Postal Shoot Prep

[KVW]

I was running the 39's at about 3750. I noticed last year that it was starting to loose accuracy at the comp shoots that I do. Wrote it off that it was me. This year I shot terrible at the first 2 shoots that we had. Checked my scope, changed my shooting style, nothing worked. Changed to 35 gr berger and tested with the same powder and won the last comp shoot that I was at. I've got between 300 and 400 rounds down her. Maybe it just settled in and doesn't like the 39gn anymore.

[Verminator2]

KVW, mine did the same thing with the 39 gr. I had them going about 3750 and after running 500-600 rounds they didn't shoot great and then they started keyholing Switched to the 32 SBK and it shoots just as good, going about 3750 too.

[jo191145]

FWIW My tube went through "The Change" too. It was shooting 40 Bergs and Benchmark nicely.
Started playing with the 39's and then the Varmint Grenades at some hellacious speeds.
Went to shoot the P-Dog target right before the deadline and discovered my old load now stunk.

Switched to my old favorite 35 Bergs and it was shooting again.
This particular barrel didn't like the 35's when new.

KVW if your still using Viht powders pay close attention to the case neck expansion.
When you pull an empty out of the chamber slip it over the next bullet in the box. If it doesn't fit over a bullet your seeing the Vihtavuori curse.
No known cure at this time besides jamming into the lands.

[KVW]

Hey JO191145,
I checked my 35 grain loads with what you said and they drop right in after shooting. My other gun shoots 39gr yet and you are right, the bullet will not go in after firing. What causes this.

[jo191145]

KVW I told you, its the Vihtavouri curse Sorry couldn't help myself

Sorry to be the one to point this issue out to you but then again you are now the second person to be afflicted by the curse as far as I know. Welcome to the club of Futility.

Club Futile I'll call it because I shot roughly 1500rds of Viht 135 and 40 Bergs trying to solve this problem and get the magic back. It sure was magic in the beginning too. One evening in the beginning I had 43 rds left over from an egg shoot. At 200yds every group was under .25 moa. except one. This last group I intentionally drastically misaligned my front rest to see what the effect would be. It shot a .64? under those conditions.

I'm not an internal ballistician by any means but I think the pressure curve of Viht powders are just so "smooth" this issue will arise whenever your jumping a bullet as far as we are.

Heres a few of the things I've learned
Annealing seems to help slightly but not enough. Even if you anneal after every firing. I even used some of my thin wall (.010) Win brass super annealed and still had the problem. You can fix it a little but in comp shooting one flyer puts you out.

Jamming 40 Noslers into the lands solved the problem but accuracy with my tube was not the best.
Start at the bottom! Pressures and accuracy nodes are nothing at all like when jumping. The best node was at 35?? fps and I consider that a tad slow for my tastes.

Audette ladders always pinpoint the most accurate node right at the point between expanding and not expanding. I've tried N-133, N-135, N-140 and N-530 with different bullets and this seems to be a given.
Even N-133 and the 26gn VG's showed me this. I never did try N-135 and 35 Bergs though it did show some promise when the barrel was brand new. After trying BM and H-4895 with the 35's I came to the conclusion this barrel did not like the 35's. Maybe that conclusion was wrong then, it is now.

You can go higher in the charge weight and the brass will begin expanding reliably. None of my Viht loads were ever mild as far as velocity and primer indicators. Accuracy usually suffers. Trying to hit the next node is very dangerous and better accuracy can be had with different powders.
My N-135 load for the 40 Bergs netted 3750fps. The next "good" node was at 3960. EXTREMELY high pressure and very dangerous place to be. Guns and brass are being pushed to the very edge up there. I popped a few primers but after a case rupture the dream was over.

I tell you this so no one will be tempted to overcome the issue this way or expend the time and money I did. Also everyone should agree we're not discussing wimpy loads here.

There might be a few things I didn't think of trying at the time but I gave up.

After a brief attempt at using N-133 with the new Varmint Grenades I'm done with Viht powders in the 204.
I bought two 6BR's to burn it up in.

Folks I realize this curse does'nt make sense but I've lived it.

Sorry for the long post
KVW if you have any other questions PM me.