Rechamber 243 to 6mm Rem because I'm odd

[hifiwasabi]

An idea (of questionable feasibility) has been rolling around in my head. Can a .243 be simply rechambered in 6mm Rem, or is there other fitting and machining steps that need to be done? I understand that the Mauser case may not operate well in the standard short action, would one be better to find a longer action and go that route, or would the standard short action work with typical 100 grain bullets? To add complexity to weirdness, I'm left eye dominant and require the use of a left hand action. If I had the funds, I'd build a full custom 6mm Rem left hand as well as a great many other things, so keep budget in mind.

 

[dan belisle]

I have a friend who did this (twice) to outfit his twin boys with a 6 Rem. Rechamber, check headspace. Adjust if required, polish, and start shooting. 6 Rem is a better cartridge in my point of view, but there's not a lot of difference. Still, I've owned 3 of them, and I keep sending 243's down the road, or disassembled for the action. - dan

 

[Buckmastr]

You get better brass with a 243 win compared to 6mm Rem. You can push it harder if you like too.

 

[remington jim]

I own BOTH 243 Win and 6 mm Rem NOT much performance difference between the 2 - and Not WORT $$ rechambering a good 243 - that's for SURE ! jmo RJ

 

[FLHTCUI]

I own BOTH 243 Win and 6 mm Rem NOT much performance difference between the 2 - and Not WORT $$ rechambering a good 243 - that's for SURE ! jmo RJ

He could just buy the .240 Weatherby, no ?
Rob

 

[tiriaq]

Will a 6mm reamer cleanup a .243 chamber completely? Or will the barrel have to be set back a bit?

 

[hifiwasabi]

I have been unable to find a left hand 240 Weatherby. I'm trying to find out if the barrel would need to be set back also.

 

[dan belisle]

I own BOTH 243 Win and 6 mm Rem NOT much performance difference between the 2 - and Not WORT $$ rechambering a good 243 - that's for SURE ! jmo RJ

100 fps for most bullets. And a longer neck, which some reloaders appreciate. 240 Wby is basically a 30-06 case with a belt if I remember correctly. - dan

 

[357Maximum]

I was informed by a person who has put together many rifles that a 6mm reamer will not clean up the shoulder area of a 243 chamber, the barrel would have to be set back.

 

[G.E.FLACH]

In order to do it you need to remove the majority if not all of the 243 chamber.You would need a pretty long shank to do that.

 

[Rembo]

I've done it on a couple Rem 700 243 Varmint barrels. I take the factory thread right off.

 

[dan belisle]

I've done it on a couple Rem 700 243 Varmint barrels. I take the factory thread right off.

Thats good advice, i think. - dan

 

[remington jim]

100 fps for most bullets. And a longer neck, which some reloaders appreciate. 240 Wby is basically a 30-06 case with a belt if I remember correctly. - dan

Yea it is and it really kicks the #### out of a 243 of. a. 6mm Rem ! RJ

 

[nowarningshot]

I own BOTH 243 Win and 6 mm Rem NOT much performance difference between the 2 - and Not WORT $$ rechambering a good 243 - that's for SURE ! jmo RJ

I know the 7x57 (parent case of 6mm) and 7-08 (same case as 243) are only a gr apart in case capacity, x57 being bigger.

 

[guntech]

I was informed by a person who has put together many rifles that a 6mm reamer will not clean up the shoulder area of a 243 chamber, the barrel would have to be set back.

This is true. A 6mm Ackley would clean up the .243 chamber but the standard 6mm Rem would require barrel set back.

 

[hifiwasabi]

I gotcha. So maybe just save and do a .240 Wby or live with the .243.

 

[guntech]

I gotcha. So maybe just save and do a .240 Wby or live with the .243.

What action is this 243 on? That will make a difference on what you can do. A Remington short action is really too short for a 6mm Rem if you want to seat the bullets where they should be seated. That action is better left as a .243...

 

[hifiwasabi]

I am in the market for one, so am open. Seems like T3's, Ruger Americans and X bolts are the most readily available.

 

[remington jim]

Yes , ! RJ

 

[StoneHorse]

A 6mm Ackley would clean up the .243 chamber but the standard 6mm Rem would require barrel set back.

Noted, thanks guntech.