First 6br almost complete!

[Texas10]

With 30 grains Varget (plus or minus half a grain) 107 SMK's a touch into the lands, and CCI450's you should find some very, very small groups, well under 1/4 moa if the the nut behind the bolt is doing a good job..LOL.

Upgrade to a better target bullet and groups get smaller. With a 6BR, what's not to like?

 

[Fast14riot]

Reminds me of my rifle. But a 14 twist for GH. I would like to see the groups. I do the opposite I don't care what the fps is I just want small groups with good speed, not the most I can get away with. Don't believe in finding accuracy by looking at fps. Don't believe in flat spots in velocity. Looks like you want to push the limits by putting the most powder in the case you can get away with.

Not looking to push the limits of the case, I was watching for pressure signs, but I am looking to take this rifle to 1K and with only a 24" barrel I don't want it going trans sonic. 2800fps gives me roughly 1350fps still at 1k.

Its not a heavy barrel, so the magneto speed did play with harmonics a bit. Now that I know my powder charge window, I will do seating depth test to try and tighten up groups.

 

[Fast14riot]

With 30 grains Varget (plus or minus half a grain) 107 SMK's a touch into the lands, and CCI450's you should find some very, very small groups, well under 1/4 moa if the the nut behind the bolt is doing a good job..LOL.

Upgrade to a better target bullet and groups get smaller. With a 6BR, what's not to like?

Yep, seated to touching with "square marks" from the lands, I used 7-1/2 primers because its what I have the most of. Next test should put up some smaller groups.

 

[Fast14riot]

Got to take this rifle out to 1K yesterday. After zeroing I realized I didn't have enough elevation left in the scope to get to 1K, so I very carefully removed the rear scope ring cap and put in a set of +/- .020" inserts, then used a collimator to roughly keep it on zero. Took only 4 shots to get on paper at 1K as I didn't have time to put any confirming shots on paper at 100 yards before, and I apologize to the guys in the pits for the shot I skipped off the berm, lol!

Once on paper, shooting this slow, light bullet in a full value wind condition really made me realize how much easier it is with a 140gr bullet going 3000fps vs this little 107 going 2800. I'd find a good condition and get several 10's and X's in a row, then it would drop 2-3mph and suddenly I shoot an upwind 7 or 6, lol! But, I built this for 600 and in, so I expect it to be a little easier to correct for wind than at 1K.

Match format was two 20 round matches with 4 relays, because the temp was forecast to he 110° and it was a club practice match, so short and sweet. I shot a 362/400, not great, but right in there with the middle of the pack. So far, I'm still happy with it and now to tear it apart and get it painted!

 

[Fast14riot]

Did a neck tension test yesterday and finally got it shooting how I expected it to, groups around .25-.3moa. Now I need to get my brass prep dialed in, had a couple that were hard to close the bolt on, needed another thou of shoulder bump. Those of course landed outside the group.

Still enjoying this build and its coming together nicely!

 

[JFrank]

Did a neck tension test yesterday and finally got it shooting how I expected it to, groups around .25-.3moa. Now I need to get my brass prep dialed in, had a couple that were hard to close the bolt on, needed another thou of shoulder bump. Those of course landed outside the group.

Still enjoying this build and its coming together nicely!

Interesting that those rounds landed out of the group

 

[Fast14riot]

Interesting that those rounds landed out of the group

AFAIK its pretty common. It happens for me in my 260AI as well, usually printing high.

 

[Texas10]

Lately my Fred Moreo built 6br has been throwing shots, leading to poor scores while shooting "light varmint for score" meets at my local club. I changed scopes and rings but saw no improvement. Last month I shot my worst score since starting competition with this rifle, and long work hours have left little time for investigation.

But after last months poor showing at the match, I decided to re check the bullet seating depth. i'd not done it for a while and the results were that due to throat erosion my seating depth on the 107 SMK was no longer .010 into the lands, but .010 OFF the lands. Not a happy place for the bullet in my rifle!

I loaded up with a new seating depth and shot a few practice rounds into some nice one hole groups.

We'll see how it (or I) shoots tomorrow at the club match and I'll post the results.

 

[boltman13]

My Savage action with a Criterion 1:8 twist, 28" barrel and VV N140, 28.5 grs. jumping 0.005" gave me 2,705 fps for 10 shots and an insane SD of 2. It's a heavy F-Open and IBS 600 yd. BR gun. I am going to try 28.8grs. and see if the SD doesn't crap out and what velocity I get. Guys with dual port actions who can run their bolt and stay in a condition are very competitive at 600 & 1,000 yds. BR with the 6 BR. Your Remage and my Savage action make that very hard, however. You seem to be getting good results and should get even better ones. I am saving the little Varget I have for now, and playing with the N140 and Nosler 105 RDF's weight sorted. My rifle with Berger 105 Hybrids and Varget 29.5 grs. is capable of 0.25 MOA out to 600 yds. if I do my part. Best of luck.