Do I have a Go - NO GO Issue ?

[wlleven]

I am interested in who the manufacturer is. If it is DK from PTG I am shocked that both gauges are incorrect.

stangfish,

I greatly respect your interest in whose gauges these are, but as a manufacturer myself and having done aerospace parts in the past, I know how sometimes something gets by, no matter how tight your QC may be.

My goal in this is just to have them check it, if wrong they will fix it, if the gauge is in spec then there is another issue. Being the new Hornady ammo and the Lapua brass fit and the GO gauge had issues, that raises questions.

I have been wrong before, so we will see.

wll

[handirifle]

Well not its imossible, not probable, but sure does sound suspicious. Good luck on this thing.

[earl39]

I am still wondering if you pulled the barrel and measured the protrusion like sharpshooter suggested but would like to know what the manufacturer says about the gauges.

[wlleven]

Gauges, two rounds of Hornady ammo and three Lapua brass sent off 2nd day air to the manufacturer, along with a nice letter.

wll

[ralphob]

I just read all of this thread and got really nervous that maybe something could be wrong with the headspace on my 6.5 grendel as I simply relied on my PTG go gauge to headspace it. I have no signs of trouble but this thread got me worried and I have had several problems with the bolt heads PTG has sent me. Since I have two more 6.5 grendel barrels I put my go gauge in both of them and checked the protrusion as Sharpshooter recommended. My go gauge was right on a .125 protrusion on both barrels so I am going to assume my gauge is correct and not pull the barrel off the one I built to check it.

[wlleven]

I just read all of this thread and got really nervous that maybe something could be wrong with the headspace on my 6.5 grendel as I simply relied on my PTG go gauge to headspace it. I have no signs of trouble but this thread got me worried and I have had several problems with the bolt heads PTG has sent me. Since I have two more 6.5 grendel barrels I put my go gauge in both of them and checked the protrusion as Sharpshooter recommended. My go gauge was right on a .125 protrusion on both barrels so I am going to assume my gauge is correct and not pull the barrel off the one I built to check it.

It maybe my setup is different. being this was my first build I did not want to take anything for granted. Like I mentioned I head spaced off the Lapua case and everything is fine. You can see my 3 shot test group on another thread. It is only at 50 yds but .185 ctc I can live with ;- )

I mentioned that I spent a lot of time talking to the old bench rest guys, who seem to spend their lives removing and putting on barrels .... they tend to head space carefully on a case, as it is going to be used just for that gun and chamber.

I would imagine I will hear back from the gauge manufacturer this upcoming Monday or Tuesday.


wll

[FW Conch]

ralphob, don't create any paronia in your shooting life because of reading this thread. If your cases don't chamber, you don't have enough head space. If your cases chamber, with .002" to .004" clearance, your headspace is perfect. Then take all of the cases you have and cycle them through your action, and your double perfect. It doesn't matter if you set the headspace with a go gauge, a fired casing, a new casing, or by "guess work"(not recommend) as long as the mentioned tolerance is achieved. Headspace is a big deal in rifles with shouldered barrels. The barrel nut took 99% of that big deal away. The perfect headspace,IMHO, is "zero". The headspace in all of my chambers, and casings is zero because all of my casings are "fire formed" to the chamber. Everyone out here who has ever fired Factory Loads, has probably touched off a round with "too much" head space, because they are manufactured to SAMMI specks, and some of them end up way on the low end of the tolerance. That's why it's called a "tolerance". The system can "tolerate" a "little" "too much".

This site needs a FAQ, or a "stickie" devoted to Headspace to take away the confusion.....JMHO ;-)......Jim

[earl39]

I know it is the holiday season but has there been any word back from the gauge manufacturer yet? Inquiring minds want to know.

[jonbearman]

Out of curiosity,did you by chance size your brass? If you did,could you have pushed the shoulder too far back which is a common mistake if you really dont know how to set your die.I did it once and induced a headspace issue.

[1.618]

Interested to hear the outcome on this. I would be astonished if it turned out to be the headspace gages were wrong. Seems like that's a major, major lawsuit just waiting to happen when somebody gets an eyeball full of hot gas!

[wlleven]

Interested to hear the outcome on this. I would be astonished if it turned out to be the headspace gages were wrong. Seems like that's a major, major lawsuit just waiting to happen when somebody gets an eyeball full of hot gas!

Will call the manufacturer of the head space gauge when I get back to work next week.

In the meantime, after head spacing on the Lapua new brass, the gun shoots lights out, I'm very pleased, will shoot it again tomorrow.


wll

[earl39]

jon my understanding is he used virgin brass and factory ammo to set headspace which when I checked my new lapua grendel brass would cause my gauges to appear out of spec but when measuring the protrusion from the chamber they (the gauges) measure correctly. When measuring the protrusion of new brass it is anywhere from 2-7 thousandths off depending on the piece of brass. I for one will be highly surprised if the go gauge is wrong. While i am going to assume he now has a headspace that is tighter than sammi spec the only real downfall will be the lack of reaching the full potential of the cartridge due to the powder capacity being reduced by the overly tight headspace. All that said i still want to know if (A) he checked the gauge protrusion from the chamber and (B) what the manufacturer said about the returned gauges.

[wlleven]

Well heard back from the gauge manufacturer and their gauges were on spec within .0002 ..... very precise.

What was not on spec was the Lapua brass, being .006 undersized and the Hornady being .002 undersized.

The hornady is fine but the lapua is a little to short. My head spacing using the Lapua brass and very lightly touching was the correct thing to do the manufacturer of the gauge and I agreed. I told him I like to keep both my eyes and all my fingers, and he feels the same ;- )

Just an update.


wll

[earl39]

Well now we know. Thanks for the update Wil