Load development for a barrel burner

[westernrover]

I want to develop a load for an overbore magnum barrel burner.
What method is going to get me a good load without too many cartridges expended?
Can I get good data from new brass (Nosler), or do I need to use once-fired and shoulder-bumped?

 

[Mk-211]

Posting the caliber will help guys here to help you out.

You might be able to have the chamber set back at some point in time. It's just inevitable that an overbore caliber will burn out the throat.

 

[WestKentucky]

I would say it most likely depends on what you intend to do with the rifle. Barrel burner is kinda relative for that. If it’s a hunting rifle that you want 500 yard 2 inch groups with then that’s one thing. If you want a 2 mile gun then that’s soMething different. If you want a PRS rifle then that’s once again a new scenario. From my understanding barrel heat is as big or bigger bigger concern than heat in the shot. Get the barrel hot and rifling strips much faster, so cool between shots and try to sight in quickly when you find a load it likes. Be conservative during load development.

 

[westernrover]

It's a pre-64 264. It's for hunting. With Nosler factory loads, it's grouping sub-MOA. I want to load a mono for it, and I'd like to have as much precision as it can deliver for those pronghorn that won't let me get closer than 400 yards. If I do it right, I won't shoot out the original barrel on game shots, not in my lifetime, but if I don't have a good plan, I could waste a lot of its life.

 

[AJC1]

Strict adherence to one of the well developed methods like satterly is going to get good results with the minimum waste. Your ability to wait for barrel heat to dissipate will help a lot.

 

[westernrover]

Right. Satterlee, Audette, OCW, ladder, ?

I'm thinking of using 4831SC, but I wonder if I would get better results with a compressed load of a slower powder like H1000, Magnum or Retumbo. 7828 is another choice that would be like 4831SC in that it I'd hit the pressure limit before the charge was compressed. With monos, the bullet weights are low but the bullets relatively long. I could be shooting a 100, 110, 115, or 120. The heavier ones might not work with the 1:9 twist.

 

[JFrank]

https://www.longrangehunting.com/threads/tuning-for-long-range.192998/

 

[Bcwitt]

Go mild. Treat it like a 270Win. Extra powder just wears bore w little velocity increase.

 

[lightman]

Do some research or asking around for other shooters pet loads. Some loading manuals list their most accurate loads. It may not be in your rifle but most likely will be close.
Or pick a bullet in the weight that suits your purpose thats friendly with your rifling twist and a medium to slow burning powder.

 

[westernrover]

Anyone care to offer more specific advice?

Let's say I start with 120 grain Barnes TTSX and 4831SC. Barnes data shows 56.8 grains as a max load for 4831, but they don't indicate if that was the max case capacity or max pressure. I should be able to get more of the SC version in the case and Quick Load suggests my pressure wouldn't be too high.

Suppose I start at 56 grains anyway. Or maybe I give some more breadth to find a node and start at 55.8 grains. Do I load 0.1 grain increments? or 0.2 grains? Let's say I load
55.8
55.9
56.0
56.1
56.2
56.3
56.4
56.5
56.6
56.7
56.8

Do I load one cartridge each or two? I have to balance barrel burning with my desire for good data. I could load a wider range of charges, say starting at 55.5, and I could load over 56.8 -- Quickload suggests it's reasonable and I'd just have to watch for pressure signs as I go up. If I didn't do this, I could be missing out on a node up there. But the wider range of loads I test, the more I'm using up my limited barrel life. If I want to do more than one bullet or powder, it all gets multiplied.

Suppose I find a node between 56.4 and 56.6. Now do I see if I can get low SD's with 56.5 -- how many cartridges do I test for SD? 3? 5? If the SD is 20, I'm not happy and I have to look for a different node. Is this a good method?

If I find a node where I can get single-digit SD, do I approach seating depth next? Published COAL is 3.225". Do I go in, out? By how much and what increments? How many shots do I take of each seated depth to gauge accuracy? 3-shot groups? 5?

 

[Varminterror]

How far do you need to take this? If you just need low SD’s and cloverleaf groups for 3-5shots, then you can get it done in ~34-40 shots.

Satterlee, Audette, Newberry. Any of these 3 will work, Satterlee with less burden. 10 to foul, 8-10 steps of charge weights, three times.

 

[HowieG]

I got a deal on a light 300 WSM that needed a little gunsmithing to make it good. Savage Model 14 American Classic. I knew it was going to be a barrel burner and also NOT gonna be particularly fun to shoot off a bench. Normally, I use a ten round ladder method for development, but for this one, I used the LHIGL method. For those not famliar, that's the Let's Hope I Get Lucky method.

First, I decided what I would theoretically use the rifle for. Probably deer and pronghorn out to say 400 yards. It sure as heck wasn't going to be a shoot 200 rounds off the bench target gun. Then I looked at what I had to work with. IMR 4064 has always worked good for me an I have lots. I figured a lighter bullet moving fast would be great for the game intended and light bullets kick less. I happened to have some 125 Ballistic Tips. Good to go.

I eyeballed the potential charge weights and picked a level with good velocity without being overwhelming. That was 60.5 grains IMR 4064. I loaded up 18 rounds (all the brass I had) and fired 18 rounds (scope sighters plus some 3 round groups) in anger at a 100 yard target (15 rounds over a Prochrono DX). Average velocity was 3370 FPS. ES was 41. SD was 10. Groups ran around one MOA or a little less. I was pretty darned surprised.

Barrel saved, shoulder sort of saved, and development done. Load recorded. Rifle put away and not fired since. That was October 8, 2021. That LHIGL method worked pretty darned good. I might actually hunt with the gun if I can get my hip to work right again.

 

[westernrover]

10 to foul, 8-10 steps of charge weights, three times.

10 foulers eh? So I can probably expand all my brass that way. I have 20 fired cases already. I could buy another box of 20 Nosler factory loads for foulers or a box of 50 brass and load them up for foulers. Otherwise, I'd be shooting some new brass as part of my tests.

Now if I shoot the 10 increments 3 times, I'll be able to see where the nodes are with at least some consistency, and I'll have at least 3-shot SD data and group sizes. That is if I load up 30 and shoot them in groups. If I do that, and there is a problem with the primer/powder combination, I will have spent 30 before I see it. If I shoot 10, 10, and 10, I could see any problems in the first 10 before I continue, but I won't get meaningful group sizes. Whichever way I do it, I still won't have looked at seat depth.

 

[Varminterror]

Whichever way I do it, I still won't have looked at seat depth.

Unless you’re competing for score with rankings won or lost by a thousandths of an inch, you really shouldn’t need to.

 

[HowieG]

10 foulers eh? So I can probably expand all my brass that way. I have 20 fired cases already. I could buy another box of 20 Nosler factory loads for foulers or a box of 50 brass and load them up for foulers. Otherwise, I'd be shooting some new brass as part of my tests.

Now if I shoot the 10 increments 3 times, I'll be able to see where the nodes are with at least some consistency, and I'll have at least 3-shot SD data and group sizes. That is if I load up 30 and shoot them in groups. If I do that, and there is a problem with the primer/powder combination, I will have spent 30 before I see it. If I shoot 10, 10, and 10, I could see any problems in the first 10 before I continue, but I won't get meaningful group sizes. Whichever way I do it, I still won't have looked at seat depth.

I shoot one straight ten round ladder at a point target at 100 yards. If those ten rounds with varying powder charges (.2 or .3 grains is what I like) go into 1.5 inches or less, that tells me the combo has potential. If the ten spread out to 2.5 or 3 inches, I scrap that combo and try another bullet and/or powder. I also look at velocity nodes of course. If those ten rounds go in pretty tight, usually the extreme spread looks pretty good too considering the varying powder charges. I only move on if I see potential.

