6mm mach IV rifle

[steevo]

I received this rifle from a family member who didn't shoot it much, its a Remington 700 in 6mm mach IV. it has a 28" stainless pac nor barrel installed on it, he doesn't remember much on the rifle cartridge itself as he is getting old. only thing I know is it has roughly 200 rounds through it from the records he kept on the loads.

ive searched on here and didn't find much on this round and seems to be you have to make your own brass for it.

if anyone on here knows about this cartridge and could fill me in a little on what is needed to make the brass and reload for this or am I better off rebarreling the rifle to a more normal caliber ( coyotes).

thanks in advance on any info,
steevo

 

[Nimrod]

The 6mm Mach IV case is made by necking down and fireforming 7mm Remington Magnum brass. IIRC there was a write up in the November 95 Guns and Ammo but I could be off in left field about that. I flirted very briefly with one back in '96 or thereabouts, rough on throats best I recall.

 

[steevo]

yeah that's all I have found as well, even tried searching if there is any other caliber to have the barrel reamed to and came up empty......

looks like I may just have to send it out and get it rebarreled.......doesn't look like anything can be done with this caliber unless I start making cases

 

[Deleted member 8840]

I have 2 Mach IVs Send me a email and I'll give you some info.

 

[Max Heat]

I'm considering either a 6 or 6.5 for my next build. I love the mach IV name, and what it implies - that it slings lead at [almost] 4400fps. Is this true, or deceptive "labeling"?

If true, I AM impressed. But the apparent sheer obscurity of the cartridege looks like it will keep the 6M4 out of the running, for me.

 

[AZShooter]

The 6.5mm Mach IV IS the 264 win mag. It is a SAMMI adopted cartridge and has been since 1959.


The 6mm-264 really isn't obscure just a bit crazy. It is the natural progression for a typical rifle looney that loves to neck cases up and down. The task of doing so is the easiest way to make a wildct.

When many cartridge designs were unveiled the gun nuts had to neck it up and down.

Happened with the 30-06, 308, 7 x 57, 284 win, and more recently the 375 Ruger. Heck the 375 Ruger is pretty much the Dakota reincarnated with a smaller rim diameter.

Many of the early wildcats have become standard cartridges and it is still happening today.

When Winchester came out with the 264 win mag, 338 win mag and 458 win mag at the same time in 1959 that case was immediately made into a 308 and 7 mm. The folks got fooled when Winchester later came out with the 300 win mag and it wasn't a necked up 264 or necked down 338 win mag. That 30 cal version is still called the 30-338 win mag. It is shorter than the 300 win mag with a longer neck. It is very similar to the 308 Norma mag.

It took Remington to make the 7 Rem mag and it sure wasn't what Warren Page championed in the 7mm Mashburn.

When the 300 WSM came out it immediately became a 6.5 and a 338
And there was some necking up and down for the WSSM cases.

I think you get the idea. pretty normal stuff, just more costly. I must admit I get swept up with the fever and I KNOW performance wise that I am not going to create anything that hasn't been made before but it sure is fun!

 

[MudRunner2005]

Yep, 7mm STW became a standardized SAAMI caliber, and it was originally a wildcat formed by necking-down 8mm RemMag brass.

The 7mm RemMag also was a wildcat formed from the .264 WinMag case. The unfortunate side-effect of doing so, resulted in a sharp decline in sales and popularity for the .264 WinMag after Remington introduced the new 7mm RemMag caliber along with it's new Model 700 rifle in 1962. Alot of folks didn't realize that the 7mm RemMag derrived from the .264 WinMag. Cool little fact.