CIP VS SAAMI for 6.5X55 SE what do you load?

[Tommy_Fontaine]

Hi folks,

Just got back from the range with some chrono measurements from my 6.5X55 SE Tikka T3x. Handloaded some PPU brass, with 48.5gr Hodgdon Super Performance, CCI #200, and some Speer 140gr Spitzer for a whopping mean of 2828fps and STD-DEV of 20. It shot nice less than MOA, and no pressure signs. So my question to you is do you stick to the US SAAMI specs (51,000psi) or Euro CIP (54,110) or beyond? BTW if anyone got Quickload please run this data for the estimated pressure I'm curious.

Cheers,
Tommy

 

[375 Ruger Fan]

Very interesting. I just acquired a used Ruger in 6.5x55 and have played with some loads using Winchester Staball 6.5. I have gone a few grains over max book load and still no signs of pressure, but velocity is in the 2600 fps from a 22 inch barrel.

Your load with 48.5 grs of Superformance is about 5.9 grains over max book load (Hornady 10th Ed)

Western Powder table lists Pressure in psi, but can't tell if it is CUP or SAMMI

Hodgdon lists pressure as CUP, but doesn't list Superformance

 

[shootist~]

CIP and SAAMI pressures are measured at different places (CIP near the case mouth). Don't assume higher CIP numbers are related to SAAMI maximum powder charges.

IMO, you need to find load data specific to the "SE" chamber.

 

[Desperatezulu]

Hi folks,

Just got back from the range with some chrono measurements from my 6.5X55 SE Tikka T3x. Handloaded some PPU brass, with 48.5gr Hodgdon Super Performance, CCI #200, and some Speer 140gr Spitzer for a whopping mean of 2828fps and STD-DEV of 20. It shot nice less than MOA, and no pressure signs. So my question to you is do you stick to the US SAAMI specs (51,000psi) or Euro CIP (54,110) or beyond? BTW if anyone got Quickload please run this data for the estimated pressure I'm curious.

Cheers,
Tommy

Hi Tommy,

Ran your data through GRT - to calculate properly, we really need more specifics like barrel length, case capacity, OAL etc.

Running the powder charge and MV and using the default specs for the Swede suggests you're running around 57k psi, which is a bit over Pmax. This shouldn't be an issue for a modern rifle like the Tikka.
Your MV is also on an accuracy node, so good accuracy is to be expected.

I also run a Swede firing 140gr Accubonds and BTs at similar velocities out of a 24" barrel with no pressure issues.

 

[Shootist43]

IMHO everyone should totally disregard SAMMI loads for use in a modern 6.5 X 55. Even the 1896 Swedish Mausers were proofed at slightly more than 64,000 PSI. Your current load is just fine. I just opened up QL, it doesn't support Hornady Superformance Powder.

 

[Bob Nelson 35Whelen]

Very interesting. I just acquired a used Ruger in 6.5x55 and have played with some loads using Winchester Staball 6.5. I have gone a few grains over max book load and still no signs of pressure, but velocity is in the 2600 fps from a 22 inch barrel.

Your load with 48.5 grs of Superformance is about 5.9 grains over max book load (Hornady 10th Ed)

Western Powder table lists Pressure in psi, but can't tell if it is CUP or SAMMI

View attachment 465631


Hodgdon lists pressure as CUP, but doesn't list Superformance

View attachment 465632

@375 Ruger Fan
Hornady 10th edition gives very few loads for superformance and those that it does list are usually for lighter bullets in the caliber.
This is strange to me as all the burn rate charts I have checked lists superformance as being a bit slower than 4831sc and Re22. After much research I decided to use it in my 25 with 100gn and 115/117grain. I loaded it to the same charge as I use for 4831sc ( working up from a few grains below). The results were between 150fps to 250fps plus higher velocities with what appeared to be less pressure.
Just my personal experience with the superformance powder.
Bob

 

[Tommy_Fontaine]

Thanks for the information guys! I was figuring I was around 56K to 59K psi based on my extrapolations.

