,000 psi. According to QuickLOAD, max load for N560 in a SAUM jumping the 180 Hybrids is about 3,100 fps. *** THIS MIGHT NOT BE SAFE IN SOME GUNS, SO APPROACH WITH CAUTION***

Let's continue:

So you say that QL predicts that max is 3100 fps, but it might not be safe. Then that is not a realistic number for our discussion. His load was already at 2950, so lets say then he is only 100 feet from realistic safe max of 3050. We can disagree, but I will still call 100 foot from the top, close to the top. It is 97% of the max.

How does QL predict that the load at 3050 will be more accurate than the load at 2950? Also, again, how does it predict that he is not just above a lower node, say at 2930 that gives great accuracy, in his particular rifle?

Does QL actually make accuracy predictions at all, or is this where the 'I don't have a SAUM, I just know" applies? Again, I don't have QL, I never used it, or even seen it, so I am really trying to determine its capabilities.

ETA: Really, I already know you are completely full of shit, that's a given from all the times we have shot together. Speaking of, are you coming over for the 1k on Sun? I'm just really interested if QL is capable of making such precise recommendations as I am going down the road of load dev again myself and this short barrel life of these magnums just scares the crap out of me. Always looking for the better mousetrap, as it were...

Well Mark, I'm not full of shit as you so vulgarly put it. And Jim's results prove it!

And to answer your question, yes, QL can tell you when you are above or below an accuracy node. He was in between, but since I already know he wants to be between 2,950 and 3,050 fps. I was not going to suggest that he drop the powder charge. And since there are unknown variables to me such as H2O overflow capacity, exact barrel length, etc. I simply informed Jim that he was too light and advised him to work up. So he did as I advised and the result was better accuracy!

As far as shooting Sunday I'm not sure since I might go hunting.

 

[Mark Walker in TX]

Well Mark, I'm not full of shit as you so vulgarly put it. And Jim's results prove it!

And to answer your question, yes, QL can tell you when you are above or below an accuracy node. He was in between, but since I already know he wants to be between 2,950 and 3,050 fps. I was not going to suggest that he drop the powder charge. And since there are unknown variables to me such as H2O overflow capacity, exact barrel length, etc. I simply informed Jim that he was too light and advised him to work up. So he did as I advised and the result was better accuracy!

As far as shooting Sunday I'm not sure since I might go hunting.

Ahh, you're still full of shit. Obviously if a load is not shooting, you have to tweak it and see what happens, maybe it works, maybe not. Looks like for Jimbo the 4350 is shooting about 1/2 the vertical of the 560, so it's a moot point anyway. Enough on that...

Please elaborate on specifically how does, just like you state with the unknown variables, QL predict where the nodes are within such a small range? What does it tell you, or what are you looking at, specifically? That is interesting to me given my interest in developing my own case designs, yet keeping barrel wear to a minimum - these things are getting expensive. I'd just as soon pay for computer simulations vs. barrels, bullets, powder, time, if it really is that accurate of a predictor. Jim claims above it isn't and what he sees is way off from reality, so you seem to be in disagreement on this issue.

 

[Steve Blair]

Mark,

I use the same approach that Erik does with QL and will add what meager knowledge I've gained.

QuickLOAD can tell you the approximate barrel time for a given load. Barrel time for a given length is important when credence is given to Chris Long's OBT Theory.

http://www.the-long-family.com/OBT_paper.htm

I started noticing some time after I bought QuickLOAD that all my best loads were falling very near or on a barrel time node as Chris defines it. I have attached a text file with all of the nodes from 16 to 36 inch barrels. The program becomes really useful when powder Burning Rate Factor (Ba), Shot Start Pressure and Maximum Case Capacity are adjusted to mirror real data recorded with a specific rifle and load.

The program can also show when pressure is near full working pressure. This is affected by the Ba adjustment and using actual case capacity (H2O) measurements. My experience is that loads produce minimum velocity variation when near full pressure. The Ba adjustment is not linear, so caution and traditional development methods are still relevant. QL has no means, for instance, to account for primer differences.

It is not a perfect tool but has enabled me to find good loads much faster than previously. For me, definitely worth the price in saved components.

 

[Mark Walker in TX]

Awesome info Steve, thanks a bunch. That is exactly what I have been wanting to know about the program!!

 

[Steve Blair]

There was also a good article about using QuickLOAD as a predictive tool on this web site.

http://www.accurateshooter.com/gear-reviews/test-quickload-review/

 

[Erik Cortina]

There you have it Mark, quickLOAD will pinpoint a node based on barrel time, so that you can make the bullet exit the barrel when the barrel is changing directions. When the barrel changes directions, it stops moving for a small amount of time, and that is when you want your bullet to exit.

Read Steve's link and understand it, and then get QuickLOAD and it will allow you to find an accurate load faster because you will know how fast it needs to be going to be as accurate as it can be.

You will also be able to find out what barrel length works the best for a certain cartridge/powder/bullet combo. You will also know if you are wasting your time with a certain powder before you ever start testing that powder.

