I've been trying to work up a load in my 7mm Rem Sendero using the 168 Berger VLD and Retumbo. Long story short, I'm repeatedly coming in just under 1 MOA. After much experimentation, 70.5 grains seems to be optimum in my rifle. Initial results were best with the bullet 0.010" off the lands. That's the first picture, and it's fairly representative of what I'm seeing. It wants to perform, but there's always that stray shot or two that just won't stay with the group.

Berger recommends experimenting with COAL at 0.010, 0.050, 0.090, and 0.130 off the lands to see whether the VLD likes more jump. They suggest that one of these will outshine the others by a wide margin. Well, the second photo shows the results of that test. Holding everything else constant, from left to right, top to bottom, you can see I gradually moved seating depth out from 0.010 to 0.130 off the lands. There are six shots per group (two three-shot groups fired at the same target).

I'd be hard pressed to tell a difference between them. They're all around MOA, and 3 of 4 are 0.9" or better for six shots. Not bad, but this gun will make one ragged hole with the right load. Not sure whether to try a slightly faster powder, different primer, etc.? All brass is PFL, and every possible step that can be taken to uniform the brass (including culling by weight, neck-wall thickness, and runout) has been taken.

Ideas? Loading into the lands is not an option. And please...don't suggest that I just "go hunt." I have other rifles with which I can just "go hunt."

I'd try another powder. More than once I've had my mind set on a certain powder for a certain cartridge/bullet combo, and it hasn't worked out, but another powder has been the ticket.

I'd second the different powder suggestion.

I'll be trying Magpro in my 7RM with that bullet.

BTW, what velocity are you seeing with those loads?

Haven't clocked it yet.

IMR7828 works well in the 7mm mag!

Youve got a great powder, I wouldnt change that, but I never heard of giving VLDs jump, no more than .005' is what Walt told me when I loaded some 95s for my 6mm rem, get that bullet around there and see what happens, hopefully the bullet will still be in the case, haha. Was barely hanging on in my 6mm cases.

Your first 3 shots look very good. You can try changing the powder. But remember too, that it`s your "first" shot and "its proper placement" which really matters on a hunt.

After someone has tried as many seating depths as the OP a different powder is the next logical choice, no matter how good Retumbo is...no sense in limiting one self!

I've seen different primers really make a difference. Surprised me actually.

No doubt!

How about fine tuning the seating depth? Choose the group that shot the best and move the bullet in and out .005", .010", .015" to see if there is a trend. You might be able to tighten up the groups with no other changes.

This is a factory package right? Using a inch pound torque wrench to tighten action screws the recommended torque. I did this with a 7 RUM Sendaro and it tightened up the groups. It has been a while since I owned that rifle, cannot remember the recommended torque. Thinking it was 70 in/lbs but not positive.

Have you carefully inspected the crown? I have seen 1 MOA groups reduce to 1/2 MOA just by freshening up a crown.

Keep us informed on your progress.

I don't know much about reloading but maybe trying the next accurate charge down(whatever that was since 70.5 was the best) and messing with the distance off the lands and see if you get a better result with it. Might be the cheapest and easiest first thing to do.
Then again you can try a different primer since primers are fairly cheap when compared to buying a new powder.

I am currently working a load up with a buddy of mine leading the way. Shooting 154 interbonds with retumbo. Before I change my powder (if I need to), I would prefer to change OAL, then primer, and finally powder before I change bullets.
I hear and read about good results with H1000 about as much as I do with Retumbo with the Bergers.

I am just answering this from what I percieve to be the easiest and most cost effective steps first.

Kique

All that's been done. This is more about the VLD and less about the rifle. Berger recommends a very specific test for COAL and the VLD, and this post pertains to that test.

I am going to try a few different primers. At some point, I'll just give up on the VLD. I can't see racking up a round count of 200 on this barrel just to get the VLD to print.

What brand primers are you using now?

Good point.

May want to try 180s. That is the one I am planning on running when the 9 twist rock gets back. Also have a box of those 168s on the way to though.

my rem 7mm sendero has never shot a 1 inch group. usually .5 or less. i use re-19, however H-100o and H4831 are also good. the fed215 give higher velocity , and higher es. i use wlrm, rem 9.5, and cci250. 010, 020 or 030.

I just quickly skimmed over this really quickly.... I assume 100 yards?

Try 200-300 yards. My 257 wby never shined too much at 100 yards, but prints 2.5-2.75" groups at 500 yards...

Just food for thought.

