Vertical Stringing in a 45-70

[Dr. A]

I was very anxious last night to try out a load I had worked up a couple of weeks ago. Its in my 95 Marlin 45-70 that slugs at .458 and has been firelapped. I got one hole accuracy a couple of weeks ago with 42gr. of H4198 (1980fps), and a heat treated 300gr. RCBS gas checked .460 bullet. The previous testing was done at 50 yards, and I moved to 100. The original test was done with water quenched, with last nights being heat treated. I use tumble alox, and wondered if my application was not adequate. No star on the end of my barrel. Best group last night was 4 inches, with 5 being the norm. Horizontal spread was usually 1 to 1.5 inch on average with bullets springing up and down all over. I was shooting my 444 (same configuration) with a stouter load right besides with excellent groups, so I wasn't flinching, and my technique hadn't slipped. This same gun shoots a real stout load with 405's, 420's with no problem at the same velocity.

Should I have stayed with water quenched? Check lube? Not heat treat with gas checks on? (the latter was done with 444 and no acuracy loss)

Any ideas appreciated,

David

[Junior1942]

Sounds like a hold problem to me.

[Scrounger]

I was very anxious last night to try out a load I had worked up a couple of weeks ago. Its in my 95 Marlin 45-70 that slugs at .458 and has been firelapped. I got one hole accuracy a couple of weeks ago with 42gr. of H4198 (1980fps), and a heat treated 300gr. RCBS gas checked .460 bullet. The previous testing was done at 50 yards, and I moved to 100. The original test was done with water quenched, with last nights being heat treated. I use tumble alox, and wondered if my application was not adequate. No star on the end of my barrel. Best group last night was 4 inches, with 5 being the norm. Horizontal spread was usually 1 to 1.5 inch on average with bullets springing up and down all over. I was shooting my 444 (same configuration) with a stouter load right besides with excellent groups, so I wasn't flinching, and my technique hadn't slipped. This same gun shoots a real stout load with 405's, 420's with no problem at the same velocity.

Should I have stayed with water quenched? Check lube? Not heat treat with gas checks on? (the latter was done with 444 and no acuracy loss)

Any ideas appreciated,

David

Bad analysis, I deleted it. Should have kept the zipper on my lips shut...

[NVcurmudgeon]

Conventional wisdom says vertical groups=bad load. However, I would check to see if your hold on the target at 100 yd. is uniform. You didn't mention what sights you are using. I have found that bead front sights that may be OK at 50 go sour at 100 and beyond. If you have a gold bead, try smoking it. For my aged eyes, I have found a 6:00 hold on a BIG black bull with a smoked bead is easy to hold in the same place from shot to shot. Sounds weird, but a figure eight sight picture isn't that bad.

[Rrusse11]

Doc,
Sounds like you may be a tad too hard on your heat treatment, I'd be tempted to try 'em air-cooled over a GC, that and the other clue is the lube, or lack thereof. I've found single Tumble lubing works fine for up to 1500fps, but after that I give'em a double dose. Haven't been doin' much high speed stuff, over 2000fps lately, but I'll be going back to my pan lube approach for high velocity. Lars has got the wax!
If they're starting at nearly 2000fps, I doubt very much if ur hitting trans-sonic aberrations, RCBS.Load shows a BC of .207 for the RCBS 300gr FN, and it should still be doing 1634fps at 100yds. Interestingly even at 300 yds it's still past Mach 1 at 1135fps, though quite a drop of ~40".
Cheers,
R*2

[Dr. A]

curmudgeon,

I'm using a 2-7X Leupold. Now that you say that, I did have problems getting my very low velocity 400gr. sighted in. Would not regulate to the point of aim I needed I will try irons and another scope tomorrow. I had to have this thing worked on before. Its a veteran of many, many higher power rounds.

My heat treating was done at 420F for one hour with a quick icewater bath.
What do you think the hardness would be?

My 290gr. Mountain Mold out of the 444 was going 2300fps, and giving me a good 1.5 in. group with everything else being the same (except lube). It had two applications.

[Rrusse11]

My heat treating was done at 420F for one hour with a quick icewater bath.
What do you think the hardness would be?

Dr A,
Depends on ur alloy, and how much antimony,,,,,, I don't have a hardness tester, thumbnail works for me, but more than hard enuff I'd wager. I've run water dropped WW's over 2300fps with a GC no problem. Thinking about it, I'd say it's prolly a lube problem. And if you've got scope problems, wellllllll, that's another story, but if the same rifle/sight setup was shooting at 50, it's more than likely the boolit and inconsistent bore condition, ie. lack of wax/lube.
Cheers,
R*2

[drinks]

Just another possibility, did you check your sight picture for parallax?
If the scope is adjusted for 50yds, may have some parallax at 100.

