303 H/S gauges

[CINDERS]

Posted by nijaninja ~ A WTB - .303 Field and Go Headspace Gauge and MLE Rear Volley Sight
Seems that its a pain to get headspace gauges in Australia.

I had a machinist mate turn up 3 brass ones all for a carton of beer I have him an empty case so he could get the taper.(They are within +- .000.5")
He made me up 3 see pic .064" - .067" - .074" don't ask about the .067" one you only need 2 .064 & .074 forget the .070 as thats what the good folk here on this site say from experience.
I always drop the mag & feed the gauge up under the extractor claw rather than putting it into the chamber and forcing the claw over the rim saves the claw & stops damaging the brass as well.

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[Brian Dick]

I used to stock excellent quality MoD spec HS gauges from Arrowmark Tool and Gauge in Australia. I still have a set on my bench, .064, .067, (Vickers MMG gauge), and .074. He might try contacting Graham over there to see if he has any left or can make some more. They were expensive in the eyes of some, (not me), and I think that's why he pretty much quit making them. There are cheap coin gauges available here in the USA but they are useless IMHO. Long story.

[nijalninja]

Hey cinders, I figured I might as well ask here before bothering any of the fitting and turning mates I have about it.

Brian, I found a few places overseas that stock them for decent prices, but it seems the shipping over here is very excessive. I don't know this Graham fellow yet, but if he has any I would be willing to at least talk to him about it if nothing shows up this side of the sea. Just that I have a few old .303's now that I really am dubious about shooting, and a set for the future really couldn't hurt since I plan on getting more.

[CINDERS]

With regards to getting more Nijal, any addition we get for our licenses here in the West we have to obtain a serviceability certificate from the fire arms dealer where the weapon is being held which would includes a H/S & bore check as if they do not do that and the thing goes up they are/could be held accountable for such a disaster depending on the circumstances of such an event so its in their best interest to do the checks correctly.
Oh! they have to charge you $50.oo for the certification which puts an additional cost + Govt charges up to $240 for the addition as without that certificate the Police Firearms branch will not license the weapon.....Yay! Go the Government (oops sorry Badger!)

[Bruce_in_Oz]

It's not just the "fitting and turning".

PROPER gauges are VERY hard so that they do not distort with use. Thus, they are usually finished on a precision surface grinder.

If you are doing production work, you should have Master gauges for your HS gauges. If, like most of us mortals, you only use them, carefully, a couple of times a year and store them correctly, YOU will expire LONG before your gauges will.

Being VERY hard is also why you treat them gently, especially by NOT dropping them on concrete workshop floors, thus causing chunks to be broken off the extractor rim.

Gauges for rimmed types have a rim or else they would be pointless. Many headspace gauges for rimless rounds have NO extractor "rim" and a reduced rear diameter section so that they do not damage the extractor and reduce the influence of extractors and (spring-loaded) ejectors.

NEVER insert ANY headspace gauge in the chamber and then slam the bolt shut; you will probably damage your extractor, for a start. Slide it up under the extractor and close the bolt GENTLY and FEEL the resistance of bolt handle closure. Lee Enfield (and M-17 / P-14) actions have HELICAL locking and this can exercise a lot of force during the closure of the bolt. No more than gentle finger pressure is required. This applies to semi / full autos as well. Open-bolt SMGs are in a world of their own.

Best practice is to remove the extractor before gauging to eliminate any extraneous forces from the process.

[Sunray]

"...get the taper..." That doesn't matter. It's the thickness of the rim that matters. An original one is just the rim with enough "case body" to hold onto. No taper involved.
Like Bruce_in_Oz says, headspace gauges are precision instruments.
"...headspace gauges for rimless rounds have NO extractor "rim"..." None that I've ever seen. They always have an extractor groove.
"...pain to get headspace gauges in Australia..." That because your government doesn't want you to have 'em?

[Brian Dick]

Look up Arrowmark Tool and Gauge Pty Limited in Queensland like I said. Tell Graham I sent you and if he has a spare set, I'm sure he'll fix you up. The reason he stopped marketing them and his other precision Lee Enfield tools is because potential buyers were too cheap to pay the prices. I imported and sold his tools to serious folks for several years including milspec bolt disassembly tools and others, all superb and worth the price. I wish the HS manufacturers, (Clymer and Forster), here in the USA would make them to MoD specification but they won't. I went through the same thing with Sierra bullets trying to get them to produce a .311 diameter .303 projectile that's a Mk.7 equivalent for reloading. They are missing the boat IMHO because the SMK won't perform in original rifles that have above average service use with cordite, (all discussed at length here before). There is a market for these items and the projectiles and it will only increase as the popularity of these old rifles continues to increase and the ammo they are designed for dries up.

[nijalninja]

Cinders, you do have to love how they clamp down on gun laws so much more than smoking and alcohol which cause so many more deaths.

Bruce, I was not aware the gauges were so rigid and prone to being damaged. With this info I might save myself some money of replacing a set hopefully cheers.

Sunray, you would be correct in saying that. If they can bother you about anything gun related they will. Very discouraging to new shooters.

Brian, awesome, thank you very much for the contact, and in regards to quality and how they last I will hopefully keep this as long as I live, so price isn't too much of a big deal. Thank you very much.

[Brian Dick]

Good luck. Hopefully he can help out. I feel the same way about precision tools and gauges. They will last a lifetime + with proper care.

[Bruce_in_Oz]

Regarding "service" gauges for rimless types:

In the "good old days", many "rimless" HS gauged had partial "extractor rims". Often a section was ground away so that the spring-loaded ejector was not in play.

Most of the 5.56 and 7.62 "issue" ones I have seen in the last decade or two have only partial rims or more so in recent years, NO rim. They are generally slightly undersized in body diameter so that the just fall out of any decent chamber. The are only measuring from the face of the bolt to the chamber shoulder, anyway.

Then there are the HS and "timing" gauges for the Browning machine guns. The adoption of the "Quick Change Barrel" on the Big Fifty model has brought about more changed on the last decade or so.