A labor intensive 6.5mm that really screams???

[goodgrouper]

I thought some of you would like to know what I held in my hands this afternoon. A gunsmith in Idaho showed me a 6.5 that just might be worth the effort of case forming. It was called a 6.5 lrt (his initials). It was a 25 wssm necked up and the shoulder was blown forward a bit and given a 45 degree angle. It was tight necked and throughted for the 142 MK. He said his charge was 49 grains of RL22 and it was 105% density. He also claimed that he just finished chronographing it and it was shooting the 142 grain bullet at 3050 with just a 26" barrel! This load produced a standard deviation of 7, and shot a .5 inch group at 200 yards. I thought it sounded pretty efficient because my 6.5-.284 pushes the same bullet with the same charge at 3100, but it has a 30" barrel. This short fat thing might actually be working like they say it does!

 

[dreal]

Interesting approach starting with a 25 wssm. I am in process of building a 6.5 SAUM for the 142 SMK. It will be a 26" Jeff Lawrence #4 barrel on a Remington Short Action and McMillan Stock. The rifle started life as a .300SAUM but I just haven't been impressed with the performance of the .30 cal. so I thought I'd give the 6.5 a try. I'll post again when I have some real news report about how this short fat one performs.

 

[Guest]

If he is getting that sort of velocity out of that short of a barrel he must be getting some pretty high pressure , I've heard of a few guys shooting the WSSM's and getting into pressure trouble realy quick , like not seeing any signs to getting realy sticky bolt lift with just a half grain increase in powder.
I believe that their is a limit as to how effecient you can make a case safely

 

[Mikecr]

Matched in QuickLoad shows 67.5Kpsi(65K SAAMI Max).
So it's a hot load. But given that it works for him, I'd say it's fine provided he doesn't get his ammo out in the sun. He'd have 3140fps with a 30" barrel.

With a 26" barrel he could get 3100fps @ 57Kpsi(10K less) if he used Lapua 123gr and VVN560/IMR4350/Norma204 ~same load density and same seating. That way his barrel, and possibly his life, might last alot longer.