7mm Rem Sendero with 168 Berger testing

[Dr. Vette]

Today I had a chance to test my 7mm Sendero with its first handloads.
If you recall, I recently had DrMike run a QL for me using a few powders, but today I used H-1000 as per his recommendations. My goal with the rifle is to attempt to do as well or better than the HSM ammo, which my rifle shoots relatively well at 3010fps.

Winchester cases (trimmed, annealed, etc) were used with Remington 9 1/2M primers.
Distance is 200 yards.
Chrono is my Master Chrony. It was about 50 degrees today, minimal wind.
Shooting was done in a round robin fashion starting at 68.5 and working my way up.
I spent a fair amount of time scouring the LRH site for loads using H-1000 and the 168 Berger, and almost everyone's "pet" load was 69-70gr, so I focused in this area.

See the attached targets for specifics. Note that the 2nd target and 4th target of the bottom row were used for other rifles, and therefore are not marked.

Interesting notes:

the loads with the best ES don't have the best groups (see 70.0 vs 70.5)
some loads have quite a bit of ES, and I have no idea why. I wonder if the second 68.5 should have been 2936, not 28?
The unmarked second target of the bottom row - the two far right shots about 1/2 inch apart are the fouler loads for this rifle with 68.5gr powder. I then moved the scope crosshairs over but you can see they were obviously very close together.

I'm a bit stumped as to which direction to go from here. I've tried to look at it from a "smallest group" perspective, or looking for a node, or looking at it from an OCW perspective. No answers jump out at me thus far.

Any thoughts from the experienced shooters?

 

[Guy Miner]

First thing I'd try is a much different bullet from the Berger.

The VLD shape is excellent! But... Not always the easiest to get shooting well. I love 'em in some applications. Your rifle may or may not have one of those barrels that like Bergers.

Try a conventional match bullet, or a ballistic tip hunting bullet. They're more forgiving. Easier to get the accuracy with.

Then, if you want to keep messing with the Bergers, make sure they're seated STRAIGHT in a STRAIGHT case, and then start playing with the distance to the lands. I found my Bergers don't like much of a jump whereas a conventional match bullet like a Sierra Matchking or a Nosler Custom Competition bullet can jump about halfway down the doggone barrel and still shoot well.

Just because the unique shape of the Berger isn't working well, doesn't mean your rifle can't produce stellar accuracy.

BTW, my best accuracy with the 7mm Rem mag came with RL-22, and some excellent velocity came along with it.

Regards, Guy

 

[Oldtrader3]

I have tested the 168 grain Long Range AccuBond in my 7mm Rem Mag. I am getting about 2870 fps with <MOA groups using 66.0 grains of IMR 7828 SSC. I have only shot a couple of croups so far but results are encouraging. Thanks Scotty for sending me the LRAB bullets to try.

 

[Dr. Vette]

Guy,

I get bugholes with the HSM ammo which uses 168 Bergers, so my assumption (!) is that the Berger will work fine in this rifle when I load it myself. That's why I picked the same primer, case and OAL for my loads. However, I know they use a different powder based on the case I took apart recently.

Cases are straight, and I picked 20 of the best to use in testing. Neck thickness is very consistent among them.

The rifle shoots some other ammo well, but I've got other rifles for other bullets, and this one has shown some ability to shoot the 168 Berger as noted above. Getting 2 of the loads under an inch at 200 yards isn't bad for accuracy (<1/2MOA), but the ES in the same loads is what has me guessing.

Then again, my 257 Weatherby gets <1/2 inch groups at 200 yards with factory ammo and I can't get it under an inch at 100 when I load it myself so...

 

[ScreaminEagle]

Seems like every 7mm mag Ive come across prefers flat base bullets.

 

[Bruce Mc]

You might try a different primer. I have used Federal and CCI loading H1000 in the 7mm mag and have gotten pretty good SDs. Winchester was the worst but I've never tried Remington. The other day I shot a group of 160 accubonds and 74grs of H1000 and Federal primers over the chronograph and got a SD of only 2. Thats the best SD I've ever encountered.

 

[Guy Miner]

Guy,

I get bugholes with the HSM ammo which uses 168 Bergers, so my assumption (!) is that the Berger will work fine in this rifle when I load it myself. That's why I picked the same primer, case and OAL for my loads. However, I know they use a different powder based on the case I took apart recently.

Cases are straight, and I picked 20 of the best to use in testing. Neck thickness is very consistent among them.

The rifle shoots some other ammo well, but I've got other rifles for other bullets, and this one has shown some ability to shoot the 168 Berger as noted above. Getting 2 of the loads under an inch at 200 yards isn't bad for accuracy (<1/2MOA), but the ES in the same loads is what has me guessing.

Then again, my 257 Weatherby gets <1/2 inch groups at 200 yards with factory ammo and I can't get it under an inch at 100 when I load it myself so...

Heck, consider just hunting with the HSM ammo! Worth noting by the way, that HSM has a long and interesting history of precision loads for the 7mm Rem mag. I wouldn't be surprised if they'd tell you what powder they're using, if you phoned them.

Also - yes I agree - you're already getting good accuracy for 200 yards. I know you want more out of that heavy-barrel Sendero... :mrgreen: And it's kind of a challenge when the HSM ammo shoots better. Grrrr. Something to aspire to...

Regards, Guy

 

[Dr. Vette]

Right now no one has HSM 7mm 168 ammo in stock - and after all, this is a reloading site where we try and do better, right? :mrgreen: Per Midway et al the next batch isn't due in stock until November.

My thought is to consider repeating the smallest groups and the one with the best ES to see if they are repeatable, and go from there. Not sure if that makes any sense or not.

FYI I say that they are not using H-1000 as the powder I removed from one of the HSM cases was 65.9 grains in weight, far less than the amount of H-1000 it takes to get 3000fps.

HA - I checked Midway looking for more bullets, and the HSM is in stock - who would have guessed. So, a bit more is on my way so I can shoot the rifle while I work up a load.

 

[Darkhorse]

Pick the charge, powder and bullet you want to use, then work with seating depth to find the node.
Simple. All my recent 7mag testing has led me to this process and for me it works quite well.
Not all bullets need to be seating into the rifling to get good results, sometimes a longer bullet jump will surprise you.

 

[desertcj]

The 70 grain load isn't bad for 200yds. Take that and play with the seating depth. Also try a different primer. Sometimes it makes a difference.

 

[FOTIS]

Right now no one has HSM 7mm 168 ammo in stock - and after all, this is a reloading site where we try and do better, right? :mrgreen: Per Midway et al the next batch isn't due in stock until November.

My thought is to consider repeating the smallest groups and the one with the best ES to see if they are repeatable, and go from there. Not sure if that makes any sense or not.

FYI I say that they are not using H-1000 as the powder I removed from one of the HSM cases was 65.9 grains in weight, far less than the amount of H-1000 it takes to get 3000fps.

HA - I checked Midway looking for more bullets, and the HSM is in stock - who would have guessed. So, a bit more is on my way so I can shoot the rifle while I work up a load.

RL22?