Favorite 6mm?

[Art30/30]

How would you like THAT job? Stamping primers! Haha (I know…. Bad joke)

 

[lysanderxiii]

Ever wonder why .243 Winchester is 0.030" longer than the 308 Winchester?

In the middle of 1952 the Army contracted Winchester to developed three homologous cartridges based on the FAT1E3 (.308 Win) cartridge case, one in .27 caliber, one in .25 caliber and one in .22 caliber. These were to be accompanied by 20 Winchester Model 70s chambered in the experimental cartridges, as well as two in .30 caliber (T65). Because of the desire to have the cases as close to exactly the same the FAT1E3 case was lengthened so the case with the longest shoulder (the .22) would still have enough neck length to adequately hold the projectile.

The .27 caliber round fired a 102 grain steel core bullet at 3,220 fps. The .25 caliber round fired a 81 grain steel core bullet at 3,550 fps. The .22 caliber fired a 54 grain steel core bullet at 3950 fps. The .27 and .25 caliber rifles were 1 turn in 36 calibers, the .22 was found to work best with a 1 turn in 44 calibers even though the Army specified 1-in-36. Winchester did some of their own development work and felt that with lead cored projectiles, a 6mm could use all three bullet weight at approximately the same velocities, and would combine the best attributes of all three.

Coincidentally, all work was complete and the final report from Winchester on the homologous cartridge program was delivered in June 1954.

 

[Litetrigger]

A couple of 6mm's are this .243 Win and 6mm CHeetah. The rifle at top is/was a Remington M-700 BDL Varmint in what was originaly a .243 and now a 6mm CHeetah by rechambering barrel. Scope is a 10X Lyman All-American. Lower rifle is a vintage SAKO varmint model in standard .243, scope is vintage (1970's) 20X Redfield 3200. The CHeetah is a .243 Win. case blown out to sharper shoulder and shortened neck for increased capacity. Like it's speedy forerunner .224 CHeetah, the 6mm version has proven exceptionally accurate.

 

[Nature Boy]

@Litetrigger

I continue to be dumbfounded by the quality of your collection and your historical knowledge. I’ve run out of adjectives a long time ago.

 

[1948CJ2A]

@Litetrigger

Wow! That Redfield scope on that Sako rifle is something else. Vintage, application specific, and cool. Thanks for sharing.

 

[tark]

Thank you Mr. Tark for mentioning the .244 H&H, it's an interesting cartridge. I've never seen a rifle is this caliber and can't remember how I came to have the sample shown in pic. I expect very few rifles and ammo were made. Another British 6mm cartridge is the H&H .240. I've hunted deer in Scotland with a .240, with a pretty Holland &Holland rifle they had loaned me in hopes I would buy it. Which I didn't. The 240 ammo I hunted with had a Norma stamp on primer so I assumed they made the whole catridge.. It is quite similar to the .240 Weatherby Mag and I suspect it gave Roy Weatherby the inspiration for his 6mm Mag, even borrowing the name. Guessing, but Norma may have also made the .244 H&H, as the sample I have has a steel jacketed bullet like Norma once made. Attached is a comparison pic of the two British 6mm, note Norma stamp on primer of .240.View attachment 1189554View attachment 1189555View attachment 1189556

Nice Pic, but you failed to mention that the 244 H&H is the larger cartridge.