Finding a node: accuracy vs. velocity

[shguns]

I tried to use land riding FPB bullets with Blackhorn powder and was getting failure to ignite. But I found success with a 1/8" wool wad between the bullets and powder. It definitely did provide the seal I needed in my Disc extreme. 50 rifle.

 

[Sideshow]

I have never had a slow fire, hang fire, or failure to fire, in any of my guns shooting BH209. I’ve never chrono’d any of them either, so I have no idea the velocity or ES. I would guess the velocity is quite low compared to the stated velocity in the charts.

I can see where what you are saying might be and probably is true though.

I used a ballistic calculator, and went off the printed velocity for BH209 using the 100 grains volume and a 300 grain bullet (Parker BE’s) I don’t remember if it listed that bullet exactly or if I averaged all the 300 grain bullet speeds listed at 100 gns volume to get the velocity I punched into the calculator.

At any rate, my 400 yard shot I tried at a gong, missed by 5 feet low. So I feel there is definitely some credibility to your statement!. This was out of my bolt, Breech plug modded Austin Halleck .45.

At 100 yards, In a 15 mph crosswind, the group center was the size of a beer cap, however big that is.

The bullets are a bit snug to start, but then push right down. I may and probably do, need a tighter fit.....

Stacy youre a smart guy youll get this all worked out to your likeing im sure of that !!! 400 yds is a darn good poke !!! Does it correspond close to what you figured ?? Ive used a small duplex(3 or 4f) with bh209 also to accelerate the pressure curve a bit also with some bullets . Worked good for me . I got faith in ya , youll get this !!!
Maybe we'll just sit on down and make more of those "caps" available ....

 

[sdporter]

Stacy youre a smart guy youll get this all worked out to your likeing im sure of that !!! 400 yds is a darn good poke !!! Does it correspond close to what you figured ?? Ive used a small duplex(3 or 4f) too to accelerate the pressure curve a bit also with some bullets . Worked good for me . I got faith in ya , youll get this !!!

If I figured the MOA in the scope correctly, it was off a mile. Next couple of hundred I get that’s not needed, lol, gonna buy a chrono and see what they do. I can have my buddy come and shoot and borrow his for free, but I need to get my own.
My trips to the range are usually: I have a couple of hours with nothing to do, so load up and go, so he isn’t always available.
Next time I shoot that rifle, I’ll note the loading pressure, but if I remember correctly, it wasn’t much and the bullet started with my thumb. I’m sure it needs to be tighter....

 

[Sideshow]

If I figured the MOA in the scope correctly, it was off a mile. Next couple of hundred I get that’s not needed, lol, gonna buy a chrono and see what they do. I can have my buddy come and shoot and borrow his for free, but I need to get my own.
My trips to the range are usually: I have a couple of hours with nothing to do, so load up and go, so he isn’t always available.
Next time I shoot that rifle, I’ll note the loading pressure, but if I remember correctly, it wasn’t much and the bullet started with my thumb. I’m sure it needs to be tighter....

You got a knurler for your lathe use it and a file like Michiganmuzzy showed awhile back on the benchtop and see if it helps your fit . Seems like i knurl everything from conical , to especially solid coppers in sabots , darn near everything . Its my buddy !!! The posted bc could be fantasy numbers too . Many lie about that . I just picked up another chrono after my last one croaked for $25 . Fella bought a new Magnetospeed that hangs on the barrel for Big money . Right place right time i guess , i got very lucky . 45-70 just got a Dandy lab radar . Keep your eyes peeled ya never know.....

 

[ronlaughlin]

I used a ballistic calculator, and went off the printed velocity for BH209 using the 100 grains volume and a 300 grain bullet (Parker BE’s) I don’t remember if it listed that bullet exactly or if I averaged all the 300 grain bullet speeds listed at 100 gns volume to get the velocity I punched into the calculator.

At any rate, my 400 yard shot I tried at a gong, missed by 5 feet low.

One thing to consider is the ballistic coefficient listed on Parker website is for mv of 2850. You are no where near that, and the actual BC will be a way less.

