Berger VLD bullets in .308

[geetarman]

I went to the range today to test my .308 loads with Berger bullets.

Following the Berger suggested method, I loaded 10 rounds with the bullets touching the lands.

I loaded 10 more with the bullet backed out .040 in. from the lands.
I loaded 10 more with bullets backed out .080 in. from the lands.
I loaded 10 more with the bullets backed out .120 in. from the lands.

All loads were new Winchester brass sized and WLR primers and 43 gr. H380.

There were no signs of pressure and no problems with extraction. I am going to try to get the pictures posted. . .

To say I am pleased is an understatement. The loads at -.04 and -.08 were really great. The group went away a little at -.12 and not so good with the bullets in the lands.

I am waiting for a competition seating die to arrive so I can tweak the loads again.

I know that -.04 and -.08 work well and groups are similar. My thought is to load up another batch at -.045, -.055,-.065 and -.075.

I am doing this on the premise that the groups at -.04 were converging and the one at -.08 was diverging from the theoretical "sweet" spot.

If that is true, then another round should yield some interesting results. After that, I will tweak the powder charge a little at a time and see if the groups improve.

Geetarman

[geetarman]

Here is the last group with the bullets backed out .120 in.

[Unclenick]

You're on the right track. When you've tuned the seating depth, the next step is to tune the charge of optimal barrel time. Dan Newberry's method is a good way to do that and the round robin can be adapted to finding seating depth too.

I notice you've got a bit of horizontal stringing in all the groups. That can be stock contact with the barrel, but can also be a sign you need to have your bolt lugs lapped. It could, however, simply go away when you get the powder charge tuned.

[geetarman]

I think the horizontal stringing might be from removing the rifle and letting it cool during the cease fires and not placing it back on the shot bag exactly the same way.

The rifle is a 700P bull barrel and the barrel is free floated. That does not mean that I always get the rifle bagged the same way. I use the bags at the range and sometimes change my grip a little. Just another one of annoying variables that contribute to not putting all the rounds in the same hole.

I am unaware how lapping the bolt lugs would contribute to stringing. Could you elaborate a little? Please?


Just another thought. I was not placing my hand under the stock to support the rifle off the bag.

I have seen my groups change quite a bit when I have my hand between the rifle and the bag.

Do you normally just use the bag for forward support or do you use your hand in addition to the bag?

Geetarman

[Unclenick]

The lug lapping is because if one lug touches down while the other does not (or touches only slightly), the initial pressure bears mainly on the solid side. That asymmetric bolt thrust can strike up a lateral vibration.

I would try moving the front bag back under the magazine floor plate for grins. Sometimes that can tighten a group up, though you'll want some scuff protection between the bag and the metal.

Hand contact is something you have to experiment with. Some benchresters do it all with the bags and only touch the trigger, letting the gun back up into their shoulders. Some other guys have a death grip on the gun. Whatever you do, the trick is finding something you can do the same way every time.

[geetarman]

Unclenick,

Thanks for the response. My computer tried to quit on me yesterday and I had typed a follow on but somehow the message is floating in the great bit bucket in the sky.

I think the issue of horizontal stringing is more me than the rifle.

Yesterday, I did some things that I have not done before.

There were some strings that were interrupted before they were complete.

I try to look at the time remaining before a called cease fire before I start a string and did not do that.

I switched out the .308 for the 22-250 several times. Normally I shoot one and then the other.

I was moving the rifles back and forth to the rack rather than leaving them on the bench as I normally do.

The rifle has a composite stock and aluminum bedding block and the barrel is free floated. I can see that there is clearance all the way down the stock and it is not touching the barrel.

I personally have not run the sheets of paper drill to see if anything is touching on the bottom. Given the type of stringing, that would not be my prime suspect for the problem.

I have almost a 1000 rounds through the gun. This problem showed up yesterday and I have looked at other groups I have shot and stringing does not seem to be an issue.

I have a few boxes of 168 gr. Noslers loaded up and will load up some more Bergers and go back to the range next week ( I hope ).

If the problem shows up again with the Bergers, I will shoot a box or two of the Noslers and see if the problem continues or not.

I was "visiting" with a friend shooting on the bench next to me a lot and as a result, was not strictly taking care of business.

I had two cups of high test coffee before I went to the range. I normally do not do that on the mornings I shoot, I will not make that mistake again.

By mounting and dis-mounting the rifle from the front bags as much as I did yesterday, I introduced new variables into the equation.

