Sorry for getting on my soapbox the other day.

I really like H 4350 but I didn’t want to use it up for this project.  My 6.5 needs it more.  The process that I’m trying to use is not mine.  I just stole it from a world class competitor.  Actually he lays it all out on his Forum, Cortina Precision, Shooting Small Groups.  If you research what the pro’s are using that can get you started and not waste a lot of components.   I did not have that luxury with this project so I started with what I had.  I’m hoping to get groups like Chris showed.

I have one of the higher charges left so I will use these to warm up and foul the barrel.  I still have 4 groups at the lower charge weights to shoot.  Then I’ll pick 1 or 2 to see which seems best and then play with seating depths.

Just for comparison here is a pic of my new 6.5 barrel with the 270.

If you can stand it watch this video.  Start at the 5 minute mark.  I follow Erik Cortina and watch all of his videos.  He has won world class matches and on normal YouTube he can’t show the how to side of things.  But on his pay forum he can.

This is how I learned to do my powder and bullet seating techniques.

t=17s

I shot 4 more loads yesterday.  Very windy and only 52 degrees.  It appears that I need to shoot 5 more next week to narrow it down a little.  I believe this set up likes speeds in the lower 2,700’s.  I am anxious to get to the bullet seating tests.  This old barrel will never get target accuracy.  I am hoping to get as close to 1″ as I can.

TXGunNut said
I suppose a standard sporting rifle, even one as nice as this one, can be a bit disappointing when treated as a precision rifle. As a precision shooter you know how to properly evaluate a group, too many folks will put three shots into an inch now and then and pronounce their rifle “MOA”. I’ve only owned one sporting rifle that would consistently shoot sub-MOA and it shot five shots into .67″ more than once. If I could keep from tossing that last round out it would put 10 into under an inch. Some of today’s modern rifles are apparently pretty amazing but I haven’t had a hunting rifle capable of much under 1.5″ @ 100 with tailored handloads in awhile. As you know industry standard not too long ago was rumored to be 3″ but so far I’ve only had a couple of modern bolt guns I couldn’t get under 2″, BACO replaced one under warranty and repaired the other after I spent hundreds of dollars on ammo, chamber gauges and components. 

I really think you’re gonna make this rifle shoot, Chuck. Apparently it’s going to be a bit of an adventure, though.

 

Mike

  

Not so much fun so far.  But I’m going to go through the entire process.

On Tuesday I shot 5 more groups increasing the powder charge 0.1 grains for each group.  I messed up thinking the groups would finally stay on the target.  But they did not.  I usually cover all the holes on the backing board with the target and then small stick on dots.  First group on the lower right was OK except the third shot went left.  Upper right looked better.  Then, the problem.  The first 2 shots missed left and with all the holes in the backer I had no idea what was what.  I moved my aim point right 2″ and the next 3 hit the target.  2 holes touched but the last shot went low.  Wish I could find the first 2.  So lower left I moved my aim point right and they all hit the target.  In fact I can only see 4 holes and they are all fairly close to each other.  The last group in the middle opened all up.  Weather was the best so far.  No wind and at least 20 degrees warmer than last week.

The missing bullet is there. We just can’t see it.  The top left group may have been good too but since I moved the point of aim and can’t know for sure where the first bullets went, I’ll never know.  Even the lower right target would have been better if not for the 3rd shot flyer.  All of these were in the high 2,600’s or low 2,700’s.  The next 5 will get a little more toward 2800.  And I will cover all the existing hole in the baker this time.

Loaded 2 rounds yesterday to replace 1 that I ruined and 1 that the primer pocket is really loose.  The Norma brass when new have an extra tight pocket.  But that doesn’t last too long.  Remember when I tried to uniform the un fired brass and the uniforming tool wouldn’t go in. After the first firing it would.  I ruined one primer yesterday and had to switch seaters just to do the 2.  I didn’t want to set up my normal seater and tried to use the one on the RCBS rock chucker. 

I measured the sized cases for headspace.  Just a little off for what I want so I’m just going to shoot them and let them grow.  Remember some of the first batch were .007″.  Max is .010″ and I want .002″.

SAAMI specs for the chamber size is a range not a set size.  Same goes for the head space.  Barrel makers tend to cut the chamber on the long side and ammo manufacturers load on the short side.  This way all ammo fits all chambers and are still in SAAMI Specs.  Lapua brass when new has .003″ of headspace in my target barrel.  Tighter tolerances on both ends.

I’m done with the powder ladder testing.  I was really surprised and disappointed that this combo can’t group at the higher speeds.

When doing the ladder testing you are looking at a few things.  You want to see a couple charges next to each other where the speed change, Delta, is minimal and the barrel is happy.  The ES of the group is good.  It is best to be under 20 FPS.  The position of the groups on each side of the one you are looking at is in the same relative position on the target. You don’t want to see major swings showing instability.  And finally group size.  We will continue to work on group size.

So I made a list of the best ES. (12 to 24 FPS).  Best Delta of the groups Mean average FPS. (1 to 14 FPS).  And the best group sizes.  (.724″ to .977″).

I am going to test 5 different charges.  I have not picked which ones yet.  I have to eliminate 1 charge.  I shoot 50 round batches because my ammo box holds 50 rounds. So 5 groups of 5 shots shot twice gives me the 50 rounds.  I will end up with two groups at each charge to evaluate.  

One thing I did notice is that 53.6 and 53.8 grains showed up in all of the parameters I was looking at.  Not the lowest ES but best Delta FPS and best groups.  Normally I’d shoot this at 53.7 grains.  If it works out you end up with a little room on each side of the load for scale error and such.

When you want to lower your ES/SD you need to work on your loading.  Get better brass, powder and primers.  Sometimes you have to try different combinations to find what your barrel is happy with.  Work on your loading techniques.  The ignition timing of your rifle is the only part of your rifle that effects ES/SD.  Good groups is the combination of your load, bullets, barrel and the shooter.

I started the cleaning process yesterday. Tumbled the brass and cleaned the primer pockets.  I need to brush the inside of the necks before I anneal.