Has anybody used the Stoney Point O.A.L. Gauge, for "regulating the amount of bullet clearance between the bullet's ogive and the rifling" (not my words...)?

I'm wondering if this is just another ~$40 gadget to try my patience, or of value in determining where to seat the bullet. Perhaps for precision shooters (?), but what about hunting loads (specifically .416 RM)?

Thanks!

The Stoney Point gauge is the most accurate, "repeatable" method for gaging distance to the lands. Because it is repeatable, it is also very good for monitoring throat erosion over time.

If you are into accuracy, it is invaluable and very inexpensive considering what is can do for you.

Now, for big bores, the gauge is of little value for precision seating. Most big bores require you to seat on the cannelure so you have little option in seating depth. I only use the gauge up to and including .338s. For everything over this, I seat on the cannelure.

[ 12-28-2002, 20:53: Message edited by: Zero Drift ]

I just got one for xmas and the comparators to attach to calipers. Do not have much experience yet but what I have seen the consistency of the measurements is very good. I could not reach the lands on a 270 with 130gr nos ball tips but I guess this is not unusual.

Much information can be gained with the carefull use of this gauge. Without an accurate gauge (and the comparator) it is difficult, if not impossible, to tell the difference between an OAL that is just off, just on or crushed into the rifling. For precision shooting of all kinds, this diminision often makes a BIG difference.
When using the OAL gauge and measuring for a new bullet, I take 12 consecutive measurements. I toss out the highest & lowest reading and average the remaining 10. It's very easy that way and helps eliminate the worst readings that are usually the result of human error. It does take awhile to get a good feel for the use of this gauge.
When I have a new rifle to check, I use the OAL gauge to check every bullet that I may eventually try while developing loads. IMO the bullet comparator that attaches to the caliper is a MUST.
As ZERO said, it is also a good tool for monitoring throat erosion and altering your ammo to suit the change in throat dimiensions.
VH

Great set of tools! Make sure that you buy both gauges. One of the gauges is to measure from the base of the case to the rifle's lands, while the other is used to measure the case.

Varmint Hunter gave you great intructions on how to use the Stoney Point gauges. When measuring the distance form the base of the bullet to the lands, repeat the procedure 10 or 12 times and average out the margin numbers. After you have used the gauges long enough, it will become very easy to double check your rifle. Also, after you "tap" the rod with your finger so that the bullet contacts the lands, the next step it to lock the rod with the thumb screw. When you tighten the thumb screw, make sure you don't bend the rod. If you push and bend the rod in any direction, the measurement won't be correct.

I have found that I get different readings with the case supplied by stony point (7mm mag)other than with a case that was fired in my gun and drilled and tapped to accept the O.A.L tool.

Hutt - that is becuase your case was fire formed to your exact chamber deminsions. It is always a good idea to send two fired cases to Stoney Point so that they can thread them OR you can do it yourself.

[ 12-29-2002, 05:35: Message edited by: Zero Drift ]

Hutt, the difference between the stony point case and yours is the factory case has min headspace to fit all chambers, while your fire formed case conforms to only your chamber. The difference shouldn`t be but a couple thousanths and doesn`t matter much as it`s meant to only be a repetible starting point. Your final seating depth will be measured on a loaded round anyway.
I will admit useing your own case will give a more accurate reading for your rifle.

Great product, personally I just measure 3 different bullets -- normally 2 of them come out exactly the same and I go with that measurement.

John

Thanks guys for the info and relating your personal experiences. For the .416, I'll see what kind of results I get with the North Forks seating them on the cannelure per ZD's post. When I reload my .300WM again, I think I'll give the Stony Point gauge a try.

Thanks again,
Bill

Don't like mine, would sell cheap. Use my old varmint hunter friends method.

Bill in Pa,
One other thing about seting to cannelure:- with the Lee Factory Crimp Die, cannelure location is not important....you can crimp a non-cannelured bullet. Just not sure if Lee makes the FC die for .416's.

ShondorP

Hot core: You describe miking the overall length of the set seater die.You must have the seater die locknut locked in a never move position to do this-yes?.As I see it unless this is the case both the depth of die mounting in the press as well as the seater screw adjustment affect the COL.Am I missing something?

uper, most lock their seating die just a hair off crimping the case and leave it. You`re right reseating the die in the press will change the depth of the seater.
I saw a post by Hot Core useing the die OAL as a seating depth guide a while back, tried it, and I`ve found it works great. It`s one of those things that is so obvious that you never think to try it.

I love the Stoney Point. But one thing not said here is the gun must be clean. The grit in the barrel can throw off the measurement.
Have fun

Hcliff

[ 01-06-2003, 22:07: Message edited by: Hcliff ]

Hot Core
I'm not a veteran to reloading and have a some questions about using the cleaning rod to measure land depth.
Is the rod inserted from the chamber end to the base of the bullet? What or how do you determine the measuring/reference point on the cleaning rod? Do you measure the chamber with a casing inserted and measure across bullet reference and casing reference?

[ 12-30-2002, 21:54: Message edited by: Quarter Round ]

The problem with the cleaning rod method is that there is a variance in the distance from the tip of the bullet to the ogive where it contacts the lands. If you do it that way you will have consistent variances based on those differences. It happens the same way even using the Stoney Point gauge to set your die. While the OAL of the cartridge may be the same, the distance from tip of the bullet to the base of the ogive will vary. The only thing you can do for consistency is to seat your bullets a bit long, about .007" or .008" which is the most I've seen in good bullet variance, then measure, turn down your die each time to get the distance from head of the case to the ogive identical each time. Any OAL measurement by whichever way you choose to take it, will still give you variances based on the variances of the bullets. To get absolute consistency the Stoney Point together with any kind of micrometer seating die will be the only way to do it reasonably quickly. You can do it also with a comparator such as sold by Sinclair, or by using the RCBS Precision Mics, but they are much more cumbersome and slow.

