making precision reloads for win 308. a few specific questions

SteveB said:
I disagree with using Lapua small primer brass but it is your choice.
Steve
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I agree
Some guys like the small primers and others hate them. 46 grains of powder is a lot to light with a small primer. I had a hell of a time with hang fires with 38 grains in a 6x47. I figure small primers might be ok on hot summer days only and really doubt they'd be any good this time of year. I had quite a conversation with David Tubbs on this very point and he used large primers on the 6XC for this very reason.
 
I would start by getting as much Lapua Brass as possible with the same lot number.

I use the Redding .335'' TiN bushing.
 
Wet Work

I found the same thing years ago when playing with the 22 Cheetah which is a 22-243 using a small primer. Most disconcerting hearing a click then bang. However, my main concern is safety using the overpressure loads that have been developed.

I am not saying Varget won't work with 200's but simply there are better choices for the same ES and higher velocities with no pressure issues.

Steve
 
This thread reminds me that I need to spend more time shooting and less time reading threads like this. :D

One thing to add, is that neck turning with 100% cut as someone suggested will thin out your neck, creating more expansion and work hardening with every shot. You can also look into getting a tightneck reamed chamber. You must anneal often to save brass life.
 
curseyou said:
This thread reminds me that I need to spend more time shooting and less time reading threads like this. :D

One thing to add, is that neck turning with 100% cut as someone suggested will thin out your neck, creating more expansion and work hardening with every shot. You can also look into getting a tightneck reamed chamber. You must anneal often to save brass life.
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^^^This is a valid statement if you have a factory chamber. For this reason you should really only neck turn if you have a custom chamber with an appropriately sized neck. That being said - the necks on Winchester brass tend to be thinner than Lapua. So if a person was to start with Lapua and turn to Winchesterish neck thickness - then you would still be within the range of reason and could get by. But the work hardening is a valid point just the same.

Another problem you will encounter when neck turning with a factory chamber is a problem with runout. The greater the amount of resizing - the greater the potential for sizing induced runout. When you have a tight chamber and are only resizing a couple thou then you cannot induce much runout and ammunition is more accurate.
 
Regarding using Varget with heavier bullets, why are some folks suggesting a slower powder? Does this only apply in longer barrels i.e 28-20"? Is it since the heavier bullets are slower, that the burn time will be longer before the bullet leaves the barrel?

I will be trying out some 208 AMAXs and 210 hybrids, and have been using Varget and N140 in lighter loads. Would it be worth trying something like N150?
 
Alpheus said:
Regarding using Varget with heavier bullets, why are some folks suggesting a slower powder? Does this only apply in longer barrels i.e 28-20"? Is it since the heavier bullets are slower, that the burn time will be longer before the bullet leaves the barrel?

I will be trying out some 208 AMAXs and 210 hybrids, and have been using Varget and N140 in lighter loads. Would it be worth trying something like N150?
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The rule is that powder burn rate must be decreased as the bullet weight is increased. Varget works well up to about 185 grains, but any heavier than that and you need to start working with a slower powder. That's not to say that you cant use varget - you just need to reduce the powder charge which results in lower velocity than you would get with a little slower burning powder like N150 or 550.
 
SteveB said:
I anneal every loading for my match brass. I use the annealing process to make sure I have no water in the cases after the cleaning.

Steve
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Thanks Steve! Every little bit helps. While we're on topic, I could use some help getting the most accuracy I can out to 1000 m with a 24" 308 with 1 in 10 twist using Sierra 155 Palma bullets and Varget. I haven't done enough testing with 175 to determine it as a better solution. While I can maintain 1 MOA for the better part (unless the wind kicks my a$$... that's another story LOL) I'm nowhere near the groups talked about earlier, especially at distance. Any help would be well received and greatly appreciated :) I know the fast answer is better gear but I'd like to get as much out of this barrel as possible before upgrading.
 
Veeshooter

It depends on what you are trying to achieve. The 155 bullets were built for Palma and sling shooting only due to the regulations of those sports. The 175 was built for US military requirements out of an M14. There are better bullets for match shooting out to 1000 yards (900 Meters). In F-Class the bullet choices seems to be narrowing to 3 bullets. The 155's from Berger, Sierra or Lapua, the 185 Berger Juggernaut and the 200 Berger Hybrid. Some people are using other bullets but these seem to be the dominant choices at the moment. For my suggestion, I would work with either the 185 and 200's simply for wind drift. F-Class is a known distance shooting sport so wind drift is your key requirement. Most guys I know are using Varget with the 155 and 185's and a slower powder with the 200's.

Research how to do an OCW test at 100 meters then after that do an OAL test again at 100 meters. Then switch to 300 meters and do a primer test. You should be GTG then for out to 900 meters. I have had yet to find a load that shot well at 300 that didn't at 900. However, I have had bullets that didn't work at longer ranges. The 168 Sierra is a classic example.

