Stoney Point OAL Gauge accuracy problem.

bakerboy

bakerboy

New member
Stoney Point says accuracy within a .001. No matter how careful I am doing everything the same way, I get an occasional variance up to a .01. Variances of .005 are normal. I've made as many as 50 measurements. I throw out the top and bottom 10, then average the remaining 30. This does not seem like a very good approach, and would like some suggestions on where the variability is coming from.
My method: A clean and dry chamber in a fairly new Krieger. Use of digital caliper and bullet comparitor. ( Note: My Berger bullets measure exactly the same to the .001 in the comparitor ). The test case is screwed on the gauge securely. The gauge is inserted in the same orientation with the same tension. The same amount of pressure is used to push the bullet into the lands. The same amount of tension is used to secure the locking nut.
My only (wide guess) theory at this point, would be that the ends of the push rod/wire are not square or the locking screw pushes up or down on the rod/wire.
Any similar experiences, or better results out there?
 
I have one also, kicks my butt trying to figure it out too! A friend has one he got from Sinclair and he can't seem to remember how to use it from one load to another, so I don't trust it to much either. I end up using the old fashion way of seating long and adjust till I get no marks on the bullet.
 
i made my own outa a peace of hydrolic tube and always look at 4 sets and usaly have a + - .001 using the same bulett, but some buletts can stick in the chamber slightly and pull out causing the varrance it seems to be all in the touch
 
Accumulation of tolerances. Meaning no matter how hard you try everything is not ALWAYS going to be the same.

Just a few examples: Fit of modified case to chamber, tension applied inserting modified case, straight alignment of gauge into chamber, tension used to tap bullet into lands, concentricty of bullet at the point where contacting lands, etc.

I have used the Stoney Point (now Hornady) for years and IMO it is still the best way to determine seating depth. I will check three times and with most bullets I get a variance of no more than .003 to .004. If it is more than that I do it three more times kick out the high and low and average the rest. Most rifles won't know the difference between .005 in seating depth.

Here are a few things I do to make Stoney Point work better for me: 1. Send a fired case from your rifle to S.P. (or Hornady) and have them drill and tap to fit the gauge. 2. Chamfer inside and out of modified case neck making sure it is very smooth with no burrs. 3. If using rod guide when you have finished cleaning remove it and carefully insert a patch rotating it while going in and out of the throat area only. 4. Then use a mop to throughly clean and dry the chamber.

Hope this helps. Good Luck, and good shooting.
 
i bought ragncajn's tool and it works perfect,it is consistent and accurate.i tried different ways of finding oal, but i found that his oal tool is the best way to go.
 
i just took a fired cased deprimed drilled and taped it my self took a varry thin cut off wheel in a pencle grinder and put a couple of slits in the top of the case so the bullet is held with enough tension
 
Rajn' Cajn' has a great tool that is simple, accurate, inexpensive, sturdy, and works in a variety of action types. Me likeee... /ubbthreads/images/graemlins/grinning-smiley-003.gif
 
Quote:
Rajn' Cajn' has a great tool that is simple, accurate, inexpensive, sturdy, and works in a variety of action types. Me likeee... /ubbthreads/images/graemlins/grinning-smiley-003.gif




/ubbthreads/images/graemlins/grinning-smiley-003.gif /ubbthreads/images/graemlins/grinning-smiley-003.gif /ubbthreads/images/graemlins/grinning-smiley-003.gif /ubbthreads/images/graemlins/grinning-smiley-003.gif /ubbthreads/images/graemlins/grinning-smiley-003.gif


Me too - it stays on the bench - I have never put it away.

And it is just as accurate as the expensive Stony Point spread!

/ubbthreads/images/graemlins/laugh.gif
 
I've found that with the Stoney Point, less pressure all the way around is the best...from the bullet in the lands, to the amount of pressure I place on the locking thumb screw.

Over tightening will tend to distort the whole shebang...

I also have one of Randy's tools and not sure I'm using it right and lost the instructions....and it doesn't seem that complicated... /ubbthreads/images/graemlins/smiliesmack.gif

But then again, I don't check the chambers that often as I've got the information written down in my "Bench Book" and my ammo always has a pretty good jump space..
 
I have found that the Stoney point cases need the neck sized down just a touch to get a better purchase on the bullet. A once-fired piece of brass seems like it would tighten up the tolerances a little too.
 
my home made bullet gage with a fire formed case necked and deprimed, works great for me and half the fun of reloading is using componits you have made like my powder stand and even my shell holder but thats just me.

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