[Dr. A]

Sounds like something to start on. See if I can get some beeswax here locally. I am surrounded by alfalfa/bees. I'm guessing they are plenty hard enough, and the lube is right on also. With the pan-lubbing, do you use an old shell casing cut out for a cookie cutter?

Thanks, guys for all the help. This really is a quick bunch!

[Dr. A]

Drinks,-thanks, there is on parallax last I checked.

[Rrusse11]

Sounds like something to start on. See if I can get some beeswax here locally. I am surrounded by alfalfa/bees. I'm guessing they are plenty hard enough, and the lube is right on also. With the pan-lubbing, do you use an old shell casing cut out for a cookie cutter?

Thanks, guys for all the help. This really is a quick bunch!

Dr. A,
Ayup to the shell case, lots of lube formulas floating around on this site, check out FWFL. Take a look at Lars' score on the beeswax, or find a friendly local apiarist. A bit of vaseline, some paraffin candle wax, a dash of STP, lots of beeswax,,,,,,,, melt it up, just watch for open flames, or nuke it. You don't need much to get started. You just need something soft enuff to smear into the grooves, for test rounds a finger will do.
Cheers,
R*2
Ps. No mention of ur sizing set up, but I lube and then use the Lee push thru dies. Just give the boolit base a wipe before seating.

[Bass Ackward]

The previous testing was done at 50 yards, and I moved to 100.

This same gun shoots a real stout load with 405's, 420's with no problem at the same velocity.

Should I have stayed with water quenched? Check lube? Not heat treat with gas checks on? (the latter was done with 444 and no acuracy loss)

Any ideas appreciated,

David



David,

What you need to do involves a systematic problem solving process. You might just get lucky (sorta) by isolating it to the scope. But what if that isn't it? Then where do you go next?

I always go back to solid ground as a first step. Your first two statements need to be verified. See if they are still applicable. Repeat the same load at 50 yards again where you first had success. Then I would try five shots of something else that was a known performer at 100 yards. Those two things will eliminate a lot of possibilities.

I would do these things prior to making the bold jump to replace scope if it were me; just because it is less hasstle than getting re-lined in twice. Once for the test scope and then the second time when you put the 2X7 back on.

I have a hardness tester if you really want to know what you are working with. You should know. Especially when you are working at those pressure / velocity levels. What if something actually goes wrong with the heat treat process sometime and you don't get as hard as you thought you would? I heat treated at 450 for a hour and quenched just like always and ended up just 1BHN harder than if I had air cooled. Luckily I test everything. It takes just two seconds to test them if you want.

Let's see where this goes.

[Dr. A]

I still have a large number of the original water quenched bullets, and over the noon hour I started making up some more loads including increased charges to go through tomorrow. This gun has two scopes. One for the lower range loads and one for the higher. Quick release rings makes things easy. I would have to resight it in, so I will try out these loads. I have some J-rounds made up, but usually use those in the Ruger. I do know the performance, though, in both guns. Thanks for all the help. I do have a Lee hardness tester, that have some missing parts thanks to my young son. :razz: My water quenched stuff was historically 18.

[Leftoverdj]

Need a bottle necked fired case to cut off for a cutter. .45-70 won't work because of the internal taper.

[drinks]

Dr A;
I use either liquid alox, usually 2 coats if I am not in a hurry, if in a hurry, I put a faint smear of hornady Unique case lube on the bullet before putting it through the sizer, [I make sizers the size I want], then put on LBT blue lube in what I call the sardine can method, although I now use a miniature loaf pan, the stiffining ridges in the sardine cans made some bullets tip over.
Just warm the lube to liquid on a hotplate with thermostatic control, do not let it smoke, place the bullets in on their base, I use a cheap pair of 6" forceps, watch the bullet, when the lube climbes up the bullet, take it out, set it on an aluminum pie plate , on the base, cools quickly, just flake any surplus off with your finger nail
I have had good results up to 2300fps with air cooled bullets, am now going to try some water dropped and have just received some linotype metal, hope to get 2500-2600 fps with these and no leading
I am shooting from .243 to .45-70 with these bullets

[Dr. A]

Drinks,

Is that the hard or soft stuff? I've thought of getting the Beartooth stuff. Are they comparable? Those Beartooth 300's I can get going 2500fps pretty well.

[drinks]

Over the years, more than 50, I have only used about 5 or 6 lubes, my great uncle's lard and lye soap, Johnson's carnuba paste wax, Lyman lube, bee's wax and graphited equipment grease, liquid alox and LBT soft blue.
The quick hot method is with LBT soft blue, I keep thinking of trying the medium or hard, but $40 for the 10 or 12 sticks is a catch, although I get great mileage with the way I use it.
Don

[Dr. A]

Well
Thanks for the help, guys, I got a list of rule outs and started at the top. Pulled remaining 10 rounds and relubed with alox. The original batch had been lubed immediately after quenching, and still had a slight amount of water on them. Relubing took the strinign away. Now to go for higher velocity!. :razz: