I'm starting below max's 5%, and working up loads. I know bullets, chambers, throats, elevation, temp, all have effects on pressure. But I've not worked with A-Frames that much, and was wondering if the mantel and construction of them are that much different and pressure increasing than the Partition? Any discussion is appreciated.
stevek

A-Frames result in noticeably more pressure with the same powder charges. It's not so much the interior construction but the softer copper and lead of the jacket and core.

That's interesting. It might explain why I get the same noticeable pressures with 196gr Woodleighs and 180gr Hawk .318 bullets, given the same moderate powder charges of 45gr of IMR 4064 or 45gr of R15. I'm comparing bullet to bullet with a given powder.

Given then the differences in pressure due to bullets, the guide would still be velocities given as starting and max for stopping, but also consider barrel length, most books show 26" barrels, mine is 24, should loose a little off max velocity.

Not necessarily. With "soft" bullets the maximum velocity possible tends to be less than with less-grabby bullets.

One illustration of this is Hodgdon's and Western Powder's load data. Often they'll include loads with the same powder for different bullets of the same weight. The listed pressures indicate how much extra pressure some bullets tend to create.

Along with A-Frames, among the highest-pressure bullets are other copper-jacketed, soft-core bullets like Woodleighs. The heavier Nosler E-Tips also create a lot of pressure for their weight, just like the pre-TSX Barnes bullets did.

Among the lowest pressure bullets for their weight are Hornady Interlocks and Barnes TSX's, especially in lighter weights for their caliber, because they have less bearing surface.

John, I still say that an article on various bullets and their "degree of grabbiness/pressue" would be both valuable and well-received.

Agree with all's said here, but confused some with the Barnes TSX's. I thought also with their rings they had less drag and bearing surface, but their manual #4 lists a max of 65gr of H4831sc, with other manuals at 5 to 6 grains hotter. Regarding MD's comment on velocity, I was referring to each manual's max velocity. Sure wish Nosler would make more of the Partitions at 250,I've more experience with them and the TSX's, and the Hornady's as general purpose ungulate shooting. I need to tweek some bullets prior to going to the range today.

carp,

Comparing the data from different manuals isn't nearly as helpful as comparing data from the same source, because the test barrels and the means of measuring pressure vary. Plus, the general skill of the lab can even play a considerable role, so some sources of data can be more reliable than others. I know of one lab that tested one relatively small .22 caliber centerfire and got velocities as high as a much larger .22 cartridge, at the same pressure levels, which is a physical impossibility.

Thanks for the reply John, appreciate your efforts working with the Philistines. I understand that the variables are increased with the different manuals, that makes sense. I went back to some of my older books, PO Ackley vol II 1980, it lists 4831, no designation IMR or H, at 71 to 75 grains for 250 gr bullets. Not that I'm going that high with my H4831. With this going on I did find and purchase a couple of boxes of 250gr Partitions, so I'm working with these, 250 Spire Points and 250 A-Frames, working up from 69-72 grains, we'll see how it goes. Thanks again to you and other replys.

You do know that Swift has a reloading manual?

Yeah, and it lists H4831 to 72.5 max, for 2610 or there abouts, Nosler's says about 71.5 for 2700something and Hornady says 73 something for some other speed. The troubling one is Barnes, they say 65 max, that threw me.

Ok,didn't know if you had the Swift manual.

Could be that Barnes is a longer bullet,could be,maybe.

It's a LOT longer, which is no doubt the reason for the lower maximum charge weight. The velocity listed is only a little over 2500 fps, indicating the powder charged maxed out due to the space inside the case, not pressure.

Thanks MD.

Elkhntr and MD, Yes the Barnes is longer, they don't discuss compression or load densities in their manual, Speer, Nosler, Hornady, and Swift all mention this. And while I'm finishing up a pound of H4831sc on Friday, I go buy a couple more and notice, it's not short cut anymore, just straight 4831. With the chunkier bullets I'm already packing it a little bit using the SC style. Back to trickling and shaking it down I guess.

I bought a box of 210 gr. Swift Sciroccos to try in my 338 RUM as soon as Swift came out with them, and before they had done any load testing.

I had shot some 210 gr. Ballistic tips and found they shot well at Nosler's maximum load data. So..... since the weight and shape were the same, I loaded the Swifts at Nosler's recommended STARTING load.

I had to drive the bolt open with a 2X4.

I called Bill at Swift and told him about it. He apologized for not having developed data for the bullet before placing them for sale.

I got similar velocities in my 7 RUM using the same powder loading for 150 gr. Scirrocos and 150 gr. Ballistic tips, but it sure didn't work for the 338.

