6.5 PRC Improved Medium Action Build

[MBanning]

I have been gathering parts for a new rifle. Zermatt Arms TL3 medium length, Manners PRS1 with Hawkins medium bottom metal, Triggertech Diamond, Nightforce ATACR in a Spuhr mount.
I have 2 Proof barrel blanks, a comp contour ss as well as a heavy sendero carbon fiber. I am looking for a reamer to get these chambered. My plan is to shoot Berger 156s. If I was smart I would just go PRC but that's no fun. I would really like to blow the shoulders out to 40° for an improved version. I have been keeping an eye on the 6.5 PRC Primal that Primal Rights is working on but have not heard back yet on reamer and his custom SAC die availability. I have also been looking into the 6.5 PRC/SI (Sherman Improved), it seems to be the same thing as far as I can tell. One downside I see is the Sherman Wildcat sizing dies all use neck bushings. I have used several and never found the necks to be as concentric as I would like. I much prefer a solid, one piece die. I suppose I could get a custom die from Whidden. Has anyone gone that route for custom dies? Please share your experince.
Does anyone have a 6.5 PRC Improved or any comments on these 2 options?
Thanks for reading and any input you can provide, MBanning

 

[Chickentoast]

Why not just go SAUM? I have 2 Sherman Max barrels (SAUM imp) and shoot the 153.5's as well as the Badlands 135 solids. 153.5's run ~3125 in my high node. Reg SAUM should still run ~3K+ with the big Bergers.

 

[MBanning]

Why not just go SAUM? I have 2 Sherman Max barrels (SAUM imp) and shoot the 153.5's as well as the Badlands 135 solids. 153.5's run ~3125 in my high node. Reg SAUM should still run ~3K+ with the big Bergers.

Really it's just because I want to use Lapua brass. You make a good point though.

 

[Surdez1994]

I would go the 6.5 prc/si route.

Just got my 6 prc/si reamer from Rich last month. I went the exactsame route solely for the lapua brass

 

[MBanning]

Nice. Did you get a barrel spun up yet? Pick out a sizing die?

 

[Chickentoast]

Didn't realize Lapua embraced 6.5 prc already. Lapua made SAUM brass too, but none was available when I was looking - unsure if available now. I run ADG, which go 4-6 firings on my high node after fire-forming with 145's around 2850.

 

[Surdez1994]

Nice. Did you get a barrel spun up yet? Pick out a sizing die?

Im using his 6.5 prc/si dies. As i will just use the proper bushing. Sent the reamer and all my parts to Kinport Peak rifles beginning of the month, no data yet

 

[4O6shootist]

I'm quite certain Lapua prc brass isn't made by lapua. The fonts are different, and internal tooling marks look the same as........Peterson!🫨 I tested lapua VS adg in 65 and 300prc, adg held less powder and never gave pressure signs till bout 100fps more than lapua, it's not any better that I'd make a cartridge choice . Going 40° and 0.0065/" taper gives the 65 prc 70-71gr capacity. The 65 Saum holds 72gr. Realistically that extra 2gr capacity you found now gives you any extra 20-25fps at the same pressure as a standard 65prc. All the extra "efficiency" Rich claims, is just really high chamber pressure. This is also coming from a guy who's built 65 max, 7 max and a 25sst. It's all kool-aid and snake oil. You're not gaining enough capacity to make any meaningful velocitiy gains at normal pressures, it just lets you run chamber psi north of 80k psi due to the square case walls.