What to do when load data just doesn't exist?

[Dioxin]

I've an Accuracy International rifle in 7.5 x55 Swiss, which I intend to use initially for punching paper/steel at long range.
The issue that I have is that load data is non existent.
I'm using Sierra Matchking 190 grains with Reload Swiss RS62 powder, and RWS 5620 Berdan Primers.
Reload Swiss give data for 175 grain Matchkings and 180 grain Norma HMK
Matchking has a powder range of 47-52 grains
Norma HMK has a powder range of 42-46 grains

I took the heavy bullet data as a base and at each .4 grain interval I made 5 rounds.
Carefully fired them, checking for pressure signs after every firing, none seen.

As I'm trying to extend my range as much as possible, I'd like the highest safe velocity, then tune downwards from there to find an accurate load.

Is the correct approach to continue .4 grain increments until I see pressure signs then use the powder charge below that as my powder/bullet combination max charge?

Let me know if you need more info.

 

[918v]

Look at a similar capacity cartridge like .30-06

 

[Dioxin]

I did try this, but again no data for 190 grain hpbt.

Earlier today I had emailed Reload Swiss, they were exceptionally helpful and provided an output from QuickLoad for my rifle, bullet and powder.
Must say I'm impressed with their response and also the application used.

I'll have to get a copy!
Regards
Dio

 

[ShtrRdy]

Maybe see if someone with the Quickload program can run a simulation for that combination.

 

[gohring3006]

Did you call Sierra? They may have the Data, if so they will email it to you...

 

[Mikecr]

maybe see if someone with the quickload program can run a simulation for that combination.

wrong

must say i'm impressed with their response and also the application used.
I'll have to get a copy!

right

 

[Dioxin]

well its all the same QuickLoad program, ReloadSwiss publish their powder data in QuickLoad format.

They just specified my rifle/powder/bullet combo and sent me the data.
They also sent me the data for another of their powders which has similar performance.

I'll have to admit my noobish nature, I wasnt aware such programs existed, nor that companies would be so helpful.

(Buying firearms in Switzerland is full of pitfalls if you dont speak the language)

Regards

Dio

 

[red dawg]

Hey Dioxin, there is 3 loads for 7.5 + 55 using rl 15 and rl19 all by the same guy on reloaders nest For what it's worth

 

[BergerBoy]

I've an Accuracy International rifle in 7.5 x55 Swiss, which I intend to use initially for punching paper/steel at long range.
The issue that I have is that load data is non existent.
I'm using Sierra Matchking 190 grains with Reload Swiss RS62 powder, and RWS 5620 Berdan Primers.
Reload Swiss give data for 175 grain Matchkings and 180 grain Norma HMK
Matchking has a powder range of 47-52 grains
Norma HMK has a powder range of 42-46 grains

I took the heavy bullet data as a base and at each .4 grain interval I made 5 rounds.
Carefully fired them, checking for pressure signs after every firing, none seen.

As I'm trying to extend my range as much as possible, I'd like the highest safe velocity, then tune downwards from there to find an accurate load.

Is the correct approach to continue .4 grain increments until I see pressure signs then use the powder charge below that as my powder/bullet combination max charge?

Let me know if you need more info.

Forgive me for sounding like a complete idiot but I just did some comparisons and started low but came up and made my own load data. For example if.... I couldn't find load data on the 215s bc at one time there was not much out there but I saw the 210s or 200 load data I would just use common sense and as safe as possible guess what would work.
There is no easy way and you probably have a long road ahead of you.

 

[Trickymissfit]

Hodgdon has it listed in their manual. The heaviest bullet they list is 180 grains.
gary

 

[Sargesniper]

I've an Accuracy International rifle in 7.5 x55 Swiss, which I intend to use initially for punching paper/steel at long range.
The issue that I have is that load data is non existent.
I'm using Sierra Matchking 190 grains with Reload Swiss RS62 powder, and RWS 5620 Berdan Primers.
Reload Swiss give data for 175 grain Matchkings and 180 grain Norma HMK
Matchking has a powder range of 47-52 grains
Norma HMK has a powder range of 42-46 grains

I took the heavy bullet data as a base and at each .4 grain interval I made 5 rounds.
Carefully fired them, checking for pressure signs after every firing, none seen.

As I'm trying to extend my range as much as possible, I'd like the highest safe velocity, then tune downwards from there to find an accurate load.

Is the correct approach to continue .4 grain increments until I see pressure signs then use the powder charge below that as my powder/bullet combination max charge?

Let me know if you need more info.

Cartridges Of The World has loads listed for it. Bullet Weights are---130---150---165---180--and 200 gr. 308 bullets. Listed on page #216==7.5x55 Swiss Schmidt Rubin. Is this your cartridge?

It shows 4 smokeless powders used.===3031===4895===4064===4350. They only list one charge weight for each of the powders. I assume this is max. load for the named bullet It appears that there are two bore diameters like the German Mausers of that time period.

 

[918v]

There is not going to be much difference between 180 and 190gr bullets.

 

[Mike 338]

I've an Accuracy International rifle in 7.5 x55 Swiss, which I intend to use initially for punching paper/steel at long range.
The issue that I have is that load data is non existent.
I'm using Sierra Matchking 190 grains with Reload Swiss RS62 powder, and RWS 5620 Berdan Primers.
Reload Swiss give data for 175 grain Matchkings and 180 grain Norma HMK
Matchking has a powder range of 47-52 grains
Norma HMK has a powder range of 42-46 grains

I took the heavy bullet data as a base and at each .4 grain interval I made 5 rounds.
Carefully fired them, checking for pressure signs after every firing, none seen.

As I'm trying to extend my range as much as possible, I'd like the highest safe velocity, then tune downwards from there to find an accurate load.

Is the correct approach to continue .4 grain increments until I see pressure signs then use the powder charge below that as my powder/bullet combination max charge?

Let me know if you need more info.

Not that uncommon for published load data not to exist. Gotta start with the closest published load data you can compare and start way low and work your way up, keeping a close eye for signs of pressure and anticipated speed of bullet. If your getting speeds that are just way to high, even without signs of pressure, your probably flirting with danger, so stop. That's your load data for that particular rifle.

 

[Deleted member 46119]

Read this Real Guns - The Swiss K31 Part 2

I have not loaded for my Swiss yet.

I am willing to run a QL model for you.