 

[GooseGestapo]

Given it’s a Pre-‘64 Winchester M-70 in .264winmag, There is approximately 60yrs of evaluation and data available.
I’d research old articles and current load manuals specific to YOUR COMPONENTS.
Primers will be the least significant parameter, but nevertheless I’d just use the Federal 215 Large rifle primer.

H4831 is an excellent choice. However I’ve almost uniformly gotten better results from Reloader22.
Even better accuracy is had from my .257wbyMag, a near spitting image of the .264, with Reloader25. Not being able to source RL25, I’d try IMR7828.
If there is a trend, it’s this:
Extruded powders give better accuracy, generally.
Spherical powders give higher velocities.
Slower powders use higher charge weights
Higher charge weights erode barrels faster
Shooting faster heats barrels more, erodes barrels faster...
The three shot groups “tendency” arose from writers/editors trying to save their barrels.

Even with load development, the .264 will take 1000-1200rds to start seeing a diminishing of accuracy due to barrel wear.
Given that the monolithic bullets you mention start at about 80cents A PIECE! It’ll cost you over a thousand dollars to wear out that barrel!

After researching your bullet, select a powder and use the TLAR method.
(THAT LOOKS ABOUT RIGHT!)...
It more often than not works well for me...

I once was looking for a reduced load for my .300RUM.
I have an abundance of IMR7828, an extruded powder on the faster side of suitable powders. I wanted .300H&H approximate power. A starting load of 84.0gr looked to deliver it.
I didn’t take into account my 26”bbl. It hit 3,180fps w/180gr bullet and first three “touched’ at 100yds.
Load development took three shots! (Though about 150fps faster than my target velocity).
That IS a reduced load! Consider 98.0gr of Retumbo hits 3,350fps...

Enjoy the process! If you didn’t like shooting and reloading, you wouldn’t be here!

Though I’m not so sure how much I’d enjoy shooting $1.00+ bullets! I’m still loading and shooting bullets I bought for less than 10cents each...

 

[AJC1]

So if you wouldn't mind a little internet posting, I would post on hammer bullets on Facebook and see if someone there has a good working combination. Those guys seem very eager to help and focus on the mono bullets you desire. I have never seen a Barnes support page but they may have one. I might also try and contact one of the ftr guys that live and breathe 284 and see what they have to say. I just watched a "winning in the wind" ftr shooter and content creator develop a ttsx load in 308 for hunting. That's not direct advice but areas where you may find real helpful knowledge. Heck throw some clay at Eric Cortina and see if he replies.

 

[Slamfire]

My F Class friends all have barrel burners. One bud, shot a minimum number of 6 X 47 (I think) to zero the rifle, shot 400 rounds in competition before going to the Nationals. I can't remember the total number of rounds he could fire at the Nationals, might be 600 rounds. Before the tube had a 1000 rounds, it puked. Bud was cleaning the thing between relays, that did not help. He went from like upper 10 or 20 to bottom. I looked, he was just above those who did not fire! He was very frustrated.

I talked to one shooter who owned a 264 Win Mag and it is my recollection his barrel started keyholing before 800 rounds.

I would recommend trying to find where the throat starts. The last pre 64 was made 59 years ago, do you have a good idea how many barrel burning rounds have already gone up the tube? I would not try snakes and ladders, or any of that. Extensive shooting will move the throat, and then, you are back to square one. Or maybe, barrel two. Ask friends for loads, look on the web. You will see some patterns where shooters have good accuracy with certain bullet weights and powders. Decide how closely you want to copy and load 20. Get your rifle zero'd and if the groups are 2 MOA or less, live with it. I know accuracy levels like that blow dreams of over the horizon shots, but 2 MOA will get most any North American animal out to 300 yards. And I am going to say, 300 yards is a long way out there.

Magnum cartridges in hunting rifles are never going to produce target grade accuracy. There is simply too much bending and flexing going on. And if the truth be known, flinching. I recently took a 300 Win Mag to the range, and I quit around 30 to 40 rounds downrange because I hurt.

The heck with recoil.