Frustrating trip to the range

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GSoD

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Hey,

This is mostly to vent but also try to get some perspective.

I'm loading for FClass.

I had built up a nice little load with 175SMKS seated to 2.945, Federal Brass, CCI Large Primers and 44.5gr Varget. It would do between .6 - .7 groups all day long with an extreme spread of about 25fps and a standard deviation of about 10 and an average velocity of 2690. I weigh all charges and use check weights on digital scale. Shoots out to 1000 yards nicely.

But I'm chasing that elusive .5MOA (stupid tiny vbulls).

So I treated myself to some Lapua brass and Federal Match Primers.

Start working the load up with 175SMK and the new 155Palma SMK. The 175s are left at 2.945 and the 155s I start at the recommended 2.775.

On work up, they both print about .35" at 100 yards at 45grains of Varget on 3 shot groups.

So I load up 10 of each.

Shoot 5 at 100. They both pattern nicely at about .450" centre-centre

Then I shoot 5 at 200 awaiting confirmation of my sub .5MOA load.

Oi

The 155s put the first 3 shots into .935" outside to outside edge. But then 1 goes right and one goes low right to push it to 2.410" outside to outside. The last two had a big velocity drop for some reason. Going from just over 3000fps down to 2850?

The 175s? They don't even stay within 3 inches. Looks like a shotgun.

Thinking something must be wrong with me or my gun I throw in 5 rounds of another load I've been playing with. Same as the 155 load except with Hornady Match Brass. It patterns at 1.615" edge to edge.

Now the only difference I can think of is that I'm using new Lapua brass straight out of the box. I mean straight out of the box. No sizing (waiting for my new dies) no nothing. They are all within a grain of each other weight wise and approx the same case length and I skip the ones that look like they have obvious case mouth damage. The others have gone through my gun at least once and have been FL resized.

So I guess the questions are:

a) Do you think the new / unsized brass is to blame for the wildness? And I should wait for my dies to come in, size them, then hit the drawing board?
b) Do you think I maybe just pulled those two shots on the 155s and totally blew all 5 on the 175s? And should collect myself load up as per usual and try again?
c) How does something that work so good at 100 go so wrong at 200? Up to now it's been a straight correlation. If differences in the virgin brass are to blame, wouldn't it show up at 100 as well?
d) By the time of the wildness I'm at about 50 shots between cleanings, could fouling be the culprit? Again, why not at 100?

Just pissed at myself because at 100, I thought I had it. Then 200 pwned me and ruined the rest of my day.
 
If you are laoding for F calss, you should do your load development at a longer range. I amim at a patch on the back of a target or wear center at 300 yards, minimum. On a calm day I test at 500 yards. 100 results do not translate into anyhthing meaningful at real distances.
 
A switch in the mirage and/or wind, if you are not watching, can open a 5 shot group up in a real hurry.

If your group at 200 had good elevation dispersion and it was windage calls that opened the group, then I would say it was the loose nut behind the bolt.

If you had both vertical and horizontal dispersion, then you need to tune the load some more. Perhaps with seating depth and/or powder charge.

At your listed OAL how far off/into the lands are you? Where are you getting your "recommended" OAL from? SAAMI specs?

You need to find out where your bullet needs to be seated in relation to the lands of YOUR rifle.

I always start my load development with Sierra bullets seated just kissing the lands and Bergers jammed .015 into the lands.

Sierra's typically liked to be jumped and Bergers seem to work best Jammed .015-.020.
 
I once had a bad scope that cost me *months* of lost time and frustration. Do you have a different scope that you could try?

(BTW I'm intrigued at the very big difference between the COAL for your 175SMKs vs the #2156 (right?) 155s. What chamber are you using? I thought that the #2156s gave COALs in excess of 2.9" even with super short (e.g. Warner 95 Palma) throats?)
 
Thanks for replying guys.

Granderite: Agreed. But 200 yard range is all I got to work with :(

CyaN1de: The vertical was less than 1" It was mostly a push to the right. Maybe somethign did sneak up on me or I just flubbed it. It was pretty calm, but there was a twisting tail breeze that would kick up once and again.

The OAL for the 175s is something I've worked up. I think (don't have my notes at work) 2.975 was where my lands started and I shot groups reducing my .010 until best grouping. The OAL for the 155palma SMKs were from the Sierra website.

rnbra - I did just put a new scope on. Perhaps I should check mounting. It's just a stock Rem700P chamber.

So if nobody thinks that using the virgin brass is a probable problem, perhaps what I'll do is load up another batch. And then a couple of test batches working on the seating depth.

Also, I don't know if this is a problem or not, but when I look at my federal match primers the flashhole side is green. Is this normal? My CCI's are red. Perhaps a bad batch?

Thanks again guys, needed something to talk me off the ledge yesterday.
 
I would start at the lands (if you can) and find the best grouping powder load THEN adjust seating depth in .005 increments to tune the load.

Sounds like your on the right track.
 
GSoD said:
Also, I don't know if this is a problem or not, but when I look at my federal match primers the flashhole side is green. Is this normal? My CCI's are red. Perhaps a bad batch?
Click to expand...

Green? That means they've been left on the counter too long and gotten moldy. I'm heading down to the hazardous materials place later, I'll take all of the green primers off your hands, I won't even charge you for my trouble. :yingyang:
 
Are the primers Gold Medal Match or blue box? I just looked at my GM primers and the sealant is red. Do you have an OAL guage ? This will help setthe seating depth. As for the Lapua cases I did not have problems with mine throwing shots while fire forming, I have not tried the new SMK yet but will soonly, they are apparently finicky about seating depth.
 
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