The last thing that I noticed yesterday that I never noticed before was some sort of felt vibration in the bench. I have a 32X scope on the 22-250 and I noticed quite a bit of fluctuation trying to stay on target and some sort of felt vibration on my right elbow. I have a 20X scope on the .308 so the visible fluctuation was not there but the felt vibration was. They are doing some construction in the area and I do not know if that is the issue or if possible small aftershocks from the recent earthquake were present. It is something I have not experienced before and I will be looking for it next time.


My whole work life was spent in process control. It has been my experience that 20 percent of the variables cause 80 percent of the variation.

I need to work on reducing the influence of those variables.

Thanks for the advice. I will let you know how it turns out, If I need to get the rifle worked on, I certainly will.

Geetarman

[geetarman]

Unclenick,

Attached is a 20 shot group of Noslers. I shot this last summer. 10 shots and then let the barrel cool and then 10 more shots. I think I was shooting IMR4064 in these loads.

Geetarman.

[Unclenick]

Except for the two most extreme shots, that's pretty round. It makes me a lot less suspicious of the gun. Just try running one of Newberry's round robins and see what you come up with?

[Wildalaska]

I need to work on reducing the influence of those variables.

Ditch the Winchester brass in favour of Norma or Lapua, unless you are weighing and measuring your cases

WildinvariableAlaska TM

[geetarman]

Wildalaska,

I have noticed some variation in the loaded round that can be attributed to the brass.

I do have 100 Hornady match brass that may try. I hear a lot of good things about Lapua and Norma brass but have not tried them.

I am anxious to take the 40 rounds that I loaded up Saturday and see how they do.

Can you elaborate a little on the reasons you dislike Winchester brass?

Thanks!

Geetarman

[Brian Pfleuger]

Originally Posted by geeterman

I hear a lot of good things about Lapua and Norma brass but have not tried them.

I don't have any experience with rifle brass except Norma, and even that's minimal, but I can tell you that out of 40 samples of 7mm-08 brass, using CCI BR primers and Hornady bullets, not one single finished round varied more than +- .9gr, and that was only two rounds. The rest were all with +- .5gr. For comparison, my 357sig Speer brass varies by that much when it's empty, and the case weight is about half of the 7mm brass.

[Wildalaska]

Can you elaborate a little on the reasons you dislike Winchester brass?

Inconsistent

WildnotmatchgradeAlaska TM

[Unclenick]

Geetarman,

Winchester mixes brass off different forming machines. I first sort it by weight. I mark the bottom edge of a sheet of paper with the case weight range in 0.1 grain increments and set each case above its weight on the paper. This way the cases line up above each other to form columns that serve the purpose the bars in a bar graph do. It's a histogram with distinct peaks that indicate which machine and tool set the cases came off of.



I next sort those grouped weights by neck runout. I usually end up with about 20% of the total set that are excellent long range match brass. I prefer sorted Winchester .308 brass for long range because it has more powder capacity than the other brands. The lightweight design was developed as match brass for the 1992 Palma match. It actually works pretty well if you get all your ducks in a row and eliminate the more extreme errors in the bulk cases you buy.

If you read Newberry's site, you'll see all his recipe loads are made with unsorted Winchester brass and he gets them shooting half moa. So, unless you have a problematic chamber or bullet, it is usually going to be hard to see the difference better brass makes until your groups are already in that size range. I own enough Lapua .308 to have demonstrated that to my own satisfaction, anyway. YMMV, though. There are always exceptions in this kind of thing.

[geetarman]

Unclenick,

You are a WEALTH of information. I had not considered such an experiment.

Your data is mind boggling. I do not know if I will ever get that involved, but you have certainly made my day.

I wish I had met you years ago.


Thanks for pointing me in a direction I had not considered.

I will sound off when I get a chance to run the new loads down range.
I do have some Hornady match brass. I have no idea how good it is. . .but I am going to find out.

Are you still in the workforce? What do you/did you do? I really am curious now.

Geetarman

[Unclenick]

Geek engineer. Not yet retired, but running my own show (part of the time, anyway). Makes it possible to find time to post that way. Maybe if I stop posting I can figure out how to get rich? Oh! Wait a minute. If I do that, the taxman will just take it to fund the pet projects of the financial drunken sailors we keep electing to office. Bother. Have to think of something else to do with my spare time. Wait a minute. I've got it. I'll post in Internet forums. . .

