I understand about our litigious society in re to shooting these days, lawyers, etc., but things have become, IMO, ridiculous. Was working up a load w/100 gr bullets & H4831 in a new 243(26 in. bbl). Max load was 42.5 grains,(Hodgdon data) which seemed low compared to my past experience. Loaded three at 42.5 (Hodgdon's max load, yeah I know, don't preach), 3 at 43.0 and 3 at 43.5 (one gr. OVER their MAX). First loads gave 2700 fps, cases were sooty at the necks, not enough pressure to open necks. Skipped the 42.5 loads and went on to the 43.0 loads which were pretty much a duplication of the first loads except the vels were 2770. Case necks weren't blown out, primers looked like they were fired in "squib" loads. This is supposedly 1 gr over their max. Pressures couldn't have been even in the 30-30 range. I've burned out two 243 bbls and am working on the third, so I've got a little experience with the 243 Win. Found some loads in the last IMR pamphlet in which MAX loads with the same powders and 100 gr bullets used less powder in the 243 than the 250 Savage. The SAAMI pressures for the 250 are considerably lower than the 243. Yes, I've heard about "pressure spikes" and a lot of other things in re to the 243, but never experienced any of that, and used to load things pretty warm(no more). Seems like the reloading data people need to go fishing. Can't figure out how they got 49,000+ cup's of pressure with that load. Had to be one tight chamber. They're turning the 243 into a popgun. Other data producers seem to have followed suit. That 42.5 gr load isn't even a good starting load in my gun. Can't believe it'd be THAT much different in other chambers. I always work up loads, but this is ludicrous. Sorry for the rant.

I have to agree with you...for some reason (and I heard an explanation once) the data on 100 grainers really really varies. Plus add to that is that some H4831 has really gotten to be a slow burning powder--some is even slower than re22. I think I've seen load data on 100 grainers on re22 varying from 42.5 to about 46 and I think the light data has to do with case capacity and compressed loads. Just running a 46 grain load past quickload with 46.0 of re22 shows a pressure of 54,000 so you are certainly right that there are some wimpy wimpy loads being published.

John Barsness has covered this a couple of times at 24hcf. It’s not so much pressure “spikes†in the .243 as much wider pressure swings; these are manifested mostly in the heavy bullets like the 100 grainers. A quibbling diffrence, perhaps, but it is the reason why data is kept so low.

In a normal string of 10 rounds of any particular cartridge, all loaded the same of course, the pressure difference between highest and lowest might be 5,000 psi. In the .243 it might be 10,000 psi. The 7mm Rem. Magnum is another cartridge which has unusually wide pressure swings like that. No one knows why this is, they just know that it is real.

I was a bit put off the .243 for a while after I learned this as I was sure I needed to achieve 3050-3100 fps like the books say. Nowadays I’m perfectly happy to load it to 2900 or 2950 fps and so even if the pressure spread is 10,000 I figure I’m not going to break the 60,000 psi mark.

Once again, a good chronograph is the best tool outside of a pressure barrel for the average handloader.

Thanks for the replies. If I'd been getting 2850 fps or so would've been one thing, but the velocities I got were: 2700, 2700, 2716 - nice consistency, but a little slow! Whatever happened to the SEE fears of using reduced loads of slow-burning powder? H4831 certainly qualifies. The starting load in Hodgdon is 39.0 grains! Huh? I guess it's OK to blow up your gun as long as you use a reduced charge. BTW, just to make double, double sure I didn't do something stupid like look at the scale wrong, etc., I just loaded a round with the 42.5 gr. load and popped it off. Same thing, soot and neck didn't open.

my load data puts 100gr bullets H4831 at 41 to 46grs max???????????
243AI I shoot 90 barnes and 95 bergers H4831 @ 49 grs>

Gimpy, with that 26" barrel you can use a little slower powder than my 243 with a factory 22". I quit using H-4831SC and started using IMR 4350 and Hodgdon's Varget and am getting higher velocity and better accuracy with the 100 grainers. I clocked it loaded with 40 grains of IMR 4350 at 2950 ft/sec and no excessive pressure signs. I didn't use to like this caliber much until I started using a little faster powders. I put 5 shots into a group at 100 yds with Varget that could be hidden behind a dime and started a love affair with this caliber that almost matchs the feelings I have for 30/06.

This is getting to be a dilemma for reloaders. Maybe lawyers are writing the manuals as well as designing the rifles. Chronographs are about the only link to honesty remaining. I don't approve of red lining my loads, but I do want honesty in the load data presented to me. Best wishes.

