Jackie, can U elaborate?

goodgrouper

tryingtobeabettergrouper
I took this off the other thread as to not hijack the thread but I thought it interesting enough to further explore.

Jackie, you said this:

Then there is a group of shooters who have discovered that the Lapua 220 Russian case allows the 6PPC, when fired in a properly set up Benchrest Rifle, to be shot at what can be best described as "elevated pressures". The school of thought here is that there is more to extreme accuracy, (the kind this Forum rerpresents), than simply finding the correct barrel vibration node. Allowing the powder to burn at it's most efficient rate (particuarilly 133) plays a big part.


Can you elaborate?

There seems to be several trains of thought as to efficiency. One view is expansion ratio. Another is powder/carbon fouling. Yet another is standard deviations in velocity. Of which of these were you describing?

I have found loads that literally blew out primers that seemed to be dirtier than old Red Dot shot on a cold day. So I don't much prescribe to that description. Expansion ratio is a very good indicator of what to expect in my opinion. Small deviations in velocity can show good combustion of that particular charge although not every charge with that powder yield same results.

If we are after nothing but accuracy, then finding the right node for it should be paramount without giving a care at all to efficiency. I know some guys would touch off 10 pounds of powder per shot down a 6mm hole if they knew it would drill "zeros".

Thanks.
 
GoodGrouper

For about the first four years I shot Benchrest, I tuned like most, I would shoot about 28.5 grns of 133, and tune in fine increments, hoping to find that magical sweet spot.

Then, I discovered the upper window. Right off the bat, I noticed that cleaning became a breeze. There just didn't seem to be much in the barrel after each group.

Also, the Rifle just seemed to stay in tune over a wider condition change. It finally evolved to where I would go an entire season and not change my load 2 tenths one way or another. I was also enjoying some limited success.

Then came the tuners. Now, the only time I change the load is when the humidity drops way down. I just go up a few tenths.

I really can't explain my whole idea of this high pressure thing, because I have nothing but my own anecdotal evidence to back up my hypothesis. But, I am convinced that at the level we shoot, there is more to a Competitive Tune than just finding the right barrel vibration node..........jackie
 
For about the first four years I shot Benchrest, I tuned like most, I would shoot about 28.5 grns of 133, and tune in fine increments, hoping to find that magical sweet spot.

Then, I discovered the upper window. Right off the bat, I noticed that cleaning became a breeze. There just didn't seem to be much in the barrel after each group.

Also, the Rifle just seemed to stay in tune over a wider condition change. It finally evolved to where I would go an entire season and not change my load 2 tenths one way or another. I was also enjoying some limited success.

Then came the tuners. Now, the only time I change the load is when the humidity drops way down. I just go up a few tenths.

I really can't explain my whole idea of this high pressure thing, because I have nothing but my own anecdotal evidence to back up my hypothesis. But, I am convinced that at the level we shoot, there is more to a Competitive Tune than just finding the right barrel vibration node..........jackie



Interesting.

I usually shoot between 29.2 and 29.9 grains of N133 and I notice it is very clean in this range. Is it similar to what you load? It must be a bit less as this range doesn't ruin brass as fast as you describe.
 
Goodgrouper,
I doubt if Jackie will tell you the exact load he shoots. But I think it is slightly above what you are using. I think I know but am reluctant to say as we have had a problem similar to this in the past.

To Jackie:
On your "elevated" load does it come almost to the mouth of the neck? And do you compress the powder when you seat a bullet? Knowing about what you shoot, I can't see how you could not be compressing the load. I can't get that much powder in a ppc case without compressing during bullet seating. Inquiring minds etc.

Donald
 
In a couple of my barrels I get my best results shooting an amount of 133 that when dropped quickly into the case seems to be the most that can be put in without grains falling off the edge of the case mouth after the drop. In order to move the level of this amount of powder down the neck, I use a long .22 caliber drop tube, and more importantly, drop the powder very slowly using 4-5 mini drops. To do this I slowly lower the handle of my Harrell measure until I see powder falling and then reverse the handle, stopping the powder flow. I repeat this until all of the charge is in the case. It is this dropping method that has the greatest effect on powder level for a given charge weight, more so than drop tube length.
 