I'm sold on the Stoney Point system, you just have to know how to use it.

Bob338: You made a great point about the variances in overall cartridge length one introduces when using a rod to measure the distance from the base of the bullet to the rifle's lands. The length of the exposed lead on the bullet's nose is always different from one bullet to the next, even with bullets of the same caliber and weight. So those of you who only rely on the cleaning rod or wood dowel method have to take into account this fact. The "wood dowel" measurement is a "close enough" guess, but that's all. It will give you an idea of the overall cartridge length from the bolt's face to the tip of the bullet, but it won't give you an accurate measurement from the bolt's face to the rifle's lands, because in order to do so one would have to measure from the bolt's face to the bullet's ogive.

That's one of the main reasons why I like to use the Stoney Point gages. I can measure the distance from the bolt's face to the lands with different bullets of the same caliber, since I am measuring up to each bullet's ogive. The Stoney Point gages are caliber specific. It means that if I have a set of .338 gauges, I can check the distance to the lands for all .33 bullets regardless of brand. For example, lets say that I use a Nosler Partition, then use a .338 Swift A-Frame. Since the lead protrudes from Partition's nose, this one is slightly longer than a Swift A-Frame. The lead out the nose's tip of A-Frame bullet does not protrude like Nosler's.

I have the RCBS gage, and also the Stoney Point gage-set, and favor the Stoney Point's one. It is much easier to use.

[ 12-31-2002, 04:14: Message edited by: Ray, Alaska ]

I use the dowel method because its cheap and it makes sense to me.After getting the initial "tight"dimension I set one bullet slightly long and try fit it in the rifle.A couple of moves at most will fit it very closely to the lands.I then really like hot cores method of guaging the length to be able to repeat at a future time.

Hot Core,
You are getting real close with your methed, but with tape on the rod at the muzzle, I don't see how you could get the same level of accuracy as you can with the Stoney Point that even alows you to monitor throat erosion to the .001"?

I can see maybe .010" resolution or close but not enough for the super nit-picker.

I have the angled SP oal gauge and a comparetor as well. The SP unit will give me an accurate oal in 2 or 3 checks and all read within .001", am I lucky, I might be by the sound of it.

I split the sized neck on a case with a dremel tool and cutoff wheel on each rifle for a comparison.

I found if you squeeze the mouth a bit and insert a bullet leaving it long, insert and close bolt then remove without pulling out the bullet, it is JUST as consistant as the SP is. Do it a couple times to verify the bullet didn't pull and squeeze neck a little harder if it does. Be consistant with the tension you put on the bullet and it will work very well and not pull out.

I use this same bullet to load a dummy round to the EXACT same oal measured with the SP comparetor to set up my die and as a reference at a later time if needed. I do the same thing with another bullet of the same type, but save the SAME bullet for measuring throat erosion later on. I wright the oal on THAT bullet in permanent marker for the tests later. You have to use the same EXACT bullet later for meaningfull results.

Thought I'd post the split case method for those that aren't having luck with thir SP oal gauges or other that don't want to spend the cash on one. I did notice the split case method gave oal measurements exactly .010" longer that the SP did, must be more pressure put on the bullet than with the SP gauge. Both are absolutely consistant though.

A side note, Barnes XLC will not stay in the case when removed from the chamber on the split case method, they fit tighter in the throat and are slicker in the case mouth so good luck with them...

Hot Core,

While your method may get close there seems to be be many variables if you are trying to load .0010 off of the lands. The Stony Brook, if done properly, eliminates many other variables that you have articulated in your approach. If a person had measured the modified Stony Brook case and may be appropriate adjustments for variations (which are minimal for any reloader) then I believe this method would have a lower tolerance than yours. I do not work for Stony Brook, just an average guy trying to reduce variables.

Howdy Hot Core,

Let me give an example for the new folks following the Thread. Lets say I followed the process I mentioned above and found the Overall Die Length(ODL) to be 3.800" for the Test Bullet to Kiss-the-Lands.

Then I Seat a few at 3.800" ODL with varying amounts of powder(aka developing the Load) and shoot the targets using the Audette method while watching for all the Pressure Signs.

I find the "harmonic" is 1.5gr below the SAFE MAX load. Then I go reload a Series at that 1.5gr below SAFE MAX Load and vary the Seating Depth. Lets say the ODLs are 3.790", 3.780", 3.770", etc. on those Fine Tuning loads. In this example the best Harmonic turned out to be located with the Bullets Seated with a 3.770" ODL.

Here is where it "dawned on me" that whether or not it is REALLY 0.030" Off-the-Lands or not doesn't matter at all. What does matter is that I can duplicate that exact same 3.770" ODL for that box of bullets. And since the 3.770" ODL provided the best group(s), that's what I'm really interested in being able to repeat.

So, if my original measurements "were off" by 0.001" or even 0.010"(which is really pushing it), it would still be compensated for with the Fine Tuning Loads I shoot.

I agree completely. I also use that load development method as well.

The split neck method, I found that on here a while back somewhere and was actually on my way out to get a SP oal gauge at the time and tried it before I left just to compare the two. Glad I checked it too. It was the best method I've found using a case and bullet to get the length yet. It worked so perfectly to grip the bullet consistantly and hard enough I can finally stop looking now.

I actually use it more because it's faster than the SP, unless I'm checking the XLC bullets.

You explain yourself well, I look for the stuff I don't already know about in posts and realize the over explaining for some just helps to minimize the back and forth Q&A with others that might be left unsure. Take care.