N-133 and 6PPC case capacity.......

R

ray in seattle

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Trying to move ahead from 28.0 gr N-133 in a reformed 220 Russian Lapua case, but powder column is into the neck even at 28.3 grains and I don't think I should be shooting a compressed load....where do these 28.5gr. up to 29.0 gr. loads of N-133 come from? r in s.
 
n133 and 6ppc case capacity

long drop tubes and pour very slowly.
Be care full though lots very .
 
Ray

You say, "where do the 28.5 and 29.0 grn loads come from". Without going into any detail, most of us consider that a "mid range load".
The fact is, 133 is actually a tad slow for the 6PPC. But, many Benchrest Shooters have discovered that if you are willing to shoot it at a pressure that is a little higher than what is normally accepted, the stuff really comes to life, agging wise.
133 also has a reputation in being VERY difficult to keep tuned. When it is in tune, nothing will beat it. But, if it goes, it seems to go all the way. This is the source of aggravation for many shooters.
Once again, there are many shooters who have learned the weird quirks of this powder, and do pretty good most of the time.
It is sort of difficult for experienced Benchrest Shooters to advise a novice on how we shoot 133. As you get more into this, you will understand what I am talking about. So, to answer your question now, all you need is a drop tube that is at least 8 inches long, and operated with a very slow trickle, in order to get 29+ grns in a 6PPC case.
Don't dread compressed loads. 90 percent of extreme accuracy shooters are probably shooting compressed loads.......jackie
 
Course Lot of 133 vs. Drop Tube Differences

Ray,
What is your lot # of 133? I have been shooting 133 since its introduction to the U.S., and I have NEVER seen a lot that was course enough to create a compressed load @ 28.3g.! Are you sure that you're using a drop tube with a hole that is small enough? The hole in your drop tube should be no larger in diameter than 1/8" - 3/16". If it is, that drop tube is intended for larger, courser grained powder. With a relatively short (3") drop tube in my Lyman/Culver conversion measure, I can get 29.0-29.2g. of 133 before I even get close to having a compressed load. The fix at that point is to go to a 6" tube...which gives me about another grain of powder before becoming compressed...
 
OK, I see what I am missing...........

Drop tube, drop tube, drop tube.............Sinclair just sent arbor press and Wilson dies yesterday, I am on my way...........have never fired compressed loads in anything.........thanks all, r in s.
 
Ray
Think about the compressed load thing for a moment.

If you are shooting a case with powder laying loose inside it how do you know if the powder is laying against the flash hole the same way every time. I do not know if it really matters but it is a variable I do not want. That is why I like a case completely full of powder or even compressed.
 
ray in seattle still gathering intel.........

Load Density
Load density is the determining factor in selecting powder for a particular rifle cartridge with 86% density just about ideal in most cases. Load density is the ratio between case capacity and actual powder charge. Most factory ammunition is loaded with a density of 80% - 90% of the cartridge case capacity.

1. You should never exceed 95% load density.
a. Primers need room to flame through the powder charge which gives uniform velocity and pressure.
b. Cases that are full or compressed charges of powder will accelerate barrel wear in the rifle barrels throat area.

Hey it works! Just did a copy and paste from a reloading article..r in s.
 
Ray in Seattle still gathering info.

--------------------------------------------------------------------------------
(Copied and pasted from a reloading article?)

Load Density
Load density is the determining factor in selecting powder for a particular rifle cartridge with 86% density just about ideal in most cases. Load density is the ratio between case capacity and actual powder charge. Most factory ammunition is loaded with a density of 80% - 90% of the cartridge case capacity.

1. You should never exceed 95% load density.
a. Primers need room to flame through the powder charge which gives uniform velocity and pressure.
b. Cases that are full or compressed charges of powder will accelerate barrel wear in the rifle barrels throat area.

According to those experts we are all using the wrong powder and will wear out our barrels prematurely. They also say that seating bullets into the lands may result in unsafe pressures. This advice is fine for those who want to load the equivalant of factory ammunition for factory rifles. Not much benchrest application. Jackie explains it perfectly; we are using a powder that is a tad bit slow and using enough to bring our load into tune. If you try chronographing as you adjust your load it becomes even more confusing as the velocity kind of flattens out when you get into the upper load window. When you reach this point a small change in powder charge may increase or decrease the verticle (in your group) without seeming to affect the velocity.

Scott Roeder
 
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Well, the good thing is that 133 and 68 grain bullets in a 6ppc is a VERY forgiving combination for a beginning handloader. You can literally dip a case in a cup of powder, tap a tad-bit off so as not to spill it, and seat a bullet, and shoot (provided good custom action, barrel, good gunsmithing).
 
Ray, what you must understand is a custom BR gun correctly built is a whole different animal than normal (factory) guns. Listen to what Jackie and Kent is telling you, they are a couple of the best benchrest shooters in the nation or in the world for that matter. When I first learned how to really load a 6PPC, Ed Watson told me to start with a four inch drop tube, jam the bullet, fill the case to the bottom of the bullet with VV133, then go to a six or eight inch tube and go up from there in load development. Wise words from a great shooter will always shorten the learning curve.

Hovis
 
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