Head space guages needed

[SIRUS]

Does anyone know where I can find head space guages for 7.62x54R and 7.5x55 swiss? Thanks. I think with the 7.62x54R guages you have to take the extractor off the bolt to use the headspace guage...so I think the difficulty in using them makes them hard to find.

[Sniper]

I found some at gunbroker.com (http://www.gunbroker.com). Do a search for headspace and see what comes up. If I remember right, there is a user called "YankEng" who has a "coin set" of guages that don't require you to disassemble the bolt.



:sniper:

[2rangers]

Originally posted by Sniper@Feb 8 2005, 06:02 PM
I found some at gunbroker.com (http://www.gunbroker.com). Do a search for headspace and see what comes up. If I remember right, there is a user called "YankEng"* who has a "coin set" of guages that don't require you to disassemble the bolt.



:sniper:
Sniper-
You are absolutey correct on those coin-style gauges. :beer: However, I have a way to measure headspace on a RIMMED cart like 7.62x54mm and .303 brit., and the price is right. :beer: :beer: Chamber a fired case, pref. the same brand that you are using. Using a small strip of lead solder or something called "plastigauge", Put this across the head of the case.(helps to hold the muzzle down). Arrange the solder/plastigauge so that it isn't engaged by the extractor. Now close and lock the bolt. The thin solder/plastigauge will 'squish' and allow the bolt to close into battery. Carefully unlock/open the bolt, and remove the case. Gently scrape the gauging material off the case head. Using a micrometer or dial caliper, measure the thickness of the material- W/O SQUISHING IT ANYMORE. Measure the rim thickness of your case. Add the two together, and there's your headspace measurement.
EXAMPLE: thickness of mat-.003'. Thickness of case rim-.062'
Total headspace= .065'
NOTE: using this method requires somewhat of a gentle touch w/ a mic or dial caliper, but is generally accurate. Make sure you are measuring the part squished between the bolt head and the rim. Don't measure the portion that is on the primer, and any lettering stamped in the head. Find a place where it is nice and smooth, w/ solid 'bolt-to-case head' contact.
Just thought I'd give some low-buck tips for any that are interested.
:sniper:

[Sniper]

All tips and tricks are welcomed. I think I paid $45 for a complete set about 5 or 6 years ago. Don't know what they're going for now.



:sniper:

[Tailgunner]

If you using real "plastigauge" it comes with a width=thickness gauge on the wrapper.
You can also add layers of "scotch tape" to the back of the rim and count the layers.
Unless your doing chambering work, all you need is a NO-GO gauge (if a factory load will chamber and the NO-GO won't your within spec).
With any HS gauge you need to remove the extractor, ejector and firing pin from the bolt.

[Sniper]

In case you haven't seen the "coin-style" of guages I'll dig them out and post a pic of them. No need to take the bolt apart, just open the bolt, put them in and closed the bolt gently.

:sniper:

[Sniper]

Here's a picture of the "coin-style" guages. They're marked with a small notch in the cutout section.

1 notch - "GO"
2 notch - "NO-GO"
3 notch - "FIELD" or as I call it, throw it in the field. :lol:


:sniper:

[mikr]

yankee engineering (http://hometown.aol.com/__121b_7SbxBWYj0zwTxei+Fv6F21MIfDJVbzNcLSkMkB82J9g IsBHMzdsVtg==)

I used those exact gages after swapping out a bolt head with extractor (do not remove extractors unless they are broken--to easy to permanently ruin one)---works great!!!!!

[mikr]

Originally posted by Sniper@Feb 10 2005, 04:00 PM
3 notch - "FIELD" or as I call it, throw it in the field.
With Field it will still be serviceable--one might want to try swapping out bolt heads with extractors to get a forced match closer to the NO GO specs. But all is not lost at all if it won't close on a field.

[kwg020]

Brownell's has the 7.62 x 54R but I did not see the 7.5 by 55 in their last catalog. With Brownell's you can special order some other calibers. You might get lucky if you give them a call.

[mikr]

The brownell's gages being offered requires removal of the extractor, something that you want to avoid doing at all costs if possible.