 

[JohnMill]

I am not so sure of your assessment of when the bullet should exit the bore. I will read more . Initially it seemed to me what Techshooter was saying was that the bullet shoud exit when the wave was effecting the diameter of the bore the least. I think there is a mixing of theories here and that the harmonics demonstrated on Varmint Als website are distinctly different from the OTB theory of Chris Long (acoustic shock wave).
That should stir this pot for a little while

All B Bock

John

 

[Steve Blair]

The nodes Chris Long identified represent the point when the shock wave is farthest from the muzzle, i.e.: at the breech. Chris' theory is that bore diameter is affected by the firing pulse and bullet exit should be timed to minimize the effect. Whether that is correct or not, something is happening that is associated with the nodes.

Barrel harmonics are also relevant. The thinner and more flexible the barrel, the lower the resonant frequency and greater the amplitude of harmonic vibration. Heavy, rigid barrels attempt to minimize this effect by increasing the resonant frequency and reducing the vibration amplitude. A good example would be the ~22" HV profile barrels typically found on short range BR guns. F-Class shooters also need velocity, so there is a trade between rigidity and length. Even a Ø1.25" barrel like the one on my F-O rifle exhibits this property. As length increases at a constant diameter, rigidity decreases. It seems that heavy barrels are less affected by vibration harmonics than what is occurring on the barrel time nodes.

We must also factor combustion characteristics as a contributor when shooting long range. As we all know, if the rifle is shooting one hole at 100 yards with an ES of 150, it will not be much good at 1000. This a classic multivariate problem and can reasonably be solved by iteration. Using software to model much of the iteration reduces component usage and saves barrels. As valuable as that is, there is still only one way to validate a given combination in a specific rifle.

 

[Mark Walker in TX]

Really, thanks for the info guys!! While it looks like there is lots of room for interpretation, and also you have to consider all of those unknown variables, it looks like there is probably more merit to the QL program that I had given it before.

I do still agree with Steve's last sentence "As valuable as that is, there is still only one way to validate a given combination in a specific rifle."

Jim, I am sorry for the complete hijack of your SAUM load thread. Really interesting stuff, though. My first barrel will be back from Rich tomorrow, and I'll let you know what I find...

Erik, weather is looking crappy for the Sun match, winter storm (at least for So. Texas) looks to be arriving Sunday and with the rain (1-2 inches) and 30+ mph winds expected, there is a good chance we'll cancel the match. As you know, our target frames just can't take that punishment. Ben or Glen will send out an email Sat night as usual - assume you are on the dist list..

 

[Erik Cortina]

Really, thanks for the info guys!! While it looks like there is lots of room for interpretation, and also you have to consider all of those unknown variables, it looks like there is probably more merit to the QL program that I had given it before.

I do still agree with Steve's last sentence "As valuable as that is, there is still only one way to validate a given combination in a specific rifle."

Jim, I am sorry for the complete hijack of your SAUM load thread. Really interesting stuff, though. My first barrel will be back from Rich tomorrow, and I'll let you know what I find...

Erik, weather is looking crappy for the Sun match, winter storm (at least for So. Texas) looks to be arriving Sunday and with the rain (1-2 inches) and 30+ mph winds expected, there is a good chance we'll cancel the match. As you know, our target frames just can't take that punishment. Ben or Glen will send out an email Sat night as usual - assume you are on the dist list..

Steve is right of course, you still have to get out and test the rifle, howerver, it will help you zero in on a good load faster.

Looks like my weekend is shot, turns out I'm not going hunting after all and I was hoping to shoot the practice match Saturday and then shoot Sunday again. Oh well, we need the rain, so let it rain!

 

[DBLTAPN]

H4350 59 gr 162 AMAX 3150FPS
H4350 56 gr 180 VDL 2950FPS

30" TUBE NOSLER CASES 300 SAUM RE-NECK

GREAT BALLISTICS/CARTRIGE VERY EASY TO TUNE

 

[ChosenFrozen]

I'm shooting a Barnard P with a 30" Bartlien 1:8 twist. Built by Warner Tool. It's a 7mm/300 RSAUM, which only means I have to trim the necks on a 7mm case. Neck turned Rem brass. .020" jammed 180gr. Mollyed VLDs. Federal magnum primers.
I shoot 62gr H4831sc and get 3035-3045fps out of it. Primer pockets have loosened up after 4 firings.
I throttled it back to 60gr. and get 2960fps and no pressure signs on the cases yet. As far as accuracy, I haven't found any difference between the two loads, just a few clicks of elevation at 800yds.

 

[kennyg]

I mentioned something about this on another thread, but I was just wondering how you guys decide whether to go with a magnum primer or standard?

I also have a 7 SAUM nearing completion (just put a coat of finish on the stock tonight It seems like this powder capacity is kind of on the edge as far as standard primers go? I plan on starting with H1000. Which primer should I try first?

Thanks for helping out a newbie.

Kenny

 

[trailrider121]

Have to bring this post back alive. Anyone using 168 vld's and H4350. I'll be building one in October and plan to use as a hunting / long range rig, will be using 24" barrel. Any good advice to point me in the right direction, I have lots of powder on hand.

 

[JohnMill]

Hell yeah bring it back. I got the hots to build one of these. The only thing stopping me is the fact that I have two that just came on line that I have not wrung out yet. this one and the .280Ackley are calling to me.

John