Fed 215 is what I've been using. I'm going to try the magnum WLR, CCI, and Remington. I think I have some of all of them. It'll be worth it just to see what effect, if any, the primer change has on them.

Yes, 100 yards. It's hard for me to go to the woods with a load that doesn't shine at 100 yards, but I know what you're saying. It may settle down out past 250.

You've been very lucky. I have H-1000 and RL-19 at the ready; I think I'll try the primer switch first.

Try some RL-22. Why so bent on getting the Bergers to shoot anyway? mtmuley

Ive always used Rem 9 1/2, but that was with IMR4831, I think them 215 are too hot of a primer unless youre trying to ignite more than 80 grains, try a slightly less "hotter' primer like the WLR or even the 9 1/2, and try to seat that VLD .005' from the lands if you can. Good luck.

They have an ultra-high BC. Also, I like a challenge.

The 162 Amax has a higher BC.

625 vs. 617

Richard,

Retumbo should do it however if you want to try another powder give 7828 a try first. I have tried H1000 and H4831 and RE22 in my 7 using the Berger 168's and even though the others were descent 7828 and Retumbo worked better for me.
A couple of those groups were pretty good. Did I read in your original post you were shooting 6 shot groups? If so I would try the best looking combination and do a couple of three shot groups. From the looks of your targets I am betting 3 shot cloverleafs under .500".

Dave

I'm not sure that the performance is equivalent on big game. At least the demonstrated performance.

Dave, I usually shoot five shot groups. I can pretty much count on one being away from the other four every time with this load. My rest setup is BR quality; my scope is an 18X Swarovski with an ultra fine reticle, and it's got a Jewel trigger set light. And, I can shoot.

There is something about this load that just isn't quite "on," and, while it's good enough, it isn't good enough for me. I'm like that. This rifle will make one ragged hole when everything is right, and it will do it over and over again.

All the hunting reports I've heard on the 162 Amax have been stellar.

Much better than the Berger I'm told.

This from VERY experienced hunters who've used them extensively.

I'll find out this hunting season since I'm using these two bullets as my primary bullets in both my 280AI and my 7RM.

I haven't heard that. Honestly, I'm skeptical of both bullets, but I'm going to go out on a limb with the Berger. Call it morbid curiosity.

I may be placing too much emphasis on the fact that Berger endorses their bullet for hunting, and Hornady emphatically states that the AMax isn't suitable for hunting. I've toyed with the idea of testing the AMax in the field, however.

Bryan Litz tested the BC of a lot more bullets for the second edition of his book, and lists the 162 A-Max as .599. Since he does the testing for Berger, that's where the .617 BC for the 168 VLD comes from.

When working with a new bullet I normally try 2-3 powders and find which one shoots best before dinking with seating depth. If you're determined to use Retumbo (an excellent powder in the 7mm Magnum) it wouldn't hurt to try a couple of other primers.

I've shot quite a few animals the VLD's, and seen probably four times as many shot by other folks. They work just like Berger says they do on game.

Thanks JB. I'm going to try an assortment of primers with the 70.5 grain charge and Retumbo. It was a ladder test that got me to that starting point. If that doesn't work, I think I'll try both H1000 and H4831SC. I also have RL-19, but I'll likely have worn out my barrel by then.

Interestingly, I tried a few of the HSM 168 VLD loads, as a friend had a box of them. My gun shot them extremely well. Out of curiosity, I pulled one of them apart, and it looked an awful lot like H1000. The charge was 70.2 grains, however, and that's slightly over max as stated by Berger. May be something else.

I don't know if it makes a difference or not, but I have a trophy hunter from a few years back that has one of the best of the west guys talking about loading and stuff.
They loaded 168 Berger and 73.5 grains of Retumbo for the speed of 3076FPS using 9 1/2 primer I think. I have data I found online that was obtained from Berger that 70.6 was max for the 168 and Retumbo. HSM has the same 3076FPS as the article in Trophy Hunter. Wonder if there is anything behind that or if the exact speed is just a coincidence?
So if the powder is slightly over max, it wouldn't surprise me since most loads from what I have learned from others are consevative.

As a comparison,
According to Hornady my max should be 70.2 or something like that for the 154's, I went to 70.4 and can probably hit 70.6 without preassure signs(I hit preassure at 70.8). They claim 2900FPS and I got 100+FPS better than that.

Sure wish I knew what your Speeds are with those bergers. I wanna try some out of my 7 mag. Its a 700 sps with a 26" tube.

