300blk loading

[alexs2006]

So I’m prepping to load some 125gr matchkings. Looking at data from Sierra and hornady the data is way off. Using WW296 powder.

Sierra says max load is 20gr and will net 2300fps.

Hornady says max charge is 17.5gr and will net 2000fps.


What to do?

 

[Please Delete]

Hodgdon is right in the middle..

is it 300bo brass or converted 300bo brass? 52.5k psi doesn't seem max...I wonder how much 296 you can fit in the case.

 

[Please Delete]

So I’m prepping to load some 125gr matchkings. Looking at data from Sierra and hornady the data is way off. Using WW296 powder.

Sierra says max load is 20gr and will net 2300fps.

Hornady says max charge is 17.5gr and will net 2000fps.


What to do?

IFIN it were me...I'd start at 17grains and work up till it is a compressed load...staying under the 20 grains Sierra says. are the 125gr matchkings flat base?

 

[alexs2006]

Hodgdon is right in the middle..

View attachment 8309528

is it 300bo brass or converted 300bo brass? 52.5k psi doesn't seem max...I wonder how much 296 you can fit in the case.

It is mostly twice fired star line 300blk brass. I bought it new. First 2 loadings were all subs.

 

[Please Delete]

Further...what projectile are you basing the hornady data off? they have the 125gr solid copper projos that will be longer than copper jacketed lead for the same weight.

 

[Please Delete]

I would also look at Barnes load data for the 125gr solid copper vortex projo.

 

[alexs2006]

IFIN it were me...I'd start at 17grains and work up till it is a compressed load...staying under the 20 grains Sierra says. are the 125gr matchkings flat base?

They are indeed flat based.

 

[alexs2006]

Further...what projectile are you basing the hornady data off? they have the 125gr solid copper projos that will be longer than copper jacketed lead for the same weight.

This is the projectiles listed in the book.

 

[Please Delete]

They are indeed flat based.

start at 17gr and work up 20gr. look for pressure signs...yadda yadda, ymmv.

 

[Please Delete]

This is the projectiles listed in the book.

I'd go by Sierra's data if it is their projectile. be ready to pull down if you see pressure signs early on the ladder.