Back from the range yesterday, with A-Frames 250gr at 71 grs H4831sc, vel 2441-2448, 72 grs and vel 2503-2517. The Swift book has max load at 72.5 grs of H4831. The Noslers 250 Part at 71 grs of H4831sc, vel 2451-2468 and 72 grs gave vel 2512-2533. The Nosler Manual has max at 71.5grs of H4831. Velocity was taken at 14 feet from muzzle with a CED Melenium crono. The Hornady 250 SpPts were right there with the first two. There were no visual signs(primers flat or powder residue, or case signs) of pressure, and bolt lifts were normal. Will stick with 72 grs of the 4831 just to see if the velocity stays consistent. I know this is contrary to the discussions above regarding the A-Frames and Noslers, but this is what I'm seeing in this rifle so far.

The rifle is an early 90's Ruger 77, push feed tang safety model, that is new to me. Was hoping to do better than 35 Whelen speeds, but I'll continue. The rifling and groups show promise if I keep off the coffee while shooting. I wanted 250's for this rifle as I have a 300 H&H that shoots 180's and 200's nicely.

I might give Reloader 22, 19, and that new 23 a whirl also.

My observations on least to most with a few premiums are: TSX/TTSX, Partition/Accubond/North Fork, and A-Frame.

Made it back to the range yesterday, but had problems with the crony, no readings and kept moving closer to the screens and got a few readings, that actually approached normal velocities expected. With RL19, 250 gr Hornadys, at 72 grains got 2650 to 2670, then I got too close, dead center and 1/4 inch into the crony. I never liked it anyhow. The good thing is the rifle is more normal, and worth working with. Now to find another crony. carp

I've shot two chronographs,welcome to the club.

carp,

Somebody once said, "If you haven't shot a chronograph, you haven't shot much."

What kind was it?

Elkhunter and MD, thanks for the replies. As I said, never liked that crony anyhow. It was a Competitive Edge Dynamics, about ten or eleven years old, would not read in low light situations, direct sunlight was problematic also. So now I'm looking again, would like to keep it simple, I like to write stuff down in notebooks, so I don't need to plug into other technowizbang stuff, just check muzzle velocities so I know I'm not out of bounds with loads. Our range has 300yd stands and that's all I need for my rifles.
ps. The Hornady did its job, might've expanded a little too much on the backside.

Carp,I use a Pro Chrono. They are not expensive and have had this one about 8-10 years +/-.

Elkhunter, I was noticing one of theirs, about $100 and looked like it would do what I need. carp

I have several chronographs, but TWO of them are ProChronos, because I use them the most and like to have a back-up, just in case one meets with an accident. So far I haven't shot either one, but a gust of wind did tip one over, and it had to be sent back to the factory for repairs.

Thanks for the input, stevek

Had that happen also,didn't break the chrono. I just don't shoot when it's windy.

Although gusts do come up.

Jinx, now you are destined to plugging it soon!



I've blown the rods and plastic off of mine a few times but still missing metal!

It's a Chrony refurb

Mike

Yup.


Haven't done that,but the wind blew it over and bent the rods,still useable. The plastic finally wore out and ordered new ones last year.

All I can say now is it won't be the first time!

And not the last!

I have a pro chrono also. I've compared velocities with a friend's Oehler and it's been real close. I've had mine for 3-4 years now.

Carp, your velocities are running pretty close to my 338. I'm getting 2600fps with 74grs H4831 and 250 partitions.

My Hornady book, 9th edition shows 2650 fps with 75.3 grs H4831 and 250 Interlocks. I'm going to try those next.

Terry I've not gone that high with the Partitions, Nosler book has them maxed out at 71.5grs of H4831, I went to 72 with the Nosler's and the Hornady's I've gone to 74. You might be able to wring out a little more velocity with RL19 or 22 and the Nosler. I would like to try the new RL23 but don't know if I can stuff enough of it in to make a difference. I'll have my new chrono next Monday, and will wait 'til then to shoot the 338. Will come back then with any pertinent info.

Put some Rel 15 or 17 or 760 in there and watch them fly.

I have done real well with RL22 and the 250 PT's from my Pre64 Alaskan. Pretty easy to get up into the 2750 range with it's 25" barrel. I used Nosler brass and CCI250's. Accuracy was pretty good as well. Might be better since I put the McMillan on it as well.

Plan to give 23 a try when I find some of it.

One of the techniques I use when trying to figure out which powder might get the highest velocity in a particular cartridge/bullet combo is to look up all the data. A lot of it is available for free on-line these days, but I also try to buy the latest manuals as well. The only one I don't have right now is Swift's, but do have their first manual.

I just did a typical search for 250's in the .338 Winchester Magnum, using 10 sources, and with two exceptions the maximum velocity for 250-grain bullets was somewhere between 2621 and 2700 fps. (All the test barrels were 24" or close to it, common these days.)

The Nosler (2780fps) and Vihtavuori (2555). It's interesting that Nosler's data lists 71.5 grains of H4831 as the fastest load, exactly the same powder and charge as Hodgdon, but there's 125 fps difference between their velocities. We might assume this is due to a "fast" barrel in the Nosler ballistic laboratory, but the two labs also use different methods of pressure measurement.