Steve
 
If I may, factory barrels will only shoot so well. If you can tune your loads for minimal elevation at say, 300yds (1/2 min or less), the group size will also be decent. Let's say you average 3/4 or 2/3 min over a 15rds spread at your test distance. For a factory barrel, I'll take it!

Keep track of how your group changes with each shot (ie as the barrel heats up). They almost always warp and they will have a pattern that will repeat. So say, the barrel starts to rise to the right as it heats up, you have to mentally account for this in your string and creep lower and left. HUGE PITA but it will let you shoot "tighter" groups with the factory barrel.

This is the best time of year to test this as your barrel can go through the widest temp range in a short time and you will see how it changes on target. Then cool down time is much faster so you can repeat a few times to verify.

You may also find that the best loads change as the barrel temp changes so you may need a few loads to account for the temp and tuning change. This is typically adjusted by powder charge and you need to find if more or less is better.

Then there is accounting for any change as it fouls. Again, you may need to adjust your loads to keep that barrel in tune. It becomes a massive logistical nightmare as you use this for that and the other for something else.

There is a big reason why we just go to match barrels. As a rule, they offer both improved accuracy and reduced handling headaches.

Jerry
 
Amen on the 168. I haven't seen any results from them beyond 700 to 800 really. I think one of the agenda items for me is creating enough velocity from that shorter barrel without over pressuring. I'm shooting more tactical style competitions with known and unknown distances out to 1100 yards as opposed to F-Class but the pin point accuracy is a must at any rate :) The more variables I can eliminate, the better. I'm going to give the 185's a try for sure on your suggestion, mainly because I have a keg of Varget to go through. What would be your powder suggestion on the 200's? Will I have any trouble stabilizing these heavier bullets with the gear I have? From what I've seen, folks are running with much longer barrels.
 
Jerry,

You just made my head hurt LOL. Many thanks for the insight and suggestions. I plan on doing some extensive testing over the winter months to try and figure this out. If all else fails.... match barrel here I come.
 
On a calm day, at say 200 or 300yds, start shooting slowly watching wind flags and mark on a piece of paper/target where every shot lands.

I put up 3 targets on the same level and shoot 5 rds at each target. watch where each shot lands and record.

If you take 15 shots on the same target, pretty soon shots overlap and get lost.

If your barrel warps, there will be no doubt that you start to see your group grow outside of the target center and elongate your group further and further away from center. Looks like a tail trailing off away from the center.

Or.... the group slowly gets larger and larger.

cool the barrel down, repeat. Odds are you will start to see the same pattern after the same number of shots.... problem identified. Decide if you can live and cope with that or not.

A problem you know, although not ideal, can be dealt with as long as the adjustments don't push you too far from center.

If you find that after 15rds, you can stay MOA'ish and this is repeatable, you have a decent enough barrel to let you learn how to read the wind. At this point, you say - 4 ring on target is my "5". 5 ring on target is my "V".

Essentially, you shoot on a TR target sizewise.

As long as your shots land in the 4 or better, you are shooting to the potential of the rifle and doping conditions well. In fact, if you never go outside a 4, you are shooting superbly and very competitive to your peers.

Know the potential of your gear and shoot to that potential. That is how you will learn and improve. We all want 1/4 min laser zappers but the budget to acquire and maintain may be beyond some at the start.

If you can dope conditions, each shot, every shot to the potential of your gear, you are actually shooting better then a lot of mega rifle shooters

Wind is everything in F class. Best gear to competitive may only vary by 1/3 min. How much we miss conditions can be measured in minutes sometimes.

Do not discount the Hrn 168gr BTHP or Amax. for the Rem, the Hrn 178gr amax might be ideal. These are much more affordable and for the barrel you are using, may not shoot any worst then Bergers.

Watch the flags and learn the mirage....Your rifle will get more accurate over time.

Enjoy...

Jerry
 
Alpheus said:
Regarding using Varget with heavier bullets, why are some folks suggesting a slower powder? Does this only apply in longer barrels i.e 28-20"? Is it since the heavier bullets are slower, that the burn time will be longer before the bullet leaves the barrel?
Click to expand...

Just to add a little to the reason why,
A longer heavier bullet is harder to accelerate/push, so if you stick to a fast powder normally used for lighter bullets the load must be decreased to stay in a reasonable pressure range that won't blow your brass or worse. Slower powder allows you to stay in a reasonable/safe pressure range as it allows a bit more time for the heavy bullet to start moving, without having to lose overall energy(how much gas the powder generates) by lowering the load. Of course at some point more of the combustion takes place in the barrel and its life decreases, and short barrel might not have time to burn all the powder if its really too slow or doesn't light well enough and you gain nothing. Part of why a chrono and care in watching pressure is important if you want to get the most out of it.





As to the original question, I plan to do more testing about meplat pointing this year, some say it makes a difference but I kept changing too many other variables all last year to tell if it did anything for me. I don't see it hurting anything though, but in the end maybe I should just spent more time shooting than fussing about it.
 
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