 

[ENCORE50A]

I've got pre-weighed tubes from 63.0 to 84.0 in 3.5gr increments. I'm gonna go shoot them over my chrono (while also shooting groups) to see what I get. I'm a nerd (aka engineer) so I love to experiment and don't mind burning extra powder to collect extra data. If I can find a velocity & accuracy node to explore with this increment, I'll be pretty happy.

Your thread about the 2gr difference between 84 and 86 is impressive! That's the kind of consistency I'm after. Did you happen to capture the velocities of either of those loads? Since vertical stringing is indicative of velocity deviations, I'd be curious as to the magnitude of ES for those two loads.

Sorry, but I was only shooting the bullets for accuracy with production rifle charges. I won't use the chronograph until I start shooting long range.

 

[45-70]

Utah i think youre gonna find that you wont build sufficent pressure for Reliable ignition with wool wads . Youre gonna need veggie wads or polywads in order to get that bh209 lit off Reliably . Bh209 requires a good sealing wad in order to work like it should . Good powder but theres a few requirements its got and ya gotta meet them . Its also gonna appreciate a good crush seal on its full strength 209 primers , its actually about a little bit more than blowback but also a good burn of the powder and the hotter the better so its a federal 209a for me . I believe i get the best burn with the powder packed really tight as well . I use a Precision Packer to seat my load consistantly and it seems to help accuracy for me . Seal er up , pack er down and youll rock a critters world !!! If your a cf loader you know the benefits of fine stepped load development when your getting close . There really isnt any difference here . Take all the time you need ......

National Champion uses Wool wads

 

[45-70]

One thing to consider is the ballistic coefficient listed on Parker website is for mv of 2850. You are no where near that, and the actual BC will be a way less.

Won,t work without right BC

 

[ronlaughlin]

............Having shot BH209 since it became available, I've had no inconsistencies with it.........

Me neither. ES are low when ever they are checked. Have been since 2008. It is mystifying how "false truths" about Blackhorn persist. So much ignorance........

Just the other day the Fury 265g STB with a load of 95g Blackhorn was timed. Was so consistent, shooting was discontinued after only three shots. 1912 fps, 1924 fps, and 1915 fps.

So many myths, so many myths......... All because CVA breech plugs weren't reliable igniting Blackhorn.

 

[45-70]

Me neither. ES are low when ever they are checked. Have been since 2008. It is mystifying how "false truths" about Blackhorn persist. So much ignorance........

Just the other day the Fury 265g STB with a load of 95g Blackhorn was timed. Was so consistent, shooting was discontinued after only three shots. 1912 fps, 1924 fps, and 1915 fps.

So many myths, so many myths......... All because CVA breech plugs weren't reliable igniting Blackhorn.

I must be doing something wrong because deviation is sometimes larger than should be. I think that is why people say that. I myself compare to black powder because that can be in single digits

 

[Sideshow]

Guys i use wool at times too . Other times fiber or maybe polywads .

 

[UtahJimmy]

Well, I'm back from shooting. Gun is already clean and I've got a grin that's gonna be hard to wipe off. Super happy with my first session. 77gr seems to be a happy spot. 7fps ES with 3 shots and the group is well under MOA. I'll get some data up sometime this week, but overall very pleased.

No ignition problems to speak of. I believe I have some issues with blowby on the primer though. I'll share some photos of the soot that accumulated on my bolt as well as the amount on each primer to see if this is common or an area of concern.

Thanks for all the input so far.

I am still curious as to everyone's method for finding a node...

 

[45-70]

IMO i did have to Bob . Tech has EVERYTHING to do with it .
To your credit to did say black is a more stabilized es tho . Anyone care to correct that from him ?? Wouldnt be true but......

no I never said that. Black can get down in single digit and I don't care whether you believe or not it is true, that isfrom shot to shot. Kind of what PO is kooking for

 

[Sideshow]

Well, I'm back from shooting. Gun is already clean and I've got a grin that's gonna be hard to wipe off. Super happy with my first session. 77gr seems to be a happy spot. 7fps ES with 3 shots and the group is well under MOA. I'll get some data up sometime this week, but overall very pleased.