Aside from the outliers, only two powders were listed more than once as producing the highest velocity: H4831 got three listings (including Nosler and Swift) and Reloder 19 two. The powders listed once were Hunter, Norma MRP, Magpro, VV N165, and RL-17. Hunter had the 3rd-highest velocity, 2665 fps, after Nosler's 2780 and Hornady's 2700. Reloder 17 tied with Reloder 19 at 2664 fps for highest velocity in Alliant's data.

Based on this, H4831 and Reloder 19 look like top choices, with Hunter and Reloder 17 also worth considering.

Of course, any powder can produce much higher velocities if we leaned on it. When I was hunting a lot with the .338, I used up to 75.0 grains of H4831 and the 250-grain Partition, for 2750 fps in a 22" barrel, and never encountered any pressure problems even when hunting in Africa at temperatures up to 90 degrees F. But that may have been an exceptional batch of H4831.

However, I will note that one of AGW's favorite powders, W760, which he mentions as very fast with 250's, did OK but not great in the data search, whether called 760 or H414 or Accurate 2700 (they are all the same powder). Hodgdon lists 2622 with 65.0 grains and the 250 Partition as the top velocity, and Accurate lists 63.0 for 2547 fps with the 250 Sierra GameKing.

Regarding getting into the more medium burning powders, Alliant's site lists the RL 17 with the 250gr Speer GS, I've thought of that one as well. But I try and go with powders suggested and if I run out of room go down the list for a little faster powder. Hornady has this published in their manuals. But it is not absolute, as the burn rates change in differing calibers or conditions. So it is a general speed of burn rate chart, it does not hurt to be conservative. Another source for 338 WinMag info would be in Handloader 2007, Feb and April issues, by John Haviland and Brian Pearce.

Been busy with Spring and chores, but got a Spring Bear tag so I'm back at it. RL 22 75grs and Nosler 250 Part, in a fresh DBC barrel, Ruger M77, the first two shots were the low and high, throw those out and the next 8 were 2677-2699, which seems to jive with where it should be. Got some H4831, 72grs, for today. Fully free floated the barrel and bedded the lug and tang areas, will try some tip pressure with a card and see if that improves rifle to wood. Interior of stock has spar varnish sealed, the exterior is done in WaterLox Exterior tung oil base, sanded in and rubbed in 3 coats. Thanks again to all for info, new ProChrono works fine. If I figure out how to post pics I'll do that. stevek

Evidently all lawyered up and conservative. (I keep hearing the 340 is obsolete these days based on some of the Win Mag loads being touted across the electro-net.)

I wouldn't call the 340 obsolete as it is one of the few that does what is both claimed and rumored.

When I handload, I commonly go overboard meaning instead of selecting a few bullets to cover most needs, I tend to load for everything on the shelf which usually means a dozen or more bullets in varying weight and nearly that sometimes, in powders.

It takes a long time and an awful lot of chronographing before I am done, then I repeat it all again when the next rifle in like chambering comes along.

I have far more commonly found the medium/slow powders more reliable and uniform in performance than the slow powders.

Coming from the "sunburned country", I never experienced the temperature issues others have and when I try to replicate them, fail, which is why they still appear in my recommendations.

Whether .25/06, 7x57, .30/06, .338 or .375, I like the mediums and find they work best at peak pressures as the velocites and groups indicate.

I used a lot of AR 2213 in Oz as it worked very well in the magnums but in the US with the current version marketed by Hodgdon, I don't get the same results others do to the point I will likely drop it when my stocks dwindle.

I enjoy reading others experiences but am amazed at how many are different to mine which are commonly learned in a variety of rifles which as I stated, are replicated in the next rifle that comes along.

All in all, I am enjoying this thread.
John

Whoa, no lawyering here, old construction supt here and want nothing to do with lawyering. 30+ years with buildings, no real injuries, happy owners, architects, tradesman, anything I blow up, I blowup. Right now I'm OK with what's going on and the 338, but working on cutting down the varibles, bedding, bore coating is getting better, and things are starting to smooth out. Might cram another gram or two with H4831 or stick with the RL22, as our weather is pretty stable, rare hot days here and don't worry too much with hots and colds. 2650 to 2700 is fine. But all the info is still good.

It's actually nice to see so much sane banter regarding a cartridge which obviously works so well within the parameters of its design. It almost seems, sometimes, as if the good old 338 is leaned on harder than so many others in order to make it become another great cartridge of the same bore size, the 340. But, no surprise, a 250 started off at 2700 or so is just as effective as the same basic pellet at the same speed in the 358 Norma. And while some will advocate for another 150 or so, it has never seemed like a winning pursuit to take a dangerous game suited cartridge, and push it to potential bolt-binding pressures. But what do I know?…….(other than that I haven't had my kneecaps gnawed off by the local bruins yet.)