7RM Load Development Results – Advice Moving Forward

[cajun]

I will add that picking the right powder is most of the battle. For example H 4350 in any creed variant. Sometimes guys want to or have to just use what they have on hand and wind up wasting components trying to get a square peg in a round hole.

 

[Mike Matteson]

The natural case stretch is your variable of concern for reloading. Measure the headspace and see how much these vary. You should expect the hottest load on virgin brass will be over pressure on 1x or more fired brass.
With your Norma brass:
If you anneal the shoulders properly you could accelerate the fire forming on the next reload using 1x fired brass.
You have to look at headspacing to see how much variation you have now vs the next reload.
Probably why the 7 PRC is becoming the cartridge of choice (over the 7RM) using the Alex Wheeler reamer during chambering on new barrels.

What I don't see is: loading powder down and putting the bullet into the lands. 1. to push the case base back into the bolt faces and then fire form the case. Making the case stretch at the shoulder rather than the base. Base stretch is where generally you lose the case in a few firing.
Presently setting up a 7mm in a 700 Rem that I had purchase back in the 70's. Sat in my gun safe until now. Presently in the smith for trigger, stock, bedding. My brother love's his 7 mm Mag.
So I have a reloading sheet on 7 mm mag loading. So I am enjoying the infor.

 

[Mike Matteson]

I will add that picking the right powder is most of the battle. For example H 4350 in any creed variant. Sometimes guys want to or have to just use what they have on hand and wind up wasting components trying to get a square peg in a round hole.

That H 4350 has been a go to powder for me over a great many years.

 

[bballard]

What I don't see is: loading powder down and putting the bullet into the lands. 1. to push the case base back into the bolt faces and then fire form the case. Making the case stretch at the shoulder rather than the base. Base stretch is where generally you lose the case in a few firing.
Presently setting up a 7mm in a 700 Rem that I had purchase back in the 70's. Sat in my gun safe until now. Presently in the smith for trigger, stock, bedding. My brother love's his 7 mm Mag.
So I have a reloading sheet on 7 mm mag loading. So I am enjoying the infor.

Sounds like I could be your brother! I recently pulled out of my safe an old early 70's BDL that I purchased cheap. I had it bedded and the trigger straightened out. It wears an older 3x9 Redfield lo-pro. It was put away and other things took priority. First time out shooting it a few weeks ago...produced cloverleaf at 100. Of course the calibers is 7mm rem mag!

 

[Mike Matteson]

Sounds like I could be your brother! I recently pulled out of my safe an old early 70's BDL that I purchased cheap. I had it bedded and the trigger straightened out. It wears an older 3x9 Redfield lo-pro. It was put away and other things took priority. First time out shooting it a few weeks ago...produced cloverleaf at 100

What type of load were you using? If I remember correctly it didn't have a box of shell shot. So it's a new rifle. Having a Boyd Adjustable Stock put on it. It was an ADL, but I am having it converted to a BDL. I putting a Leupold on it. TriggerTech in, put only between 1 & 3 lbs. It's going a friend that isn't to use to shooting that much.

 

[bballard]

What type of load were you using? If I remember correctly it didn't have a box of shell shot. So it's a new rifle. Having a Boyd Adjustable Stock put on it. It was an ADL, but I am having it converted to a BDL. I putting a Leupold on it. TriggerTech in, put only between 1 & 3 lbs. It's going a friend that isn't to use to shooting that much.

My favorite load for all of my 7mm mags is a full dose of reloader 22 and a 160 grain nosler accubond. If I need more bullet weight than that, I would just move up to my 300 win mag and 200 grain accubonds.

 

[Mike Matteson]

i use 165 AB in my 308 NM, and 200 AB in my 338WM. FPs in the 308NM is 3300fps, H4350 and the 338WM W760 is 3320fps, Both are about 5grs over max. Flat primers no creatoring in either one. I normaly use H powders due to weather or temp change. I haven't develop a different load for my 338WM. I someday will get the new 338WM from the smith with a 28" barrel.