No ignition problems to speak of. I believe I have some issues with blowby on the primer though. I'll share some photos of the soot that accumulated on my bolt as well as the amount on each primer to see if this is common or an area of concern.

Thanks for all the input so far.

I am still curious as to everyone's method for finding a node...

Glad you had a good day . Velocity @ minimum es and accuracy nodes are generally 1 in the same . You could find a few if youd like .

 

[MSalyards]

I too shoot 77 w gr of blackhorn but with a 300 gr Deep Curl in a crush rib Harvester sabot. I also have the blow by stuck primer problem. I've tried the washer thing and measured primers. They still stuck. 2 different breech plugs, Nada! I'm going to try the Lehigh plug next as I have read some good reports. But for now I carry my primer removal tool.

 

[ronlaughlin]

I must be doing something wrong because deviation is sometimes larger than should be. I think that is why people say that. I myself compare to black powder because that can be in single digits

Neglected to share that the Standard Deviation of the timing was 6.

 

[ENCORE50A]

Well, I'm back from shooting. Gun is already clean and I've got a grin that's gonna be hard to wipe off. Super happy with my first session. 77gr seems to be a happy spot. 7fps ES with 3 shots and the group is well under MOA. I'll get some data up sometime this week, but overall very pleased.

No ignition problems to speak of. I believe I have some issues with blowby on the primer though. I'll share some photos of the soot that accumulated on my bolt as well as the amount on each primer to see if this is common or an area of concern.

Thanks for all the input so far.

I am still curious as to everyone's method for finding a node...

Curious...………. Did you use the components you mentioned in your first post?

I have yet to confirm this testing in my rifle, but one of the builders that shoots very heavy charges of BH in CUSTOM RIFLES, states that with BH, you can actually find more than a single node.
Because this is done with custom built rifles capable of much heavier charges than production rifles are capable of, I won't share his specific information. Don't ask.
He indicates that on "average", not absolute, that different nodes can be found in 10 to 15grs changes in the charges of BH. He builds, tests and develops load data for his custom rifles, so I trust his information. Your opinion may differ....

 

[sdporter]

I too shoot 77 w gr of blackhorn but with a 300 gr Deep Curl in a crush rib Harvester sabot. I also have the blow by stuck primer problem. I've tried the washer thing and measured primers. They still stuck. 2 different breech plugs, Nada! I'm going to try the Lehigh plug next as I have read some good reports. But for now I carry my primer removal tool.

What rifle? I’ve had them get stuck in my new CVA V2LR a few times. Fed 209a. I haven’t messed with primer crush and all that yet on that gun. I’ve shot it about 60-80 times. Maybe 100, I have yet to get a group under 1-1/2”. I don’t think I’ve weighed charges with that gun. I do with my Austin and Halleck. Those are the only two rifles I’ve shot BH209 out of.

 

[MSalyards]

CVA Accura V2 50 cal. I carry the primer removal tool around my neck on a lanyard with my starter. Just part of life and it will always be there even if I figure this problem out. Hopefully the Lehigh plug solves this problem.

 

[UtahJimmy]

Curious...………. Did you use the components you mentioned in your first post?

I have yet to confirm this testing in my rifle, but one of the builders that shoots very heavy charges of BH in CUSTOM RIFLES, states that with BH, you can actually find more than a single node.
Because this is done with custom built rifles capable of much heavier charges than production rifles are capable of, I won't share his specific information. Don't ask.
He indicates that on "average", not absolute, that different nodes can be found in 10 to 15grs changes in the charges of BH. He builds, tests and develops load data for his custom rifles, so I trust his information. Your opinion may differ....

I did use all the components in my original post. I would agree that I probably found 2 nodes. I didn't shoot either of the top two loads (80.5 & 84) because it started snowing and the wind picked up. 66.5 & 73.5 both had vertical stringing with larger velocity deviations, 70 & 77 had small ES and touching shots. I'll be exploring both those areas in addition to shooting the higher charges next time I'm out.