Boyd,
Yes I have tried this and it is amazing how much more you can get in a case even with a 4" drop tube if you drop slowly and twirl the case a bit as you drop. Something on the order of 2 full grains. I was just wondering if Jackies load came far enough up into the neck that the base of the bullet compressed the powder some. Or on the other hand what about you? Even with a long drop tube do you compress the powder when you seat the bullet. That is what I am wondering about.....compressing the powder by seating the bullet, even when you use the long tube, etc.

Donald
 
If your cases are being trashed

after only a couple of firings with 30+ grains of N133 your full length sizing die is not set up correctly with your reamer.
 
Stephen, looks like you need to get out more. Wayne's dies he got off the ice cream truck has earned him almost 20 HOP points. How many do you have????
 
Dies, and Miss-Conceptions

Wayne makes the point that having a proper set of sizing dies plays a large part in how well your brass performs when shooting in the upper load window.

I guess there is a miss-conception when I say that brass is shot.
My definition of being "shot" might be different than someone elses.

I take new brass to every match, at least 25 cases for a Two-Gun event. Since I can interchange brass between all of my Rifles, I can use the cases in sequence. By the time the week end is over, I will have about 6-8 firings on each case.

I have spent a lot of time getting my dies (in my opinion), just right. They are a compromise of sizing the case just enough to faclitate easy feeding and extraction throughout that Two Gun event, and not overly working the case.

Yes, to many, the cases are still fine. I even give them to friends who shoot my chamber, and they are tickled pink. But, I have always believed that nothing shoots better than fresh brass, so I just go through a lot of cases.

Probably needlessly. But, it is what I do, and I am not going to change, that is, unless brass goes up to $5 a piece.

So, forget what I say about brass life. Shoot it untill YOU think it is ready for the happy hunting ground.........jackie
 
Stephen, looks like you need to get out more. Wayne's dies he got off the ice cream truck has earned him almost 20 HOP points. How many do you have????
Not to mention winning the the World Benchrest Championship they year it was in Sweden . . .

But in the interests of accuracy Jerry, I believe that should be HOF (fame) points.
 
Jerry
I knew Wayne before you ever met him. I met Wayne at the Cactus Shoot way back when he came with Tony to observe only when he was a newbie, probably 1998. I loaded with Wayne and Bill Goad at The 2002 Midland Nats. The ice cream truck comment was for the 2 Harrell dies I bought. Tiime for your nap Jerry.

Stephen Perry
Angeles BR

Oh, but Stevie baby, I was there in 1948 when the first bench rested!!
 
I would like to thank guys like Jackie who have the smarts, qualifications and ability to pass on real world explanations and answers for simple questions!!!!!!

I wish there was a section on this site or any called "Questions for Jackie" or anyone else that can simply say, "This works, that don't, this is why!"

Sometimes books just don't convey all the information

Thanks,
Tony
 
Proper FL sizing die

My 6 PPC chamber was reamed with a friend's reamer----unknown, to me, dimensions.

Fired cases from this chamber were sent to Lynwood Harrell and after some discussion, I asked for the die to be .0015" smaller than the fired case.

So far, I have no complaints with this setup.

Is this not one of the accepted ways of matching the die to the chamber and, indirectly, to the reamer ?

Thanks.

A. Weldy
 
Butch

Stephen,
Butch is a very good old time shooter from the Gulf Coast. Of course now he is a half blind, snaggletoothed, demented and contankerous old coot. He has forgotten more about benchrest then most ever learn. Unfortunately he has also forgotten how to eat with utinsels, dress himself and basic human socialization. They tried putting him in a zoo once to see which group of animals he could get along with. Only two groups fit the bill. They were the giant Madagaskar hissing cockroaches and the striped hyenas. Oh well, birds of a feather etc. Tim
 
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