Pressure ring and neck tension

[PopCharlie]

I increased neck tension to .003, seated bullets to jamb +.009, +.012 and +.015. 90 gr Berger BT.

Looks like jamb +.015 and .003 neck tension is shooting better. I want to try .004 tension. Then start increasing powder charge to find the sweet spot.
PopCharlie

 

[Ccrider]

Hang in there. First, Reread what Randy said and follow his advice. I

I have the same setup in a dropport Rebel action. It will shoot much better once you get it tuned- like .1s and zeros at 100.

It would be helpful if you tell us what you mean by “jamb” or how you are getting to jamb. At some point as you move into the lands, you will not be able to go any further, regardless to how long you seat the bullet. That point changes as you adjust neck tension.

I would seat an unloaded round very long with whatever neck tension you intend to test, chamber it letting the bolt seat the bullet and then pull it out and measure it. (I use a rod to gently help push the round out if it sticks in the lands). That will tell you the maximum amount into the lands that you will be able to go with that neck tension. When I first started, it was easier for me to work backing off of that point to develop a load. I would start with a bushing .003 less than my loaded round and tune my powder charge with that. After getting dialed in, I would test neck tension to see if it got any better.

The other thing you need to know is what max load is for your gun using that bullet. The 2630 load you are working with is bad anemic. I have a couple of savage actions that easily handle more than that. With my Rebel, I can run over 3000fps with no pressure signs. Yours may be different so start low and work up. But get to a better velocity node if you want to see how good this the br will shoot. I expect it will be over 2900fps.

The neat thing is the hard work has been done for you. You can pretty much expect it to shoot between 2950-3000 fps.

 

[RGRobinett]

I increased neck tension to .003, seated bullets to jamb +.009, +.012 and +.015. 90 gr Berger BT. View attachment 1269180

Looks like jamb +.015 and .003 neck tension is shooting better. I want to try .004 tension. Then start increasing powder charge to find the sweet spot.
PopCharlie

Though a small sample, note how the velocity stabilized as you increased the "jam", which increased the pressure - a sign that Ccrider's powder advice is sound.
Most people using the BIB 95/6BR & various powder combinations (Varget/H48956/IMR8208/etc.) report MVs >2900FPS. DITTO [carefully] identifying the max for your rifle/component combination! RG

 

[PopCharlie]

Hang in there. First, Reread what Randy said and follow his advice. I

I have the same setup in a dropport Rebel action. It will shoot much better once you get it tuned- like .1s and zeros at 100.

It would be helpful if you tell us what you mean by “jamb” or how you are getting to jamb. At some point as you move into the lands, you will not be able to go any further, regardless to how long you seat the bullet. That point changes as you adjust neck tension.

I would seat an unloaded round very long with whatever neck tension you intend to test, chamber it letting the bolt seat the bullet and then pull it out and measure it. (I use a rod to gently help push the round out if it sticks in the lands). That will tell you the maximum amount into the lands that you will be able to go with that neck tension. When I first started, it was easier for me to work backing off of that point to develop a load. I would start with a bushing .003 less than my loaded round and tune my powder charge with that. After getting dialed in, I would test neck tension to see if it got any better.

The other thing you need to know is what max load is for your gun using that bullet. The 2630 load you are working with is bad anemic. I have a couple of savage actions that easily handle more than that. With my Rebel, I can run over 3000fps with no pressure signs. Yours may be different so start low and work up. But get to a better velocity node if you want to see how good this the br will shoot. I expect it will be over 2900fps.

The neat thing is the hard work has been done for you. You can pretty much expect it to shoot between 2950-3000 fps.

Thanks Ccrider. I find the jam the way you describe. I'm going to do some loading on Monday. I will be using .003 tension and .015 jam. I want to move the powder charge to get to the suggested velocity. I also plan to do a sanity check on the jam as well.

PopCharlie

 

[PopCharlie]

Though a small sample, note how the velocity stabilized as you increased the "jam", which increased the pressure - a sign that Ccrider's powder advice is sound.
Most people using the BIB 95/6BR & various powder combinations (Varget/H48956/IMR8208/etc.) report MVs >2900FPS. DITTO [carefully] identifying the max for your rifle/component combination! RG

Thanks Randy!

 

[AckleymanII]

PppCharlie, Your light load is killing you! Everybody has their own way.

My way is to touch the lands, with .0015-.002 bullet grip, work up in powder charge till you find small group. Then start tuning seating depth till the load turns into a "Hummer" load! Somewhere in there, I may play with bushing sizes, but it usually is not necessary due to very, very small groups.

It is possible that your freebore is too short for that bullet...I would make sure that the pressure ring is above the shoulder neck junction by .020 or so.