Cal - Montreal

Gimpy, in most 243's I've had, a max book load of H4350 will push a 100 grainer between 3,000 and 3,100 fps no problem in a 22" barrel. I like the 243...

you should mabey try some 7828 its real slow .i have used in all 4 of my 243s from 26 " tubes to my ruger ultra light wieght with a 19" tubewith a 90 gr speer and 49 gr it chromy at 3347 also with 48 g and a 95nbt iit will be 3345 have also tried 50 gr but got a real flat primer. these all are way over max but were worked up to using a chrony and a pressure gauge

H-4831

.243 with 100's:
H-4831 From 36.7 grains to 46.0 grains
Remington 9-1/2 Primer

.250-3000 wit5h 100's:
H-4831 From 35.0 grains to 44.0 grains
Remington 9-1/2 Primer

I have shot up to 44gr. of H4831SC and everything was fine (Sav. 110, 22" barrel). At 45gr. I had a few cases that were difficult to extract/sticky bolt lift so I abandoned the load. This was in 90deg. or better and from what I understand, even temperature insensative powders such as H4831 can show increased pressures in hot weather. I was shooting 100gr. Remington PSPCLs by the way. I now have loaded up some 243 loads using IMR 4350 and will try them tomorrow. IMRs "new" data lists and increased charge on their website with IMR 4350 and 100gr. bullets. I have abandonded the idea of trying for high velocity since I don't need it and it's easier on the gun.

If you want to see something really disappointing, try chronographing some 100 grain .243 factory loads. In shorter barrels, some of them hardly break 2700 fps. Back in the "good old days" factory .243's easily met their 3050 fps advertised velocity if you had a 24" or better barrel. Coincidentally, my Sako (23") seems to have a "fast" barrel and my loads with original surplus 4831 behind original Nosler Solid Base 100's yield 3100 fps with no discernable brass degradation in multiple reloadings.

For whatever reason, an "urban legend" has developed around alleged pressure inconsistancies inherent in the .243. These urban legends seem to be having an effect on published loading data. Having worked extensively with a number of .243 from several different manufacturers, I don't buy it. I've never found any behavior with this cartridge that is inconsistant with the behavior of any other modern, high-intensity cartridge using powders in the medium to slow burning range -- 7mm Remington included (now THERE'S a disappointing factory load!)

One respected gunsmith who used to contribute regularly to this forum once commented that he'd seen more "unexplained" gun blow-ups with the .243 than with any other caliber. I don't doubt this, but after all, the .243 is a popular and very common caliber and the limited universe of guns that one smith sees can't possibly be an accurate statistical representation of all rifles.

Others have observed that a number of European-made rifles generate excessive pressures because they used a rather tight bore, perhaps as small as .241" or even .240". While this sounds plausible on the surface, a bore that is only .002 or .003 smaller than the bullet causes an insignificant (and certainly not devastating) increase in pressure.

There is no reason to treat the .243 any differently from any other "modern" cartridge. When data found in whatever source shows powder charges that are disproportionate to other calibers and bullet weights, then take them with a grain of salt and work up your loads as you would (should) with any other caliber. That means spending less than the cost of three boxes of premium bullets for a fundamental chronograph. No handloader should be without one today.

quote:

Originally posted by Gimpy:
Thanks for the replies. If I'd been getting 2850 fps or so would've been one thing, but the velocities I got were: 2700, 2700, 2716 - nice consistency, but a little slow! Whatever happened to the SEE fears of using reduced loads of slow-burning powder? H4831 certainly qualifies. The starting load in Hodgdon is 39.0 grains! Huh? I guess it's OK to blow up your gun as long as you use a reduced charge. BTW, just to make double, double sure I didn't do something stupid like look at the scale wrong, etc., I just loaded a round with the 42.5 gr. load and popped it off. Same thing, soot and neck didn't open.

If one is using shorter barrels, use faster powders....IMR 4895 and 4064 will easily give me 2850 fps in a 20 inch barreled 243...however as has been discussed many times... 150 fps is not going to make or break a hunt...

I really think that factory loads, keep sneaking down, just for liability in our sue happy society...

Where you talk about soot on the neck and the neck not opening.. I also wonder if your 243 is longer throated than you are seating your bullet?
Sounds like it to me....

Once again, if you are using a Model 7, try faster powder... 4831 SC and a short barrel are a contradiction in concepts...

I really think 4350 and 4831 are so popular with manufacturers because it fills the case, ( you burn more powder, so they sell more) and then the pressures are lower and so there is less margin or error potential for the average nimrod at the loading scale.

If someone wants to follow that philosophy in a 243, then look at IMR 7828.. fill the case, seat a 100 grain bullet and go hunting....

I myself spend time paying attention at the load bench, instead of having the factories and society trying to make it all as idiot proof as possible... I avoid being treated like an idiot... that is what God gave me a brain for... SO I use it!

cheers and good luck...
seafire

Seafire said:

Where you talk about soot on the neck and the neck not opening.. I also wonder if your 243 is longer throated than you are seating your bullet?
Sounds like it to me....


This rifle has a shorter throat than others I've had, for instance I can touch the rifling with 70 gr TNT's which're seated in 3/4 of the neck. The 100 grainers are touching the lands and seated well into the case. No, it ain't a long throat. BTW, this is a 26 in. bbl. What I've evidently got (alluded to by kraky) is a lot of sl-o-w-w H4831, I guess. I'm working up 'til I get pressure signs & back off and see where that leads.

Ricciardelli: checked your pages, already. BTW, moved to Idaho, not Montana. You scared me. - NOT. Remember me?