.243 Chamber Specs

Value priced adult & youth top break handguns, rifles, & shotguns chambered for centerfire & rimfire cartridges as well as shotshells. These arms are offered as single chamberings as well as a Matched Pair, Pick Four combinations, Trifecta, & the Wizard.
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klr
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.243 Chamber Specs

Post by klr »

It looks like the single shots are about dead, but I thought I'd put this out there in the event someone is struggling with accuracy in the future and turns to this forum for help.

In a nutshell, the chamber on my 243 single shot has a huge freebore. I tested for accuracy and was underwhelmed so I did an impact cast of the chamber. I found a .2495" dia x .250" freebore before the rifling starts. Even 105gr bullets seated as far out as possible don't come close to touching the lands.

This may not be the reason for poor accuracy, but I can't imagine a .243 dia bullet rattling in a .2495 dia hole can be good for it.
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Re: .243 Chamber Specs

Post by Ranch Dog »

Yeah, that's not good at all. I wonder why they would do that? They probably don't know.
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Re: .243 Chamber Specs

Post by Ohio3Wheels »

Interesting, i haven't done a lot of shooting with my 243 Wizard barrel but it seemed to hold some 90 grain PPU rounds into about an inch for 5. I'm not so sure that some of the size isn't me I have a hard tme getting on the scope. Not the easiest rifle to mount is the Wizard.

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klr
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Re: .243 Chamber Specs

Post by klr »

Update:

Disclaimer: I bought this rifle for a barrel stubbing project. I have a .243 and don't want another. I don't care if I trash this barrel if I learn something along the way.


So:

I chopped the barrel to 16.5" just to see if it made any difference in accuracy. I did a half-fast job on squaring the muzzle and used a carriage bolt to crown it.

I shot a quick 3-shot group. - 0.5'" at 55 yds. Yea, not enough to be conclusive but it was spraying them before and I couldn't even get two close together before.

I didn't figure the shorter barrel would make that much difference so I got a magnifying glass and looked at the original muzzle. One side was rounded off and the other had a small burr extending into the bore.

I shot a few more rounds over the chrono using different powders and bullet weights just to see how much velocity I could get out of a 16" barrel. Compared to my 22" Remington 7600, I lost about 350 fps.

Muzzle blast wasn't as bad as I thought. I guess because it's already loud to start with.

I still haven't had a misfire. I trimmed the hammer nose to give .046" FP protrusion before I even started.

I think it's going to make a nice cheap 357 Maximum rifle.
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Re: .243 Chamber Specs

Post by Ranch Dog »

klr wrote:I didn't figure the shorter barrel would make that much difference so I got a magnifying glass and looked at the original muzzle. One side was rounded off and the other had a small burr extending into the bore.
A buggered up muzzle would do it and a good reminder to check this kind of thing when the rest of it doesn't work out. Keep up posted on your project!
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Re: .243 Chamber Specs

Post by GasGuzzler »

Interested.
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Re: .243 Chamber Specs

Post by jeepmann1 »

Might ream it to a 6mm Ack it is long enough to clean up the excessive freebore and will not require any ejector rework
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Re: .243 Chamber Specs

Post by klr »

jeepmann1 wrote:Might ream it to a 6mm Ack it is long enough to clean up the excessive freebore and will not require any ejector rework
George
That would work, but I have no desire for another 6mm round, especially since the short barrel gives up so much velocity.

...and 357 Mag & Max are legal for Ohio deer hunting, I have a 357 barrel and all the reloading/casting equipment for that cartridge.
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