Load development

[bowhunterjae]

Hay all,
Looking for a little insight from the crowd.
Started load development. For my new rifle.
I Found good es? (on my old chronograph). Loaded some rounds and just wasn't getting groups I wanted.
So I Invested in the new Garmin Chronograph and I started over.
This is what I have this go around.
Trying to give all of the information I have below.
7mm RM
Valhalla long magnum action with Wyatt box
Shilen match stainless barrel with 1-8" twist
Gentry quiet brake
Timney trigger set at 2 1/2 lbs
Redding type s sizing die, Redding seating die for Berger 168/180.
Peterson brass, Federal 215, 40 thousandth off jam.
Here are the powder charges, projectiles and speeds.
Thank you in advance,
John

 

[338 dude]

I would load more rounds from 70.5 to 71.5
And adjust seating depth to fine-tune groups

 

[ShtrRdy]

Did you shoot groups with these powder charges or just one shot at each powder charge?

 

[338 dude]

Did you shoot groups with these powder charges or just one shot at each powder charge?

Looks like just one looking for pressure I guess

 

[bowhunterjae]

Yes, I shot groups.

 

[bowhunterjae]

these are the 180 grain Bergers with H1000. I let the barrel cool between shots. It was a 4.5 hour process. Ones on the left were first three the right was the last

 

[bowhunterjae]

These are the 168 grain Berger with H1000. Ones on the left were first three the right was the last

 

[bowhunterjae]

The 180 Bergers with Rutumbo. Ones on the left were first three the right was the last

 

[bowhunterjae]

I shot all shots off of bags in great weather conditions after letting barrel cool. Brass did not show pressure signs.

 

[ShtrRdy]

Then I'd go with the 67.9 gr of H1000 and the 180

 

[YZ-80]

It looks like you'll get there. Is the Redding die a bushing die and do you know what kind of neck tension you are getting off the press? Uniforming primer pockets and chamfering flash holes might calm things down a bit too. Never loaded for the 7mag. Don't know if they like a longer jump or not but I always start at .02 off and have rarely moved closer than .015. Too many variables, too little time!!

 

[bowhunterjae]

Yes, bushing die, .0015 neck grip. These shots were all 40 thousand off of jam.

 

[RUFFIAN R - NY]

One of my favorites is my HART custom built 7mmRem Mag with a 28 in bbl. I don't give out load info only cause each gun is different and ones loading practices is different. Hart made up my loading dies when he was chambering my action. Using L E Wilson chamber type blank die body both for bushing sizing die and for seating die. I like the Nosler 160 gr Partitions or the 168 gr AccuBond Long Range bullets. Sorry but am a Nosler bullet guy, for all my hunting rifles / pistols. I stick to one lot of brass which makes a difference old benchrest days. Which helps in the loading practice and less variables, that also goes for the bullets ( all same lot ) I do make a practice of checking all my bullets prior to loading and put them in batches and keep well marked within my standards. Again throating will make a difference and bullet seating depth will very by ones chamber. Do wish you luck with your build as for me, am getting a little too old to worry about building any more toys but might just go for one more ??
SHOOT STRAIGHT AND OFTEN: I load for accuracy not speed.

 

[southpa]

Ummmm what's wrong with the one hole group with 180s?

Is this barrel broke in? If not I'd load around that small group of 180s and see what happened when it speeds up.