To my way of doing things, your method is azz backwards, and is the reason for your pulling your hair out. This is a hobby, make it fun for you!

Trying to tune a light load is like to trying to fix an unfaithful girl friend!

 

[PopCharlie]

PppCharlie, Your light load is killing you! Everybody has their own way.

My way is to touch the lands, with .0015-.002 bullet grip, work up in powder charge till you find small group. Then start tuning seating depth till the load turns into a "Hummer" load! Somewhere in there, I may play with bushing sizes, but it usually is not necessary due to very, very small groups.

It is possible that your freebore is too short for that bullet...I would make sure that the pressure ring is above the shoulder neck junction by .020 or so.

To my way of doing things, your method is azz backwards, and is the reason for your pulling your hair out. This is a hobby, make it fun for you!

Trying to tune a light load is like to trying to fix an unfaithful girl friend!

Yes, I know. I'm going to up the powder charge to get the velocity to +2900 fps. I've been loathe to run that hard though. I'll get over it because I want small groups more.
PopCharlie

 

[AckleymanII]

If your brass gets tight on the top end load where it is the most accurate, contact Harrells or Whidden for a die size to your chamber specs.....don't sweat the small stuff. I full length size mine every firing with a Harrells Die....very fine accuracy. I suspect that my chamber reamer is probably .0008 or more too small.

 

[PopCharlie]

PppCharlie, Your light load is killing you! Everybody has their own way.

My way is to touch the lands, with .0015-.002 bullet grip, work up in powder charge till you find small group. Then start tuning seating depth till the load turns into a "Hummer" load! Somewhere in there, I may play with bushing sizes, but it usually is not necessary due to very, very small groups.

It is possible that your freebore is too short for that bullet...I would make sure that the pressure ring is above the shoulder neck junction by .020 or so.

To my way of doing things, your method is azz backwards, and is the reason for your pulling your hair out. This is a hobby, make it fun for you!

Trying to tune a light load is like to trying to fix an unfaithful girl friend!

Yes, I know. I'm going to up the powder charge to get the velocity to +2900 fps. I've been loathe to run that hard though. I'll get over it because I want small groups more.
Pop

If your brass gets tight on the top end load where it is the most accurate, contact Harrells or Whidden for a die size to your chamber specs.....don't sweat the small stuff.

Already got Harrells to make a F/L sizer for me. I sent them 3 pieces of brass that had been fired 5 times in this rifle. I'm using it now to size the brass. I'm using Whidden bushings in it.

PopCharlie

 

[AckleymanII]

You are now ready to so some shore nuff serious shooting, push her to the limit, find pressure, unbelievable accuracy is right around the corner.

 

[PopCharlie]

Update: I loaded up some 95 gr Precision Ballistics boat tails with .004 tension, seated at jam + .008 (recommendation from Don Lahr who makes these). I walked up the powder charge in .3 gr increments. At 30.4 grs of Precision Rifle they started to group, avg 2809 fps. 30.7 grs got me to 2942 fps average and a nice group, but not where I want it yet. I'm going with this powder charge, and will adjust the seating depth to tighten up the group. I'll post some pictures a little later.
Thanks for all the help guys!
A shout out to Randy Robinette. I spent a good bit of time talking to him about shooting, wind flags, mirage and bullets.
Edit: Target pic attached.
PopCharlie

 

[PopCharlie]

One more pic:
This load is Berger 105 gr VLD seated to touch. 30.0 and 30.4 grs N540, .004 tension. Last 2 groups of the day, so unfortunately, I got sloppy. Notably, the 30.4 gr load shot an ES of 8 SD of 4. If I had not leaned on the rear bag for shot 2 and 3, it would have been respectable. 30 grs shot well too. I screwed the pooch on shot #4


PopCharlie

 

[Ccrider]

One more pic:
This load is Berger 105 gr VLD seated to touch. 30.0 and 30.4 grs N540, .004 tension. Last 2 groups of the day, so unfortunately, I got sloppy. Notably, the 30.4 gr load shot an ES of 8 SD of 4. If I had not leaned on the rear bag for shot 2 and 3, it would have been respectable. 30 grs shot well too. I screwed the pooch on shot #4
View attachment 1271869

PopCharlie

Why did you lean on the bag? No worries. At least you know you did it. You may be able to adjust your set up where your stock is extending past thebag enough to where you can shoulder the rifle without touching the bag.

 

[PopCharlie]

Why did you lean on the bag? No worries. At least you know you did it. You may be able to adjust your set up where your stock is extending past thebag enough to where you can shoulder the rifle without touching the bag.

its just a bad habit. I can usually tell when I do it. If I catch myself, I'll adjust.