Good luck buddy!
Kique

I would think Retumbo is too slow to get good consistent working pressure.

FWIW, QuickLOAD only calcs 51K psi with the 70.5gr charge.

Thanks. I'll post my speeds when I get my chrono out again.

Interesting....I didn't know that. That's 10k under max. I'm also getting sooty case necks, which can indicate an under pressure situation. Now I'm compelled to try a faster powder. I've got 7828, H4831 SSC, H1000, and RL-19.

I'll tell you that at 70.5 grains Retumbo, I'm just starting (barely) to get extractor marks on the case head. Of course, that's in Miami in July.

I've got to get myself a copy of QuickLOAD.

If you're getting ejector marks, then the sooty case necks are most likely not indicating low pressure. You can't go by quickload estimates, go with your ejector marks.

And use your chronograph, if you're running at pressures where you're getting obvious pressure signs, it'll be the best thing you can do.

PS, just my opinion, but if I were getting ejector marks, even slight ones, I'd look at dropping down or using another powder before I'd start optimizing OAL.

I agree. Sooty case necks can indicate other things, and you can't have low pressure with high-pressure symptoms. One of the conditions has to be false. Of course, high pressure signs are not exactly a science either.

I sort of expected this gun to print better at a shorter COAL, which immediately eliminates any and all pressure signs in this gun with this load. Didn't happen, however.

You're right, high pressure signs are not science. But people much smarter than me have observed that once you get them, you're usually operating above safe pressures.

And if I had to choose either ejector marks or Quickload to believe, its a very easy choice.

If you want science, use your chronograph.

Lots of things can cause a transient pressure spike. If you're operating at the top of or above safe pressures, you've lost your safety margin. To me, the extra fps are not worth it, but suit yourself.

Kique,

I corresponded with John Burns recently about 7mm Magnum loads. He quoted the same load to me, and was with BOTW a few years ago. But he also made sure to point out that his 7mm RM's (Greybull) have longer throats than factory standard, so can take a little more powder.

That noted, Retumbo is a fine powder with heavier bullets in the 7mm Remington Magnum, despite what QL may indicate.

You misunderstood my last post. I'm not advocating operating with pressure signs; on the contrary, I was lamenting that I'd ultimately have to step down from this load if a change in components or seating depth didn't cause the signs to go away. Maybe I wasn't clear.

If you look at the original post, this was an experiment in seating depth, and only at 0.010" off the lands did I have light ejector marks. At all other seating depths, they went away. Whether or not a change in primers would cause the marks to go away remains to be seen.

I could really care less about the velocity. I'm after accuracy. It just so happens that the VLD is shooting best right off the lands, and this is where pressure, naturally, is going to be highest. Life sucks...really no surprises here, I guess.

You really need to chronograph the loads you are using. That will clear up a lot of speculation regarding pressure.

Sooty necks and ejector marks could be high pressure that built slowly, or it could be FL sized brass imprinting a boltface. Or it could just be a boltface that isn't square with the chamber.

It's your best indicator that you're getting near max. Safe pressures. Especially valuable with pressure signs.

Im thinkin' youre running about 3k.

i like 7828 ssc, i am running 66.5 grains in once fired weight sorted cases, 3023 ave for 40 rounds, SD of 12, will shoot .5 moa out to 800 yds or so, kreiger #4 contour 26in long,,,,i tried retumbo and h1000, never got the accuracy and only a little more speed,, i know i weigh all cases, +or- 1 grain is one lot, heavier is a lot, lighter is a lot, out of a bag of 50 wincehster brass i get around 30 that are close to the same,,i adjust my loads to 3025fps or so with each lot of brass, if i get to 2950 or so my gun does not group as well, about 1.2 MOA,

What I was trying to say in the post from which this excerpt was taken is that I'm not loading the 7mm for max velocity; accuracy is what matters most to me. I acknowledge the utility of velocity readings as one approaches pressure limits.

The TOP said it all! I always shoot my loads using at least one Chrony and many times I use 2 of them just for the record.

My first move would be a different powder or a different primer if your stuck on Retumbo. Powder change usually makes the largest impact, but I have seen primer swaps bring things together as well. My first move would be to grab two more powders, r22 and IMR7828 would be high on the list.

The 162AMAX shoots outstanding in my SFII 7RM over just about any powder/primer/brass combo you throw at it. It's done so-so with 140VLDs thus far(.5-.6moa). Just bought a box of the 168VLDs to try, but they'll have to really shine to beat the 162AMAX.

Good Luck

loder