.308 155gr Scenars kicking my ass

Slavex

Slavex

Morning Star, The Lightbringer
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So been working up a load for the sniper match this weekend. 46.5gr. Varget 155gr Scenar virgin Lapua brass and BR2 primers.
OAL is 2.895 2850fps velocity.
I'll shoot one group at about .25-.3 of an inch then next group 1 inch. Shooting Ed's dots I'll hit 7 or 8 with good solid hits then throw one an inch and a half out. WTF?
 
You need to ensure that your left foot is slightly off the ground..and your
tongue hanging out, also slightly left..so you can feel the wind changes..:p

sounds like you are doing most things right..do you find its the last of the string..or do the flyers show up any time...you need someone to watch you fire the group ol pal..and watch for the little things that make flyers..;)
 
Hmm flyers do tend to be the end of a group. Fatigue (laziness?)? Maybe.
I'm cleaning the pig tomorrow then heading out thursday to foul it/practice in the afternoon if you wanna come along Long Bow.
I swear I never had this problem with the 168s
 
I'm having way better luck with the 168s and 175s in my TRG than 155s.
The one concern I had when loading them that far out is there is very little bullet and neck contact - not sure if that may be an issue.

I'll be using 175 Berger VLDs over 42 grains of Varget, 210m primers with Lapua brass at 2.900" oal. Just fits the mag, nice and light load and has been shooting very well so far.

I considered using the 168s for short line and coming with two loads as they shoot that much better out to 200m than the 175s, but that is too much work and dicking around.
 
Slavex said:
Hmm flyers do tend to be the end of a group. Fatigue (laziness?)?

Trying to hard????? ;) could be several things...something is changing between shots.

Love to go to the range, but I'm in VGH, just had surgery # 12...this time they used a patch made of "Bovine" and "Shark cartlidge"..lol
hope it helps with the disengaged eye stuff..be home in the morning..but not supposed to stand or walk around for a couple days..thanks though bud.
HH says hello..been in to visit a couple times
Click to expand...
 
I'll double check bullet and neck contact but I'm pretty sure its fine. The Scenars are virtually identical to my 168gr MK for where the neck contacts. I could shorten them up if need be.
Nothing like ####ing about right before a match.
Long Bow, say hi to Badguard for me. And best of luck with the grafts. Let me know when you're up for company.
 
Slavex, this may be totally irrelavent to your rifle.

I had a very similar problem with my CZ550 F class rifle. Upon inspection, I found some oil in the bedding. I cleaned it out with alcohol, retorqued the screws to their normal sweet spot and all was well.
 
God I hate this problem!!! It can drive you crazy!!!. What is the twist on the barrel and why change if 168's didn't give the problem? Maybe the preference for 168's is a clue.
 
TRG-22, 1 in 11 twist.
I changed from the 168's as I won 400 of the 155 Scenars last year at the prize table. 757fixer shoots them out of his TRG-22 with no issues. I'd been told they are the best thing going yada yada, so I figured give it a go this year. never expected any issues at all. If I had 200 168's and enough Ball C2 I'd be going back to that load right now.

I know that seating the bullet deeper will result in higher pressures, but how much of a change can I expect dropping back down to 2.85 from 2.895 with the same load? that's the length I was using with the 168's. Bearing surface is much better at that length, only about 3/4 of the case neck was touching the bullets at 2.895
 
I'd wagger quite a bit. I was getting a tight bolt at 46 grains Varget and 155 Sierra Palma's at 2.850". Velocity was hovering around 2900 ft/sec.

The most accurate short load I've found has been 44.5 gr. Varget with 168 Amax 2.850"oal with a velocity of 2650 ft/sec.

A caveat to all of this is I only have around 500 rounds through it so far:rolleyes:
 
OK, TRG-22. Factory chamber, I assume? And I'm guessing a 26"-ish barrel?

At 2.895" overall length, are you clear of the lands, or are you engaged?

1 - Your charge weight sounds slightly hot-ish to me (I use 45.0 Varget, Lapua brass, Lapua 155 @ 2.840", which in my chamber is about 10 thou into the rifling). I've never been able to get extra-hot loads using the Lapua 155 to shoot well.

2 - But, your velocities sound low-ish to me (my load gives me about 2950fps, in a 30" barrel; in a 26" barrel it might give 2875-ish).

Based on (1) above, I would suggest that you try 1 grain less powder. But based on (2) above, I would suggest not lowering your charge. How's that for contradictory??!!

I wonder what is going on. Maybe you have quite a long throat, and a fairly slow lot of Varget.

If you are presently quite near, or into your lands, I think you should definitely try seating your bullet deeper, until it is .020" to .030" clear of the lands (a la Ganderite). Don't worry about the minor increase in pressure this will give you, trying a touch more velocity (20-30 fps) is probably worth trying.

(if it makes you feel any better, I mucked around with Lapua 155s for about seven years, before I finally got them to shoot well for me at long range.)
 
Not sure where I am in relation to the lands actually. Its been a long time since I measured that and have lost the info. Gonna try back to 2.85 and the same load. Looking for pressure signs etc.
Will probably take the factory to the range tomorrow to play for a couple hours. Then make the final decision
 
Slavex, one of the old HBR tricks I used on my rifle, witch was chambered in 308Winm was to seat the bullets into the lands. Every couple of hundred rounds or so the seater had to be backed off a bit. HBR rifles are different from F Class in that they have tight necks that have to be turned down to accept a cartridge. They also use lighter, flat based bullets and have 1-15 twists.
There was a fellow with a 1-14 twist barrel that shot a lot of Hornady 155 grain bthp match bullets. He didn't have any problems with bullet stability at all and was pure hell to go up against in a match. Nice guy, darn good shot and his wife can shoot as well as he can. Unless your velocity is very low and from what you say it isn't, I don't think stability is your problem. Any chance of a badly fouled spot half way down the tube?
 
Bore looked good after cleaning yesterday. Nothing obvious or showing up on patches. The TRG barrels don't really foul too easy I've found. Detail stripped her and will reassemble in the morning when I get home. Will torque everything back down and then hit the range in the afternoon.
Thanks for all the tips and ideas guys. Its much appreciated.
 
Slavex, a thought occurred to me after posting last night. Don't mix load development with match shooting, if you can possibly avoid it at all. Do you have any other bullets on hand that you can use in a "known-good" load for the sniper match this weekend?
 
nope. hence all the hassle. not too concerned about the match honestly. I'm a pistol shooter who shoots sniper stuff once a year. I'd had no second thoughts on this new load and didn't expect any trouble with it. had I thought it would be such a fun time I would've sourced my normal stuff earlier. too late now!
 
to get the 155's to shoot from my gun i had to run them into the lands everything else just gave me a shotgun pattern effect. i must have tried 20 different combos and shoot 300 plus rounds before i got it to work. just like you my gun shot the 168 vld like a lazer but like always when somthing is working too good i have to try to fix it.
 
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