[geetarman]

Unclenick,

I hear that. I retired from Boeing a couple of years ago. I did a lot of process control work for coordinate measuring machines. Really got into it when I managed a metrology lab for Colt Industries. When I had problems measuring something more than once and not get the same numbers, I started asking a whole lot of questions.

Then I started applying what I learned to reloading and shooting.

Still not where I want to be but I am farther down the road now than when I started.

Trying to really understand the variables at work and how to reduce their influence really intrigues me.

I will be out at the range Friday to test my theory. We will see how that goes.

I do like the spherical powders for the loads I am working on but would like to get better results with the old standbys like 4064,4895, 4831 and 4350.

I use a Dillon press and it really does not do such a good job throwing consistent loads when using IMR powders.

Any ideas on an equipment change that would help throw better loads with those powders?

I am thinking I may may use the Dillon to size and prime and use something else to load powder. It would mean going back to using loading blocks like I did with my RCBS. The RCBS powder thrower did a fair job of cutting through stick powder and had a fairly long throat so the powder was not so likely to bridge over. You could also whack the handle to break jams free.

Any advice?

Thanks,

Geetarman

[Wildalaska]

Winchester mixes brass off different forming machines. I first sort it by weight. I mark the bottom edge of a sheet of paper with the case weight range in 0.1 grain increments and set each case above its weight on the paper. This way the cases line up above each other to form columns that serve the purpose the bars in a bar graph do. It's a histogram with distinct peaks that indicate which machine and tool set the cases came off of.
I next sort those grouped weights by neck runout. I usually end up with about 20% of the total set that are excellent long range match brass. I prefer sorted Winchester .308 brass for long range because it has more powder capacity than the other brands. The lightweight design was developed as match brass for the 1992 Palma match. It actually works pretty well if you get all your ducks in a row and eliminate the more extreme errors in the bulk cases you buy.

Unc, I love ya, but while your plotting histograms, Im just pulling Lapua brass out of their new plasticboxesthatdoubleasanammoboxes and loading em.

WildandgeetarmaniselllapuabrassascheapasmidwayAlaska TM

[Unclenick]

Geetarman,

Yes. The JDS Quick Measure meters stick powders within 0.2 grains. It has a design that can't cut grains; they are either included or excluded. JDS makes a Dillon adapter for it. This page shows the measure and a little picture in the upper right shows it adapted to a Dillon and will link you to the adapter. I don't believe it does any kind of neck expansion, as the Dillon measure does, but in rifle loading that's not normally necessary. Just chamfer. Not exactly inexpensive, but once in place, it works really well.


Wild,

I hear ya. I have a good supply of .308 Lapua that I can't find enough fault with to sort a single case out of it. I did discern that it came off two sets of tooling, but they are very close (see graph below) and I did go ahead and sort them by tool set just to do it. It's amazing how close each tool set makes it. I've never found more than 0.001" neck runout in any of mine. I bought 700 new Norma cases when I decided to build a 6.5-284. Same story.

The reason for the Winchester is that its semi-balloon head design (average weight 156 grains at my last bulk purchase) has almost two grains more water capacity than the Lapua, and that lets me get another 25-50 fps MV, depending on the barrel length and powder. Not a lot, but for 1000 yard targets, specifically, it can spell the difference between staying clear of the transonic range and not doing so.

[geetarman]

Back from the range. Have some pictures to upload.

First pic is 150 gr. Speer btsp and 44 gr. IMR 4064. Poor group
Second pic is Berger 175 gr. seated to standard OAL and not seated in the lands. Powder was 42 gr. IMR4064. Nothing to brag about.
Third pic is Federal Trophy 168 gr. Sierra Matchking. Not too bad.
Fourth pic is 175 gr. Berger at -.045 off the lands over 43 gr. H380.
Fifth pic is 175 gr. Berger seated -.055 off the lands over 43 gr. H380.
Sixth pic is 175 gr. Berger seated -.065 off the lands over 43 gr. H380. This is the best group of the day and I think I am ready to start tweaking the powder charge.
Seventh pic is 175 gr. Berger seated -.075 off the lands over 43 gr. H380.

Looks like group is going away.

It seems the rifle really prefers the heavier bullet ( 168 gr and heavier ).

I am happy with the progress so far.

Geetarman

[geetarman]

Next three pics..

[geetarman]

Last pic.

Thanks to EVERYONE who helped me some really good tips. I owe you!!!

Geetarman

[Unclenick]

Whew! Just glad to see all that stuff we make up actually works!