Question about Lapua 6.5 CM small rifle primer brass

[parkerg31]

So I recently came across about 20 pieces of unfired Lapua 6.5 Creed small rifle primer brass that a buddy gave to me to try and load. Currently I have a great load that shoots lights out with a .5" group at 300 yards. That load is 42.3 grains of H4350 with 140 gr ELD-Match projectiles. My question is where to start a load with the Lapua brass to try. I do not have enough to do a full ladder test, and figure that the brass is thicker than hornady brass so I will require less powder. What do you guys think?

 

[Milo 2.5]

So I recently came across about 20 pieces of unfired Lapua 6.5 Creed small rifle primer brass that a buddy gave to me to try and load. Currently I have a great load that shoots lights out with a .5" group at 300 yards. That load is 42.3 grains of H4350 with 140 gr ELD-Match projectiles. My question is where to start a load with the Lapua brass to try. I do not have enough to do a full ladder test, and figure that the brass is thicker than hornady brass so I will require less powder. What do you guys think?

You're not going to find a suitable load with just 20 pcs of new brass anyway, especially comparing it to your fired brass load. Start at 41gr and fire the brass over a chrono and get a feel for what is going to happen.

 

[Niles Coyote]

If you are using Hornady brass currently, you can just start with the same powder charge and +/- a tenth on ether side. While the case volume is different, it isnt much.

 

[b6graham]

Probably not much to do with 20 pieces unless you get another couple hundred, preferably in the same lot.

I'd work up a load for hunting or something and keep them separate since your current load works so well

 

[CUBUFF89]

FWIW I'm at 43gr H4350 with the 140 ELD-M in my Lapua brass. Fed 205 primer. Certainly different lots of components from what you're using.
It's safe in my rifle so I'm just giving a point of reference. You would have to work up a powder charge for yourself. You should weigh the Lapua brass vs. the Hornady brass to get a feel for their respective case capacities.

 

[Yerman]

I’m doing an OCW test tomorrow with the same brass and powder. I’ll let you know what I come up with. I’ll be shooting Berger 140 Hybrid Targets.

 

[Kadams1563]

I’m at 42.2 of H4359 with the 140 eld. (2820fps)

I went up past 43 grains without pressure signs.

 

[Kadams1563]

I’m at 42.2 of H4359 with the 140 eld. (2820fps)

I went up past 43 grains without pressure signs.

H4350

Couldn’t figure out how to edit my post.

 

[Yerman]

Here is the Raw Data from this morning.

Note, we are shooting the same brass, powder, and bullet weight. Only diff is I'm shooitng Berger vs Hornady. Not sure about your barrel length, twist, or primer.

I'm shooting a 26" barrel with 1:8 twist, BR4 Primers.

Data came from a Magnetospeed V3.

 

[Yerman]

Here is the same date with the Min and Max removed as outliers.

 

[parkerg31]

Here is the Raw Data from this morning.

Note, we are shooting the same brass, powder, and bullet weight. Only diff is I'm shooitng Berger vs Hornady. Not sure about your barrel length, twist, or primer.

I'm shooting a 26" barrel with 1:8 twist, BR4 Primers.

Data came from a Magnetospeed V3.



View attachment 6915400
View attachment 6915401View attachment 6915402

This is awesome man I really appreciate it! Ill load a few at 42.0 since thats what you had some good results with and because it is not far off from my current load already.

 

[JOE62]

Your data falls in line with my findings also. I’m using 41.9 and so far it’s the most accurate. I haven’t checked the speed on mine. What seating depth are you using for the Berger Hybrid Target?

 

[Crowe284]

Here is the same date with the Min and Max removed as outliers.

View attachment 6915403View attachment 6915404View attachment 6915405

What software is that?

 

[Yerman]

20 thousand off lands

It’s actually just a spreadsheet available for free from 6.5 Guys. Here is a link to the video. It’s best to watch this first so you know how to use it. There is a link in the description to download the file.

 

[Yerman]

Also, I’m actually leaning towards ~42.5. I like how it’s flattening out and still maintaining low SD and ES

 

[JOE62]

Also, I’m actually leaning towards ~42.5. I like how it’s flattening out and still maintaining low SD and ES

Thanks. I’ve done a little adjusting on my seating depth and it seems.040 works best for my stick. I started getting faint ejector marks at 42.0.

 

[Crowe284]

Thanks for the link to the video and spreadsheet!