 

[francois_458]

Hi, I'm new to this cartridge and just recieved my howa 1500 in 6.5x55. i started with some factory loads just get a bunch of rounds through the barrel and to get a hold of brass. Im now looking beginning the process of reloading. The powder i would use is Somchem S365 as I have a lot of it that I use for other calibres. My question is how hot of a charge is safe using this powder? I would like to end up at right around 2650 - 2700fps out of my 22 inch barrel using the 140 nosler bt

 

[Desperatezulu]

Hi Francois - I have used S365 extensively in this calibre and use BTs too. You can get into that velocity band but you will be close to the red line - and S365 is notoriously inconsistent from lot to lot, so develop the loads carefully.

What brass are you using - the internal volume of that brass will play a role too.

I use 45.0gr of S365 lot 89, which is right on the limit. The Swede does have quite a low pressure redline at 55k psi, so I am ok using this. Use this info at your own risk and build up in steps, measuring velocity as you go.

 

[francois_458]

Hi Francois - I have used S365 extensively in this calibre and use BTs too. You can get into that velocity band but you will be close to the red line - and S365 is notoriously inconsistent from lot to lot, so develop the loads carefully.

What brass are you using - the internal volume of that brass will play a role too.

I use 45.0gr of S365 lot 89, which is right on the limit. The Swede does have quite a low pressure redline at 55k psi, so I am ok using this. Use this info at your own risk and build up in steps, measuring velocity as you go.

Hi. I am currently using ppu brass. I plan on starting at around 43 grains and working up from there. The brass has an average capacity of 58.3 grains h2o

 

[francois_458]

I also wonder if it could be possible to exceed those pressures at all with a more stable powder like VV or Imr... I see a lot of loads that in theory should be producing close 60k psi
Is this potentially possible?
Not that I need the velocity that comes with thkse pressures currently, but maybe for future forays into long range matches

 

[Frederik]

Francois, I shoot 140gr S&B spitzers out of my Swede at 2730fps with a 23" barrel its on the max but no pressure signs.

So it's possible to get around 2700 fps but like Desperatezulu mentioned check yor burn rate on the S365 first. I'm also on 45gr of Powder.

 

[leslie hetrick]

i,m running N-560 and 140gr fb sp at 2800+ fps in a cz 550 rifle.

 

[shark_za]

I'm working a load right now using S365 and a 140gr bullet, I'm getting 2570fps with 43.4 and I ran out of steps on my "ladder" and have to return once I load a few more steps up to get nearer 2700fps.
Somchem list 42.5gr as max getting around 2600fps , my rifle is very different it seems. I have not even seated them far out like my Tikka allows.

 

[francois_458]

I'm working a load right now using S365 and a 140gr bullet, I'm getting 2570fps with 43.4 and I ran out of steps on my "ladder" and have to return once I load a few more steps up to get nearer 2700fps.
Somchem list 42.5gr as max getting around 2600fps , my rifle is very different it seems. I have not even seated them far out like my Tikka allows.

This is interesting, I'm about ready to start developing a load and testing, just waiting on a new tumbler so I can get my brass clean

 

[375 Ruger Fan]

I kept testing increased loads with my Ruger M77 MkII, slowly working up and not seeing any pressure signs. Very happy with the results in my 22 inch barrel Swede, using 47.6 grs to achieve 2780 fps with a 140 gr SST. Velocity data is from a Magneto Speed.

 

[francois_458]

ok, so I've been shooting my 6.5 a bit now with ppu 139gn factory ammo. this runs around 2400fps through my 22" barrel... groups are ok for factory, just under 1" @100m.
my big concern is that almost every single case has ejector marks on it and I can see where they have been 'shaved' by the bolt face. the primers show no pressure signs at all.
any ideas as to what's up?

 

[francois_458]

here are some images of random pieces i took from my box of cases. some of the cases have no marks at all, but the majority of them have these marks

 

[Frederik]

Francois, I don't think you shoukd worry about it much as its factory ammo and its not running fast either.

 

[francois_458]

Would these cases be safe to reload with?
Eventually i will be looking at lapua or norma cases, but this is what I have for now