In Cartridges of the World there is a comment about ballisticians getting erratic performance
with the 243 Win. Anyone know what they mean? Are they talking about safety or accuracy?
I've had problems with accuracy but I still would like to know what they are talking about. Is
there a secret to reloading the 243 which I'm not aware of?

No, there's no secret. It loads just like any other rimless bottleneck high-intensity centerfire. Myths like this usually have as their source someone who misread the data, used powder of the wrong burning rate range, or had a "deviant" gun.

6mm's of the capacity of the .243 and up work best with powders in the slower burning range, especially with the standard deer bullet of 100 grains. I use a "slow" lot of H-4831 for all of my .243 loads with bullets of 80 grains and up. I have three .243's, with barrels of 20, 23, and 24 inches. All of them are very untemperamental and shoot a wide range of bullets and powders well.

Doc L,
You'd have to give us more information. What make of rifle, your barrel length and diameter, what you shoot in it etc. I've had a .243Win. for many years and find it is a reliable performer for everything from woodchuck to deer. Is your action glassed, your barrel floated, how heavy is your trigger pull? Are you shooting from a bench? The list of pertinent questions is pretty long. Give us a litle more to go on. Best wishes.

Cal - Montreal

My .243 is a M70 Fwt that I purchased with money given me for graduation from college in 1957.

I find it easy to load for and have had no problems. I use only IMR 4350 in it. I have tried other powders, but always came back to 4350.

I have some difficulty believing that some cartridges are inherently inaccurate. I realize that some may be a little more accurate, but most of the stuff I read is baloney. Get good bullets, work up loads, and shoot them in a good barrel that is well bedded, and you will have an accurate gun.

Jerry

A search here on the 243 will find that Jack Belk has come down hard on the 243 Win saying that he has seen more blown up guns in that cartridge than any other. On another forum Barnsness has said that lab(s) have found pressure spikes with it and the 7mm Rem Mag. An old Lyman handbook mentions tight chamber necks in some imported rifles.

I have had both cartridges and never had a problem with them. But this internet allows information, right or wrong, to get around.

In loading the 243 Win and I have used just Sierra bullets and IMR 4350, 4064 and some 3031. I burned out 4" of a SS barrel on mine using a load over book max of IMR 4350 that got the 75 gr out at 3600 fps. Never did I see a pressure problem.

Load you a few cases with 41 grains of Varget, 70 grain Nosler BT and a Federal 210 Match primer and seat the bullet just touching the lands!! If it won't shoot it will be the first one in a few that wouldn't!! For a milder load, 36 grains if IMR 3031, 75 grain Speer HP and a CCI BR primer of CCI 200. A boatload of groundhogs have fell to this one!! And the neat thing about this load is that you can see the bullet hit him because of the light recoil!!! GHD

Seems like every one has had good performance out of the 243; and I have too in the past.
The problem gun doesn't yield to any classic solutions. I built this gun in the early '60s on a Herter's (BSA) action and made a rock maple stock for it. Poor shooter from the start. Put it away until last year when I tried it again after replacing the barrel with a Shilen CM #3 1:10 twist 24 " and glass bedded then pillar bedded it. The trigger breaks at 3. 5#. The chamber is to SAAMI specs according to my measurements and another gunsmith fitted the barrel and chambered it. It had a bastard measurement for the threads so I had him do it. I did a crown job on if after trying every load I could find and finally got a 1.75 group with a Berger 88 gr. and 40.8 grs of H4831 Rem brass, CCI primers, case length to specs and shot off a bag.
I,m going to switch scopes as a last resort before I start cutting the barrel off to hopefully find a sweet spot. For grins and giggles, I tried a 105 gr. Berger VLD in it and it threw it them sideways.
This is obviously a "deviant" gun but I'm too stubborn to give up on it. I've already tried all the things I know (50+ years of gun work) and this is the first time I couldn't get any favorable results from any rifle by using proven methods.
Thanks for the advise all of you contributed. I just was stabbing in the dark hoping to get a lead I hadn't thought of. The pressure spiking was probably what the book was implying.
I hate to condem the BSA action but I have just about ruled out the reloading problem. I appreciate all of your input.
Doc

If you have not switched scopes yet it's time. Most cartridges have about the same accuracy so it's not the 243 as a cartridge.

Try shooting it with just the front guard screw tight. Leave the rear screw loose. There are lot's of things to check. Just keep at it.

You can always call Sierra on the phone too.

If you tell us what powders and bullets you have on hand maybe someone will suggest some pet loads but it's usually the bedding, scope or barrel.

Doc L.,

Welcome to the forum.

We've had quite a few problems with the 243 Winchester, and we know what is causing it.

All the ones we've had have been with East European made rifles, that have very tight barrels - groove diameter is down to .239.

These are the only times I can remember any problems with the 243.

Just my 2 cents, but the only problems I have had with the .243 is making sure I check the case necks for thickening. Seems like the necks would get too thick after just a few firings, much quicker than with other calibers I shoot. Accuracy really goes to pot.

Doc L.
I have loaded for 2 different 243's, a Rughr No1 that was very finiky and a Remington Mod & that I only shot the following load in as it shot so good I saw no reason th try any other. The mod 7 shot such small groups at 300 yards that I will not even mention them. This load was worked up for the No1 and it shot very well, killing antelope at 350+ yards.

100gr. Sierra Spz 42gr. of IMR4350
or if you want a little stronger bullet
95gr. Nosler Partition 42gr. of IMR4350

Start at 38gr. and work up. 40gr. shot almost as good as 42gr.
Hope this helps

My vote is for Speer 100gr BTSP with 43.4gr IMR4350 with CCI250 primer in W-W cases chronographed at 3,040fps out of 22"bbl. Browning.
Gets sub 1/2" groups at 100 yards consistantly.
No pressure signs but as usual work up from below
with your rifle. This is a good sturdy bullet that
works well for deer and coyotes. Second choice is
IMR-4831 with the same bullet.
O.A.L is 2.36" in my rifle. I have not had any
problems with reloading these two powders in .243
or any other caliber. Good shooting! BLR7