stony point oal guage

[onehole]

Hi guys thought I would mention experience I have had recently when setting up and building ammo for my new 222.I normally have had no problems with using the stony point system and their modded cases but my particular modded 222 case has led me right up the garden path!!When arriving at a measurement for just touching the lands and then making up ammo to this figure on fired cases I have found I am actually loaded almost 10 thou into the lands and not a place to be to start your load testing on this particular rifle or any other for that matter and hasten to say the groups were awful!!!I only realised what was going on on close examination of an unchambered round as I could not understand why I was getting cratering at a modest load.I used a split case method to confirm what was going on and will be using this method from now on with this particular rifle.Undoubtably if I purchased another modded case it may well suit my chamber more accurately but the message is guys to be careful and I probably think the split case method or a threaded fired case from your own rifle is the only way to get it spot on.This rifle likes a true 5 thou off and am happy now but

interestingly and on suggestion from a friend of mine he suggested loading to near sammi spec for the heads I was using and against all the rules I have ever used for reloading in the past they shot really tight and was totally amazed.This rifle has a factory spec chamber and may well have something to do with this. Does yer head in,taken me nearly 300 rounds to get to know this rifle good job its not a 6.5/284 eh Varminter.cheers onehole.

[craigyboy]

sinclair make a great tool for this job, better than stoney point's, its basically a rod guide that inserts into the actio, a bar and 2 stops to fit the bar, you put a bullet head in the chamber and push the bar up to the base of the bullet and slide one of the stops on the bar upto the back of the bore guide, then take out the bullet head and chamber a empty piece of brass, then slide the bar up to the case head on the brass and slide the other stop until it touches the back of the rod guide, then measure the length of your bullet head base to tip, measure the distance between the 2 rod stops on the bar and add the length of the bullet head to that, there you have it coal from base to tip into the lands, load one empty at that size (prefferable with the bullet head you used to take the measurment in you rifle as some bullets may vary in length) and measue this with a proper tool which measures to the ogive of the bullet from the base of the case. I have probably made it sound complicated but its only a 10 minute job.

[charly hunter]

I too have had big problems with my .243 trying to get it to shoot, and I tried everything that folks sugested but to no avail So with the help of a friend and some internet work my .243 is now shooting .280 of an inch at 100 yds. Lets face it all the best snippers in the world use factor ammo albeit match rounds and there lives depend on it, so who am I to argue with it.

I am a firm beliver that a factory rifle shoots best with factory (or near) sammi spec rounds.

[Redfox]

sites gone slow again

[Redfox]

The Stoney point modded case is just a starting point to give you the bullet contact point with the rifling. It is a std case with expanded neck not a custom one to fit your rifle and chamber. having used it to find the oal where the bulet touches the rifling, you should measure head to shoulder on 2-3 fired cases from your rifle , measure sme on the std modded case and make the necessary adjustment to your touching the rifling OAL, you then have a reference for the rest of your changes which will all be with your fired cases, if your starting with sized new cases, you will have to make the same measurement and allowance as before to get the correct OAL.

It is by far the most accurate way to do it, even having to measure the cases, which to get minimum set back with full length sizing is necessary anyway, or only needs doing the once if neck sizing.

You are effectively making engineering measurements, which is a new skill for most people and needs learning and practicing to get good results, but gets you that bit tighter group when you get it right.

Redfox

[millpool]

your sor right charly hunter ,sammi length in my.223 sub half inch 5 rnds!!!! how much more do you need ,its a box standard cz 223 with the varmint barrel ,i just dont think you can expect more from an "of the shelf" varmit rifle, onehole you will have to go the way of the "sammi e riy " get it!!!!! p.s read your personal e mail!!!!!!!!

[Andrew]

I wonder what the fuss is about these OAL gages that are being sold so dearly. The measurement obtained is, after all, just a starting point. In many cases it just gives a snap-shot of what the throating is like. It's seldom an accuracy tool in of itself.

 

For many years I have made my own OAL gages from 1/2" square extruded aluminum bar stock. I cut 2" lengths, stack them in the drill press and cross drill one end with a hole just larger then my cleaning rod. I then drill that end for a set screw to lock the halves on the rod.

 

In use, I slip both halves onto my rod and screw on a flat ended jag. I close the bolt on an empty chamber, run the rod into the bore until the jag contacts the bolt face. While holding it in place I run the halves of the gage up against the muzzle and tighten the set screw on the most distal half.

 

I remove the rod and the bolt and drop the bullet (head) of choice nose first into the empty chamber. I then nudge it up against the lands. I reinsert the rod until it touches the bullet nose and move the free half of the gage up until it touches the muzzle, tightening the set screw. The distance between the halves is the maximum allowable OAL for that bullet. I load a dummy round, take the OAL measurement from that, and record it. I then tweak the load, seating the bullet deeper until max accuracy is achieved. Best accuracy at SAAMI spec? Wouldn't surprise me!

 

This gage is simple and as sophisticated/crude as your craftsmanship will allow, but it works and is universal: No special cartridges needed. Hope some of you can make use of the idea.

 

Good shooting.~Andrew

[silentsoulsleave308holes]

what cal?????? and what bullet???? I will avva look

[silentsoulsleave308holes]

OK cheers.

 

Cal .243, Hornady 75gn V-Max

 

Cal .270, Sierra 130gn Gameking

 

 

sorry for the delay I forgot

 

.243 saami max 2.650 or bullet specific 75 gr v-max is col 2.640

 

.270 130 gameking 3.280