Trying to work up a load with a .243 mystery bullet

[deerslayer303]

Hello all,
I bought a bunch of .243 Win 80 grain bullets (probably pulled) off of gun broker when .243 bullets were made of unobtainium not so long ago. They look like a Remington core lokt bullet, jacketed soft point but not alot of exposed lead on the tip. So I'm loading them over 37.5 grns of IMR 4064 (starting load) according to my Lee Modern reloading manual. But to get to the MIN COAL of 2.635 the bullet is NOT to the cannelure on the bullet. The round does chamber and the breech of my CVA Scout closes just fine. Seating the bullet to the cannelure results in a COAL of 2.54 ish. I didn't spend much time on measuring with the bullet at that depth. I just pulled the bullet and seated another to 2.635". I would like to use these bullets but I'm thinking I will have to crimp them out of the groove. What are your thoughts on this situation.

I do have some Hornady 80 grain GMX bullets But I don't have any of the powders listed in my Hornady manual under that bullet. The only powders I have is IMR 3031, 4227, and 4064.
Thank you for your time.

[Paul B.]

Correct me if I'm wrong but isn't that rifle a single shot? If so, there is no reason to worry about crimp and you can seat that bullet wherever you get the best accuracy. It's not like you have a magazine full of cartridges bouncing around back and forth driving the bullets deeper into the case. Forget about that cannelure.

FWIW, I hunt and shoot with single shot rifles, mostly Ruger #1s ranging in calibers from .22 Hornet to .416 Rigby. I reload for all of them and never use a crimp. What's even more interesting, that same uncrimped ammo works just fine in my bolt and lever action rifles. It's never given my any problem.

Give that ammo without a crimp in that rifle. I think you'll ending up enjoying iy just fine.
Paul B.

[deerslayer303]

Thank you Paul for the Reply. Yeah, its a single shot rifle. I didn't even realize I didn't need a crimp. I just thought a crimp was important to help build pressure. I sure will try a string with these bullets seated to 2.635 with no crimp.

[std7mag]

I don't crimp my bottle necked cartridges either, and all my rifles are bolt action.

One thing to check, is if they actually ARE 80gr!

And SAAMI lengths for 243 Win are Max length, not Min length.

[deerslayer303]

Thanks std7mag,
They are indeed 80 grain and measure .243" at the base of the bullet. The Lee manual give a Min for that bullet of 2.635 and a Max of 2.710.

[44 AMP]

The Lee manual give a Min for that bullet of 2.635 and a Max of 2.710.

The industry standard max COAL length for the .243 Win is 2.710"

Min length is irrelevant. AND, since you don't know who's bullets they are, why do you think LEE's min length even matters???

Min length is an arbitrary point, chosen so it will feed through the action of most repeaters. Max length is the same, and also to keep the bullet out of the rifling as well. If you're using a single shot, min length doesn't matter, and max length is anything short of touching the rifling.

And, crimp is not needed, in a .243 with the powders you have.

[Rimfire5]

Of the powders you listed, the Hornady manual says that IMR 4064 "performed very well".
44 AMP is right on.
But I would caution you about decreasing the COAL too much if you intend to load very close to Pmax because every 0.002 decrease in COAL increases the velocity by 1 fps and also increases the chamber pressure by about 40 psi because you are decreasing the volume between the powder and the base of the bullet.

[ammo.crafter]

4064 is a fine powder for the 243 + 80gr bullets.

I use it in my custom Mauser 6mm with 75gr bullets.

[44 AMP]

But I would caution you about decreasing the COAL too much if you intend to load very close to Pmax because every 0.002 decrease in COAL increases the velocity by 1 fps and also increases the chamber pressure by about 40 psi because you are decreasing the volume between the powder and the base of the bullet.

While this is a possibility, I would point out that is doesn't necessarily apply to every load possible.

If the load you are using does not fill the powder space completely, seating the bullet slightly deeper doesn't automatically result in increased velocity or pressure. It can, but it might not, it depends on several other variables.

[Rimfire5]

44 AMP

QuickLOAD would disagree regardless of the volume available, but I did say caution if he was loading close to Pmax.
Pretty hard to have a load with IMR 4064 close to Pmax that is not filling the cartridge nearly full.

[deerslayer303]

Min length is irrelevant. AND, since you don't know who's bullets they are, why do you think LEE's min length even matters???

The Lee Manual doesn't list Brands of Bullets, all they list is the weight and type of a bullet, I.E. "80 grain Jacketed Bullet" And it does List a MIN COAL for each one. That's what confused me. Unlike my Hornady manual it lists Data for every bullet they make.
But Thank you all for posting. I understand what ya'll are saying. I just like to make sure and ask others when an issue like this comes up. I like my face and would like to keep it intact. Being this is a Single Shot I have a little more room to move the bullet around. I was thinking of taking a sized case and just start a bullet in the case mouth, then chamber and close the breech. The start of the rifling should seat the bullet to the length where it would just touch the rifling. Then measure and seat my bullets to that depth? I'm sure there is a more scientific method to doing this.

[44 AMP]

I was thinking of taking a sized case and just start a bullet in the case mouth, then chamber and close the breech.

you don't want to do that, that way, because it won't get you what you're looking for.

Not with a sized case. Because the sized neck will resist the bullet moving back into the case when it hits the rifling, and the force needed to seat the case in the chamber and close the action may leave the bullet jammed into the rifling when you pull the case out. No length reading there...

What you want to use is a fired case that fits the chamber, THEN either just kiss the case mouth with sizer or even use the crimp shoulder in the seater die, the object is to put just enough tension on the case mouth so it holds the bullet snugly enough it won't fall out, but can still be moved with light pressure, and stay where it gets pushed to as you remove and measure it.

Alternately a fired case and a wrap or two of tape on the bullet to give it a snug fit but not so tight that it gets stuck in the rifling.

I have also seen a fired case with the neck slit, then sized the point is to hold the bullet firmly enough so it doesn't slide on its own, but not so hard it won't move when you push it into the rifling.

Once you get that OAL measurement, you can begin to play with how far off the lands gives you best results. For that bullet. A different bullet requires its own measurement, to be safe and certain.

[deerslayer303]

Awesome info Sir, thank you very much.

Sent from my E6910 using Tapatalk

[akinswi]

44amp is correct,

another way I have done is seated the bullet as normal then I pulled the bullet from the case neck, you still have some resistance but is not as tight as when you first seated the bullet, because you expanded the case neck some when you originally seated, but its not expanded as such from firing. you then should be able to start it in the case neck again then measure.